diff options
Diffstat (limited to 'fs/ext3/inode.c')
| -rw-r--r-- | fs/ext3/inode.c | 3574 |
1 files changed, 0 insertions, 3574 deletions
diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c deleted file mode 100644 index 6c7e5468a..000000000 --- a/fs/ext3/inode.c +++ /dev/null @@ -1,3574 +0,0 @@ -/* - * linux/fs/ext3/inode.c - * - * Copyright (C) 1992, 1993, 1994, 1995 - * Remy Card (card@masi.ibp.fr) - * Laboratoire MASI - Institut Blaise Pascal - * Universite Pierre et Marie Curie (Paris VI) - * - * from - * - * linux/fs/minix/inode.c - * - * Copyright (C) 1991, 1992 Linus Torvalds - * - * Goal-directed block allocation by Stephen Tweedie - * (sct@redhat.com), 1993, 1998 - * Big-endian to little-endian byte-swapping/bitmaps by - * David S. Miller (davem@caip.rutgers.edu), 1995 - * 64-bit file support on 64-bit platforms by Jakub Jelinek - * (jj@sunsite.ms.mff.cuni.cz) - * - * Assorted race fixes, rewrite of ext3_get_block() by Al Viro, 2000 - */ - -#include <linux/highuid.h> -#include <linux/quotaops.h> -#include <linux/writeback.h> -#include <linux/mpage.h> -#include <linux/namei.h> -#include <linux/uio.h> -#include "ext3.h" -#include "xattr.h" -#include "acl.h" - -static int ext3_writepage_trans_blocks(struct inode *inode); -static int ext3_block_truncate_page(struct inode *inode, loff_t from); - -/* - * Test whether an inode is a fast symlink. - */ -static int ext3_inode_is_fast_symlink(struct inode *inode) -{ - int ea_blocks = EXT3_I(inode)->i_file_acl ? - (inode->i_sb->s_blocksize >> 9) : 0; - - return (S_ISLNK(inode->i_mode) && inode->i_blocks - ea_blocks == 0); -} - -/* - * The ext3 forget function must perform a revoke if we are freeing data - * which has been journaled. Metadata (eg. indirect blocks) must be - * revoked in all cases. - * - * "bh" may be NULL: a metadata block may have been freed from memory - * but there may still be a record of it in the journal, and that record - * still needs to be revoked. - */ -int ext3_forget(handle_t *handle, int is_metadata, struct inode *inode, - struct buffer_head *bh, ext3_fsblk_t blocknr) -{ - int err; - - might_sleep(); - - trace_ext3_forget(inode, is_metadata, blocknr); - BUFFER_TRACE(bh, "enter"); - - jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, " - "data mode %lx\n", - bh, is_metadata, inode->i_mode, - test_opt(inode->i_sb, DATA_FLAGS)); - - /* Never use the revoke function if we are doing full data - * journaling: there is no need to, and a V1 superblock won't - * support it. Otherwise, only skip the revoke on un-journaled - * data blocks. */ - - if (test_opt(inode->i_sb, DATA_FLAGS) == EXT3_MOUNT_JOURNAL_DATA || - (!is_metadata && !ext3_should_journal_data(inode))) { - if (bh) { - BUFFER_TRACE(bh, "call journal_forget"); - return ext3_journal_forget(handle, bh); - } - return 0; - } - - /* - * data!=journal && (is_metadata || should_journal_data(inode)) - */ - BUFFER_TRACE(bh, "call ext3_journal_revoke"); - err = ext3_journal_revoke(handle, blocknr, bh); - if (err) - ext3_abort(inode->i_sb, __func__, - "error %d when attempting revoke", err); - BUFFER_TRACE(bh, "exit"); - return err; -} - -/* - * Work out how many blocks we need to proceed with the next chunk of a - * truncate transaction. - */ -static unsigned long blocks_for_truncate(struct inode *inode) -{ - unsigned long needed; - - needed = inode->i_blocks >> (inode->i_sb->s_blocksize_bits - 9); - - /* Give ourselves just enough room to cope with inodes in which - * i_blocks is corrupt: we've seen disk corruptions in the past - * which resulted in random data in an inode which looked enough - * like a regular file for ext3 to try to delete it. Things - * will go a bit crazy if that happens, but at least we should - * try not to panic the whole kernel. */ - if (needed < 2) - needed = 2; - - /* But we need to bound the transaction so we don't overflow the - * journal. */ - if (needed > EXT3_MAX_TRANS_DATA) - needed = EXT3_MAX_TRANS_DATA; - - return EXT3_DATA_TRANS_BLOCKS(inode->i_sb) + needed; -} - -/* - * Truncate transactions can be complex and absolutely huge. So we need to - * be able to restart the transaction at a conventient checkpoint to make - * sure we don't overflow the journal. - * - * start_transaction gets us a new handle for a truncate transaction, - * and extend_transaction tries to extend the existing one a bit. If - * extend fails, we need to propagate the failure up and restart the - * transaction in the top-level truncate loop. --sct - */ -static handle_t *start_transaction(struct inode *inode) -{ - handle_t *result; - - result = ext3_journal_start(inode, blocks_for_truncate(inode)); - if (!IS_ERR(result)) - return result; - - ext3_std_error(inode->i_sb, PTR_ERR(result)); - return result; -} - -/* - * Try to extend this transaction for the purposes of truncation. - * - * Returns 0 if we managed to create more room. If we can't create more - * room, and the transaction must be restarted we return 1. - */ -static int try_to_extend_transaction(handle_t *handle, struct inode *inode) -{ - if (handle->h_buffer_credits > EXT3_RESERVE_TRANS_BLOCKS) - return 0; - if (!ext3_journal_extend(handle, blocks_for_truncate(inode))) - return 0; - return 1; -} - -/* - * Restart the transaction associated with *handle. This does a commit, - * so before we call here everything must be consistently dirtied against - * this transaction. - */ -static int truncate_restart_transaction(handle_t *handle, struct inode *inode) -{ - int ret; - - jbd_debug(2, "restarting handle %p\n", handle); - /* - * Drop truncate_mutex to avoid deadlock with ext3_get_blocks_handle - * At this moment, get_block can be called only for blocks inside - * i_size since page cache has been already dropped and writes are - * blocked by i_mutex. So we can safely drop the truncate_mutex. - */ - mutex_unlock(&EXT3_I(inode)->truncate_mutex); - ret = ext3_journal_restart(handle, blocks_for_truncate(inode)); - mutex_lock(&EXT3_I(inode)->truncate_mutex); - return ret; -} - -/* - * Called at inode eviction from icache - */ -void ext3_evict_inode (struct inode *inode) -{ - struct ext3_inode_info *ei = EXT3_I(inode); - struct ext3_block_alloc_info *rsv; - handle_t *handle; - int want_delete = 0; - - trace_ext3_evict_inode(inode); - if (!inode->i_nlink && !is_bad_inode(inode)) { - dquot_initialize(inode); - want_delete = 1; - } - - /* - * When journalling data dirty buffers are tracked only in the journal. - * So although mm thinks everything is clean and ready for reaping the - * inode might still have some pages to write in the running - * transaction or waiting to be checkpointed. Thus calling - * journal_invalidatepage() (via truncate_inode_pages()) to discard - * these buffers can cause data loss. Also even if we did not discard - * these buffers, we would have no way to find them after the inode - * is reaped and thus user could see stale data if he tries to read - * them before the transaction is checkpointed. So be careful and - * force everything to disk here... We use ei->i_datasync_tid to - * store the newest transaction containing inode's data. - * - * Note that directories do not have this problem because they don't - * use page cache. - * - * The s_journal check handles the case when ext3_get_journal() fails - * and puts the journal inode. - */ - if (inode->i_nlink && ext3_should_journal_data(inode) && - EXT3_SB(inode->i_sb)->s_journal && - (S_ISLNK(inode->i_mode) || S_ISREG(inode->i_mode)) && - inode->i_ino != EXT3_JOURNAL_INO) { - tid_t commit_tid = atomic_read(&ei->i_datasync_tid); - journal_t *journal = EXT3_SB(inode->i_sb)->s_journal; - - log_start_commit(journal, commit_tid); - log_wait_commit(journal, commit_tid); - filemap_write_and_wait(&inode->i_data); - } - truncate_inode_pages_final(&inode->i_data); - - ext3_discard_reservation(inode); - rsv = ei->i_block_alloc_info; - ei->i_block_alloc_info = NULL; - if (unlikely(rsv)) - kfree(rsv); - - if (!want_delete) - goto no_delete; - - handle = start_transaction(inode); - if (IS_ERR(handle)) { - /* - * If we're going to skip the normal cleanup, we still need to - * make sure that the in-core orphan linked list is properly - * cleaned up. - */ - ext3_orphan_del(NULL, inode); - goto no_delete; - } - - if (IS_SYNC(inode)) - handle->h_sync = 1; - inode->i_size = 0; - if (inode->i_blocks) - ext3_truncate(inode); - /* - * Kill off the orphan record created when the inode lost the last - * link. Note that ext3_orphan_del() has to be able to cope with the - * deletion of a non-existent orphan - ext3_truncate() could - * have removed the record. - */ - ext3_orphan_del(handle, inode); - ei->i_dtime = get_seconds(); - - /* - * One subtle ordering requirement: if anything has gone wrong - * (transaction abort, IO errors, whatever), then we can still - * do these next steps (the fs will already have been marked as - * having errors), but we can't free the inode if the mark_dirty - * fails. - */ - if (ext3_mark_inode_dirty(handle, inode)) { - /* If that failed, just dquot_drop() and be done with that */ - dquot_drop(inode); - clear_inode(inode); - } else { - ext3_xattr_delete_inode(handle, inode); - dquot_free_inode(inode); - dquot_drop(inode); - clear_inode(inode); - ext3_free_inode(handle, inode); - } - ext3_journal_stop(handle); - return; -no_delete: - clear_inode(inode); - dquot_drop(inode); -} - -typedef struct { - __le32 *p; - __le32 key; - struct buffer_head *bh; -} Indirect; - -static inline void add_chain(Indirect *p, struct buffer_head *bh, __le32 *v) -{ - p->key = *(p->p = v); - p->bh = bh; -} - -static int verify_chain(Indirect *from, Indirect *to) -{ - while (from <= to && from->key == *from->p) - from++; - return (from > to); -} - -/** - * ext3_block_to_path - parse the block number into array of offsets - * @inode: inode in question (we are only interested in its superblock) - * @i_block: block number to be parsed - * @offsets: array to store the offsets in - * @boundary: set this non-zero if the referred-to block is likely to be - * followed (on disk) by an indirect block. - * - * To store the locations of file's data ext3 uses a data structure common - * for UNIX filesystems - tree of pointers anchored in the inode, with - * data blocks at leaves and indirect blocks in intermediate nodes. - * This function translates the block number into path in that tree - - * return value is the path length and @offsets[n] is the offset of - * pointer to (n+1)th node in the nth one. If @block is out of range - * (negative or too large) warning is printed and zero returned. - * - * Note: function doesn't find node addresses, so no IO is needed. All - * we need to know is the capacity of indirect blocks (taken from the - * inode->i_sb). - */ - -/* - * Portability note: the last comparison (check that we fit into triple - * indirect block) is spelled differently, because otherwise on an - * architecture with 32-bit longs and 8Kb pages we might get into trouble - * if our filesystem had 8Kb blocks. We might use long long, but that would - * kill us on x86. Oh, well, at least the sign propagation does not matter - - * i_block would have to be negative in the very beginning, so we would not - * get there at all. - */ - -static int ext3_block_to_path(struct inode *inode, - long i_block, int offsets[4], int *boundary) -{ - int ptrs = EXT3_ADDR_PER_BLOCK(inode->i_sb); - int ptrs_bits = EXT3_ADDR_PER_BLOCK_BITS(inode->i_sb); - const long direct_blocks = EXT3_NDIR_BLOCKS, - indirect_blocks = ptrs, - double_blocks = (1 << (ptrs_bits * 2)); - int n = 0; - int final = 0; - - if (i_block < 0) { - ext3_warning (inode->i_sb, "ext3_block_to_path", "block < 0"); - } else if (i_block < direct_blocks) { - offsets[n++] = i_block; - final = direct_blocks; - } else if ( (i_block -= direct_blocks) < indirect_blocks) { - offsets[n++] = EXT3_IND_BLOCK; - offsets[n++] = i_block; - final = ptrs; - } else if ((i_block -= indirect_blocks) < double_blocks) { - offsets[n++] = EXT3_DIND_BLOCK; - offsets[n++] = i_block >> ptrs_bits; - offsets[n++] = i_block & (ptrs - 1); - final = ptrs; - } else if (((i_block -= double_blocks) >> (ptrs_bits * 2)) < ptrs) { - offsets[n++] = EXT3_TIND_BLOCK; - offsets[n++] = i_block >> (ptrs_bits * 2); - offsets[n++] = (i_block >> ptrs_bits) & (ptrs - 1); - offsets[n++] = i_block & (ptrs - 1); - final = ptrs; - } else { - ext3_warning(inode->i_sb, "ext3_block_to_path", "block > big"); - } - if (boundary) - *boundary = final - 1 - (i_block & (ptrs - 1)); - return n; -} - -/** - * ext3_get_branch - read the chain of indirect blocks leading to data - * @inode: inode in question - * @depth: depth of the chain (1 - direct pointer, etc.) - * @offsets: offsets of pointers in inode/indirect blocks - * @chain: place to store the result - * @err: here we store the error value - * - * Function fills the array of triples <key, p, bh> and returns %NULL - * if everything went OK or the pointer to the last filled triple - * (incomplete one) otherwise. Upon the return chain[i].key contains - * the number of (i+1)-th block in the chain (as it is stored in memory, - * i.e. little-endian 32-bit), chain[i].p contains the address of that - * number (it points into struct inode for i==0 and into the bh->b_data - * for i>0) and chain[i].bh points to the buffer_head of i-th indirect - * block for i>0 and NULL for i==0. In other words, it holds the block - * numbers of the chain, addresses they were taken from (and where we can - * verify that chain did not change) and buffer_heads hosting these - * numbers. - * - * Function stops when it stumbles upon zero pointer (absent block) - * (pointer to last triple returned, *@err == 0) - * or when it gets an IO error reading an indirect block - * (ditto, *@err == -EIO) - * or when it notices that chain had been changed while it was reading - * (ditto, *@err == -EAGAIN) - * or when it reads all @depth-1 indirect blocks successfully and finds - * the whole chain, all way to the data (returns %NULL, *err == 0). - */ -static Indirect *ext3_get_branch(struct inode *inode, int depth, int *offsets, - Indirect chain[4], int *err) -{ - struct super_block *sb = inode->i_sb; - Indirect *p = chain; - struct buffer_head *bh; - - *err = 0; - /* i_data is not going away, no lock needed */ - add_chain (chain, NULL, EXT3_I(inode)->i_data + *offsets); - if (!p->key) - goto no_block; - while (--depth) { - bh = sb_bread(sb, le32_to_cpu(p->key)); - if (!bh) - goto failure; - /* Reader: pointers */ - if (!verify_chain(chain, p)) - goto changed; - add_chain(++p, bh, (__le32*)bh->b_data + *++offsets); - /* Reader: end */ - if (!p->key) - goto no_block; - } - return NULL; - -changed: - brelse(bh); - *err = -EAGAIN; - goto no_block; -failure: - *err = -EIO; -no_block: - return p; -} - -/** - * ext3_find_near - find a place for allocation with sufficient locality - * @inode: owner - * @ind: descriptor of indirect block. - * - * This function returns the preferred place for block allocation. - * It is used when heuristic for sequential allocation fails. - * Rules are: - * + if there is a block to the left of our position - allocate near it. - * + if pointer will live in indirect block - allocate near that block. - * + if pointer will live in inode - allocate in the same - * cylinder group. - * - * In the latter case we colour the starting block by the callers PID to - * prevent it from clashing with concurrent allocations for a different inode - * in the same block group. The PID is used here so that functionally related - * files will be close-by on-disk. - * - * Caller must make sure that @ind is valid and will stay that way. - */ -static ext3_fsblk_t ext3_find_near(struct inode *inode, Indirect *ind) -{ - struct ext3_inode_info *ei = EXT3_I(inode); - __le32 *start = ind->bh ? (__le32*) ind->bh->b_data : ei->i_data; - __le32 *p; - ext3_fsblk_t bg_start; - ext3_grpblk_t colour; - - /* Try to find previous block */ - for (p = ind->p - 1; p >= start; p--) { - if (*p) - return le32_to_cpu(*p); - } - - /* No such thing, so let's try location of indirect block */ - if (ind->bh) - return ind->bh->b_blocknr; - - /* - * It is going to be referred to from the inode itself? OK, just put it - * into the same cylinder group then. - */ - bg_start = ext3_group_first_block_no(inode->i_sb, ei->i_block_group); - colour = (current->pid % 16) * - (EXT3_BLOCKS_PER_GROUP(inode->i_sb) / 16); - return bg_start + colour; -} - -/** - * ext3_find_goal - find a preferred place for allocation. - * @inode: owner - * @block: block we want - * @partial: pointer to the last triple within a chain - * - * Normally this function find the preferred place for block allocation, - * returns it. - */ - -static ext3_fsblk_t ext3_find_goal(struct inode *inode, long block, - Indirect *partial) -{ - struct ext3_block_alloc_info *block_i; - - block_i = EXT3_I(inode)->i_block_alloc_info; - - /* - * try the heuristic for sequential allocation, - * failing that at least try to get decent locality. - */ - if (block_i && (block == block_i->last_alloc_logical_block + 1) - && (block_i->last_alloc_physical_block != 0)) { - return block_i->last_alloc_physical_block + 1; - } - - return ext3_find_near(inode, partial); -} - -/** - * ext3_blks_to_allocate - Look up the block map and count the number - * of direct blocks need to be allocated for the given branch. - * - * @branch: chain of indirect blocks - * @k: number of blocks need for indirect blocks - * @blks: number of data blocks to be mapped. - * @blocks_to_boundary: the offset in the indirect block - * - * return the total number of blocks to be allocate, including the - * direct and indirect blocks. - */ -static int ext3_blks_to_allocate(Indirect *branch, int k, unsigned long blks, - int blocks_to_boundary) -{ - unsigned long count = 0; - - /* - * Simple case, [t,d]Indirect block(s) has not allocated yet - * then it's clear blocks on that path have not allocated - */ - if (k > 0) { - /* right now we don't handle cross boundary allocation */ - if (blks < blocks_to_boundary + 1) - count += blks; - else - count += blocks_to_boundary + 1; - return count; - } - - count++; - while (count < blks && count <= blocks_to_boundary && - le32_to_cpu(*(branch[0].p + count)) == 0) { - count++; - } - return count; -} - -/** - * ext3_alloc_blocks - multiple allocate blocks needed for a branch - * @handle: handle for this transaction - * @inode: owner - * @goal: preferred place for allocation - * @indirect_blks: the number of blocks need to allocate for indirect - * blocks - * @blks: number of blocks need to allocated for direct blocks - * @new_blocks: on return it will store the new block numbers for - * the indirect blocks(if needed) and the first direct block, - * @err: here we store the error value - * - * return the number of direct blocks allocated - */ -static int ext3_alloc_blocks(handle_t *handle, struct inode *inode, - ext3_fsblk_t goal, int indirect_blks, int blks, - ext3_fsblk_t new_blocks[4], int *err) -{ - int target, i; - unsigned long count = 0; - int index = 0; - ext3_fsblk_t current_block = 0; - int ret = 0; - - /* - * Here we try to allocate the requested multiple blocks at once, - * on a best-effort basis. - * To build a branch, we should allocate blocks for - * the indirect blocks(if not allocated yet), and at least - * the first direct block of this branch. That's the - * minimum number of blocks need to allocate(required) - */ - target = blks + indirect_blks; - - while (1) { - count = target; - /* allocating blocks for indirect blocks and direct blocks */ - current_block = ext3_new_blocks(handle,inode,goal,&count,err); - if (*err) - goto failed_out; - - target -= count; - /* allocate blocks for indirect blocks */ - while (index < indirect_blks && count) { - new_blocks[index++] = current_block++; - count--; - } - - if (count > 0) - break; - } - - /* save the new block number for the first direct block */ - new_blocks[index] = current_block; - - /* total number of blocks allocated for direct blocks */ - ret = count; - *err = 0; - return ret; -failed_out: - for (i = 0; i <index; i++) - ext3_free_blocks(handle, inode, new_blocks[i], 1); - return ret; -} - -/** - * ext3_alloc_branch - allocate and set up a chain of blocks. - * @handle: handle for this transaction - * @inode: owner - * @indirect_blks: number of allocated indirect blocks - * @blks: number of allocated direct blocks - * @goal: preferred place for allocation - * @offsets: offsets (in the blocks) to store the pointers to next. - * @branch: place to store the chain in. - * - * This function allocates blocks, zeroes out all but the last one, - * links them into chain and (if we are synchronous) writes them to disk. - * In other words, it prepares a branch that can be spliced onto the - * inode. It stores the information about that chain in the branch[], in - * the same format as ext3_get_branch() would do. We are calling it after - * we had read the existing part of chain and partial points to the last - * triple of that (one with zero ->key). Upon the exit we have the same - * picture as after the successful ext3_get_block(), except that in one - * place chain is disconnected - *branch->p is still zero (we did not - * set the last link), but branch->key contains the number that should - * be placed into *branch->p to fill that gap. - * - * If allocation fails we free all blocks we've allocated (and forget - * their buffer_heads) and return the error value the from failed - * ext3_alloc_block() (normally -ENOSPC). Otherwise we set the chain - * as described above and return 0. - */ -static int ext3_alloc_branch(handle_t *handle, struct inode *inode, - int indirect_blks, int *blks, ext3_fsblk_t goal, - int *offsets, Indirect *branch) -{ - int blocksize = inode->i_sb->s_blocksize; - int i, n = 0; - int err = 0; - struct buffer_head *bh; - int num; - ext3_fsblk_t new_blocks[4]; - ext3_fsblk_t current_block; - - num = ext3_alloc_blocks(handle, inode, goal, indirect_blks, - *blks, new_blocks, &err); - if (err) - return err; - - branch[0].key = cpu_to_le32(new_blocks[0]); - /* - * metadata blocks and data blocks are allocated. - */ - for (n = 1; n <= indirect_blks; n++) { - /* - * Get buffer_head for parent block, zero it out - * and set the pointer to new one, then send - * parent to disk. - */ - bh = sb_getblk(inode->i_sb, new_blocks[n-1]); - if (unlikely(!bh)) { - err = -ENOMEM; - goto failed; - } - branch[n].bh = bh; - lock_buffer(bh); - BUFFER_TRACE(bh, "call get_create_access"); - err = ext3_journal_get_create_access(handle, bh); - if (err) { - unlock_buffer(bh); - brelse(bh); - goto failed; - } - - memset(bh->b_data, 0, blocksize); - branch[n].p = (__le32 *) bh->b_data + offsets[n]; - branch[n].key = cpu_to_le32(new_blocks[n]); - *branch[n].p = branch[n].key; - if ( n == indirect_blks) { - current_block = new_blocks[n]; - /* - * End of chain, update the last new metablock of - * the chain to point to the new allocated - * data blocks numbers - */ - for (i=1; i < num; i++) - *(branch[n].p + i) = cpu_to_le32(++current_block); - } - BUFFER_TRACE(bh, "marking uptodate"); - set_buffer_uptodate(bh); - unlock_buffer(bh); - - BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); - err = ext3_journal_dirty_metadata(handle, bh); - if (err) - goto failed; - } - *blks = num; - return err; -failed: - /* Allocation failed, free what we already allocated */ - for (i = 1; i <= n ; i++) { - BUFFER_TRACE(branch[i].bh, "call journal_forget"); - ext3_journal_forget(handle, branch[i].bh); - } - for (i = 0; i < indirect_blks; i++) - ext3_free_blocks(handle, inode, new_blocks[i], 1); - - ext3_free_blocks(handle, inode, new_blocks[i], num); - - return err; -} - -/** - * ext3_splice_branch - splice the allocated branch onto inode. - * @handle: handle for this transaction - * @inode: owner - * @block: (logical) number of block we are adding - * @where: location of missing link - * @num: number of indirect blocks we are adding - * @blks: number of direct blocks we are adding - * - * This function fills the missing link and does all housekeeping needed in - * inode (->i_blocks, etc.). In case of success we end up with the full - * chain to new block and return 0. - */ -static int ext3_splice_branch(handle_t *handle, struct inode *inode, - long block, Indirect *where, int num, int blks) -{ - int i; - int err = 0; - struct ext3_block_alloc_info *block_i; - ext3_fsblk_t current_block; - struct ext3_inode_info *ei = EXT3_I(inode); - struct timespec now; - - block_i = ei->i_block_alloc_info; - /* - * If we're splicing into a [td]indirect block (as opposed to the - * inode) then we need to get write access to the [td]indirect block - * before the splice. - */ - if (where->bh) { - BUFFER_TRACE(where->bh, "get_write_access"); - err = ext3_journal_get_write_access(handle, where->bh); - if (err) - goto err_out; - } - /* That's it */ - - *where->p = where->key; - - /* - * Update the host buffer_head or inode to point to more just allocated - * direct blocks blocks - */ - if (num == 0 && blks > 1) { - current_block = le32_to_cpu(where->key) + 1; - for (i = 1; i < blks; i++) - *(where->p + i ) = cpu_to_le32(current_block++); - } - - /* - * update the most recently allocated logical & physical block - * in i_block_alloc_info, to assist find the proper goal block for next - * allocation - */ - if (block_i) { - block_i->last_alloc_logical_block = block + blks - 1; - block_i->last_alloc_physical_block = - le32_to_cpu(where[num].key) + blks - 1; - } - - /* We are done with atomic stuff, now do the rest of housekeeping */ - now = CURRENT_TIME_SEC; - if (!timespec_equal(&inode->i_ctime, &now) || !where->bh) { - inode->i_ctime = now; - ext3_mark_inode_dirty(handle, inode); - } - /* ext3_mark_inode_dirty already updated i_sync_tid */ - atomic_set(&ei->i_datasync_tid, handle->h_transaction->t_tid); - - /* had we spliced it onto indirect block? */ - if (where->bh) { - /* - * If we spliced it onto an indirect block, we haven't - * altered the inode. Note however that if it is being spliced - * onto an indirect block at the very end of the file (the - * file is growing) then we *will* alter the inode to reflect - * the new i_size. But that is not done here - it is done in - * generic_commit_write->__mark_inode_dirty->ext3_dirty_inode. - */ - jbd_debug(5, "splicing indirect only\n"); - BUFFER_TRACE(where->bh, "call ext3_journal_dirty_metadata"); - err = ext3_journal_dirty_metadata(handle, where->bh); - if (err) - goto err_out; - } else { - /* - * OK, we spliced it into the inode itself on a direct block. - * Inode was dirtied above. - */ - jbd_debug(5, "splicing direct\n"); - } - return err; - -err_out: - for (i = 1; i <= num; i++) { - BUFFER_TRACE(where[i].bh, "call journal_forget"); - ext3_journal_forget(handle, where[i].bh); - ext3_free_blocks(handle,inode,le32_to_cpu(where[i-1].key),1); - } - ext3_free_blocks(handle, inode, le32_to_cpu(where[num].key), blks); - - return err; -} - -/* - * Allocation strategy is simple: if we have to allocate something, we will - * have to go the whole way to leaf. So let's do it before attaching anything - * to tree, set linkage between the newborn blocks, write them if sync is - * required, recheck the path, free and repeat if check fails, otherwise - * set the last missing link (that will protect us from any truncate-generated - * removals - all blocks on the path are immune now) and possibly force the - * write on the parent block. - * That has a nice additional property: no special recovery from the failed - * allocations is needed - we simply release blocks and do not touch anything - * reachable from inode. - * - * `handle' can be NULL if create == 0. - * - * The BKL may not be held on entry here. Be sure to take it early. - * return > 0, # of blocks mapped or allocated. - * return = 0, if plain lookup failed. - * return < 0, error case. - */ -int ext3_get_blocks_handle(handle_t *handle, struct inode *inode, - sector_t iblock, unsigned long maxblocks, - struct buffer_head *bh_result, - int create) -{ - int err = -EIO; - int offsets[4]; - Indirect chain[4]; - Indirect *partial; - ext3_fsblk_t goal; - int indirect_blks; - int blocks_to_boundary = 0; - int depth; - struct ext3_inode_info *ei = EXT3_I(inode); - int count = 0; - ext3_fsblk_t first_block = 0; - - - trace_ext3_get_blocks_enter(inode, iblock, maxblocks, create); - J_ASSERT(handle != NULL || create == 0); - depth = ext3_block_to_path(inode,iblock,offsets,&blocks_to_boundary); - - if (depth == 0) - goto out; - - partial = ext3_get_branch(inode, depth, offsets, chain, &err); - - /* Simplest case - block found, no allocation needed */ - if (!partial) { - first_block = le32_to_cpu(chain[depth - 1].key); - clear_buffer_new(bh_result); - count++; - /*map more blocks*/ - while (count < maxblocks && count <= blocks_to_boundary) { - ext3_fsblk_t blk; - - if (!verify_chain(chain, chain + depth - 1)) { - /* - * Indirect block might be removed by - * truncate while we were reading it. - * Handling of that case: forget what we've - * got now. Flag the err as EAGAIN, so it - * will reread. - */ - err = -EAGAIN; - count = 0; - break; - } - blk = le32_to_cpu(*(chain[depth-1].p + count)); - - if (blk == first_block + count) - count++; - else - break; - } - if (err != -EAGAIN) - goto got_it; - } - - /* Next simple case - plain lookup or failed read of indirect block */ - if (!create || err == -EIO) - goto cleanup; - - /* - * Block out ext3_truncate while we alter the tree - */ - mutex_lock(&ei->truncate_mutex); - - /* - * If the indirect block is missing while we are reading - * the chain(ext3_get_branch() returns -EAGAIN err), or - * if the chain has been changed after we grab the semaphore, - * (either because another process truncated this branch, or - * another get_block allocated this branch) re-grab the chain to see if - * the request block has been allocated or not. - * - * Since we already block the truncate/other get_block - * at this point, we will have the current copy of the chain when we - * splice the branch into the tree. - */ - if (err == -EAGAIN || !verify_chain(chain, partial)) { - while (partial > chain) { - brelse(partial->bh); - partial--; - } - partial = ext3_get_branch(inode, depth, offsets, chain, &err); - if (!partial) { - count++; - mutex_unlock(&ei->truncate_mutex); - if (err) - goto cleanup; - clear_buffer_new(bh_result); - goto got_it; - } - } - - /* - * Okay, we need to do block allocation. Lazily initialize the block - * allocation info here if necessary - */ - if (S_ISREG(inode->i_mode) && (!ei->i_block_alloc_info)) - ext3_init_block_alloc_info(inode); - - goal = ext3_find_goal(inode, iblock, partial); - - /* the number of blocks need to allocate for [d,t]indirect blocks */ - indirect_blks = (chain + depth) - partial - 1; - - /* - * Next look up the indirect map to count the totoal number of - * direct blocks to allocate for this branch. - */ - count = ext3_blks_to_allocate(partial, indirect_blks, - maxblocks, blocks_to_boundary); - err = ext3_alloc_branch(handle, inode, indirect_blks, &count, goal, - offsets + (partial - chain), partial); - - /* - * The ext3_splice_branch call will free and forget any buffers - * on the new chain if there is a failure, but that risks using - * up transaction credits, especially for bitmaps where the - * credits cannot be returned. Can we handle this somehow? We - * may need to return -EAGAIN upwards in the worst case. --sct - */ - if (!err) - err = ext3_splice_branch(handle, inode, iblock, - partial, indirect_blks, count); - mutex_unlock(&ei->truncate_mutex); - if (err) - goto cleanup; - - set_buffer_new(bh_result); -got_it: - map_bh(bh_result, inode->i_sb, le32_to_cpu(chain[depth-1].key)); - if (count > blocks_to_boundary) - set_buffer_boundary(bh_result); - err = count; - /* Clean up and exit */ - partial = chain + depth - 1; /* the whole chain */ -cleanup: - while (partial > chain) { - BUFFER_TRACE(partial->bh, "call brelse"); - brelse(partial->bh); - partial--; - } - BUFFER_TRACE(bh_result, "returned"); -out: - trace_ext3_get_blocks_exit(inode, iblock, - depth ? le32_to_cpu(chain[depth-1].key) : 0, - count, err); - return err; -} - -/* Maximum number of blocks we map for direct IO at once. */ -#define DIO_MAX_BLOCKS 4096 -/* - * Number of credits we need for writing DIO_MAX_BLOCKS: - * We need sb + group descriptor + bitmap + inode -> 4 - * For B blocks with A block pointers per block we need: - * 1 (triple ind.) + (B/A/A + 2) (doubly ind.) + (B/A + 2) (indirect). - * If we plug in 4096 for B and 256 for A (for 1KB block size), we get 25. - */ -#define DIO_CREDITS 25 - -static int ext3_get_block(struct inode *inode, sector_t iblock, - struct buffer_head *bh_result, int create) -{ - handle_t *handle = ext3_journal_current_handle(); - int ret = 0, started = 0; - unsigned max_blocks = bh_result->b_size >> inode->i_blkbits; - - if (create && !handle) { /* Direct IO write... */ - if (max_blocks > DIO_MAX_BLOCKS) - max_blocks = DIO_MAX_BLOCKS; - handle = ext3_journal_start(inode, DIO_CREDITS + - EXT3_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb)); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - goto out; - } - started = 1; - } - - ret = ext3_get_blocks_handle(handle, inode, iblock, - max_blocks, bh_result, create); - if (ret > 0) { - bh_result->b_size = (ret << inode->i_blkbits); - ret = 0; - } - if (started) - ext3_journal_stop(handle); -out: - return ret; -} - -int ext3_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, - u64 start, u64 len) -{ - return generic_block_fiemap(inode, fieinfo, start, len, - ext3_get_block); -} - -/* - * `handle' can be NULL if create is zero - */ -struct buffer_head *ext3_getblk(handle_t *handle, struct inode *inode, - long block, int create, int *errp) -{ - struct buffer_head dummy; - int fatal = 0, err; - - J_ASSERT(handle != NULL || create == 0); - - dummy.b_state = 0; - dummy.b_blocknr = -1000; - buffer_trace_init(&dummy.b_history); - err = ext3_get_blocks_handle(handle, inode, block, 1, - &dummy, create); - /* - * ext3_get_blocks_handle() returns number of blocks - * mapped. 0 in case of a HOLE. - */ - if (err > 0) { - WARN_ON(err > 1); - err = 0; - } - *errp = err; - if (!err && buffer_mapped(&dummy)) { - struct buffer_head *bh; - bh = sb_getblk(inode->i_sb, dummy.b_blocknr); - if (unlikely(!bh)) { - *errp = -ENOMEM; - goto err; - } - if (buffer_new(&dummy)) { - J_ASSERT(create != 0); - J_ASSERT(handle != NULL); - - /* - * Now that we do not always journal data, we should - * keep in mind whether this should always journal the - * new buffer as metadata. For now, regular file - * writes use ext3_get_block instead, so it's not a - * problem. - */ - lock_buffer(bh); - BUFFER_TRACE(bh, "call get_create_access"); - fatal = ext3_journal_get_create_access(handle, bh); - if (!fatal && !buffer_uptodate(bh)) { - memset(bh->b_data,0,inode->i_sb->s_blocksize); - set_buffer_uptodate(bh); - } - unlock_buffer(bh); - BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); - err = ext3_journal_dirty_metadata(handle, bh); - if (!fatal) - fatal = err; - } else { - BUFFER_TRACE(bh, "not a new buffer"); - } - if (fatal) { - *errp = fatal; - brelse(bh); - bh = NULL; - } - return bh; - } -err: - return NULL; -} - -struct buffer_head *ext3_bread(handle_t *handle, struct inode *inode, - int block, int create, int *err) -{ - struct buffer_head * bh; - - bh = ext3_getblk(handle, inode, block, create, err); - if (!bh) - return bh; - if (bh_uptodate_or_lock(bh)) - return bh; - get_bh(bh); - bh->b_end_io = end_buffer_read_sync; - submit_bh(READ | REQ_META | REQ_PRIO, bh); - wait_on_buffer(bh); - if (buffer_uptodate(bh)) - return bh; - put_bh(bh); - *err = -EIO; - return NULL; -} - -static int walk_page_buffers( handle_t *handle, - struct buffer_head *head, - unsigned from, - unsigned to, - int *partial, - int (*fn)( handle_t *handle, - struct buffer_head *bh)) -{ - struct buffer_head *bh; - unsigned block_start, block_end; - unsigned blocksize = head->b_size; - int err, ret = 0; - struct buffer_head *next; - - for ( bh = head, block_start = 0; - ret == 0 && (bh != head || !block_start); - block_start = block_end, bh = next) - { - next = bh->b_this_page; - block_end = block_start + blocksize; - if (block_end <= from || block_start >= to) { - if (partial && !buffer_uptodate(bh)) - *partial = 1; - continue; - } - err = (*fn)(handle, bh); - if (!ret) - ret = err; - } - return ret; -} - -/* - * To preserve ordering, it is essential that the hole instantiation and - * the data write be encapsulated in a single transaction. We cannot - * close off a transaction and start a new one between the ext3_get_block() - * and the commit_write(). So doing the journal_start at the start of - * prepare_write() is the right place. - * - * Also, this function can nest inside ext3_writepage() -> - * block_write_full_page(). In that case, we *know* that ext3_writepage() - * has generated enough buffer credits to do the whole page. So we won't - * block on the journal in that case, which is good, because the caller may - * be PF_MEMALLOC. - * - * By accident, ext3 can be reentered when a transaction is open via - * quota file writes. If we were to commit the transaction while thus - * reentered, there can be a deadlock - we would be holding a quota - * lock, and the commit would never complete if another thread had a - * transaction open and was blocking on the quota lock - a ranking - * violation. - * - * So what we do is to rely on the fact that journal_stop/journal_start - * will _not_ run commit under these circumstances because handle->h_ref - * is elevated. We'll still have enough credits for the tiny quotafile - * write. - */ -static int do_journal_get_write_access(handle_t *handle, - struct buffer_head *bh) -{ - int dirty = buffer_dirty(bh); - int ret; - - if (!buffer_mapped(bh) || buffer_freed(bh)) - return 0; - /* - * __block_prepare_write() could have dirtied some buffers. Clean - * the dirty bit as jbd2_journal_get_write_access() could complain - * otherwise about fs integrity issues. Setting of the dirty bit - * by __block_prepare_write() isn't a real problem here as we clear - * the bit before releasing a page lock and thus writeback cannot - * ever write the buffer. - */ - if (dirty) - clear_buffer_dirty(bh); - ret = ext3_journal_get_write_access(handle, bh); - if (!ret && dirty) - ret = ext3_journal_dirty_metadata(handle, bh); - return ret; -} - -/* - * Truncate blocks that were not used by write. We have to truncate the - * pagecache as well so that corresponding buffers get properly unmapped. - */ -static void ext3_truncate_failed_write(struct inode *inode) -{ - truncate_inode_pages(inode->i_mapping, inode->i_size); - ext3_truncate(inode); -} - -/* - * Truncate blocks that were not used by direct IO write. We have to zero out - * the last file block as well because direct IO might have written to it. - */ -static void ext3_truncate_failed_direct_write(struct inode *inode) -{ - ext3_block_truncate_page(inode, inode->i_size); - ext3_truncate(inode); -} - -static int ext3_write_begin(struct file *file, struct address_space *mapping, - loff_t pos, unsigned len, unsigned flags, - struct page **pagep, void **fsdata) -{ - struct inode *inode = mapping->host; - int ret; - handle_t *handle; - int retries = 0; - struct page *page; - pgoff_t index; - unsigned from, to; - /* Reserve one block more for addition to orphan list in case - * we allocate blocks but write fails for some reason */ - int needed_blocks = ext3_writepage_trans_blocks(inode) + 1; - - trace_ext3_write_begin(inode, pos, len, flags); - - index = pos >> PAGE_CACHE_SHIFT; - from = pos & (PAGE_CACHE_SIZE - 1); - to = from + len; - -retry: - page = grab_cache_page_write_begin(mapping, index, flags); - if (!page) - return -ENOMEM; - *pagep = page; - - handle = ext3_journal_start(inode, needed_blocks); - if (IS_ERR(handle)) { - unlock_page(page); - page_cache_release(page); - ret = PTR_ERR(handle); - goto out; - } - ret = __block_write_begin(page, pos, len, ext3_get_block); - if (ret) - goto write_begin_failed; - - if (ext3_should_journal_data(inode)) { - ret = walk_page_buffers(handle, page_buffers(page), - from, to, NULL, do_journal_get_write_access); - } -write_begin_failed: - if (ret) { - /* - * block_write_begin may have instantiated a few blocks - * outside i_size. Trim these off again. Don't need - * i_size_read because we hold i_mutex. - * - * Add inode to orphan list in case we crash before truncate - * finishes. Do this only if ext3_can_truncate() agrees so - * that orphan processing code is happy. - */ - if (pos + len > inode->i_size && ext3_can_truncate(inode)) - ext3_orphan_add(handle, inode); - ext3_journal_stop(handle); - unlock_page(page); - page_cache_release(page); - if (pos + len > inode->i_size) - ext3_truncate_failed_write(inode); - } - if (ret == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries)) - goto retry; -out: - return ret; -} - - -int ext3_journal_dirty_data(handle_t *handle, struct buffer_head *bh) -{ - int err = journal_dirty_data(handle, bh); - if (err) - ext3_journal_abort_handle(__func__, __func__, - bh, handle, err); - return err; -} - -/* For ordered writepage and write_end functions */ -static int journal_dirty_data_fn(handle_t *handle, struct buffer_head *bh) -{ - /* - * Write could have mapped the buffer but it didn't copy the data in - * yet. So avoid filing such buffer into a transaction. - */ - if (buffer_mapped(bh) && buffer_uptodate(bh)) - return ext3_journal_dirty_data(handle, bh); - return 0; -} - -/* For write_end() in data=journal mode */ -static int write_end_fn(handle_t *handle, struct buffer_head *bh) -{ - if (!buffer_mapped(bh) || buffer_freed(bh)) - return 0; - set_buffer_uptodate(bh); - return ext3_journal_dirty_metadata(handle, bh); -} - -/* - * This is nasty and subtle: ext3_write_begin() could have allocated blocks - * for the whole page but later we failed to copy the data in. Update inode - * size according to what we managed to copy. The rest is going to be - * truncated in write_end function. - */ -static void update_file_sizes(struct inode *inode, loff_t pos, unsigned copied) -{ - /* What matters to us is i_disksize. We don't write i_size anywhere */ - if (pos + copied > inode->i_size) - i_size_write(inode, pos + copied); - if (pos + copied > EXT3_I(inode)->i_disksize) { - EXT3_I(inode)->i_disksize = pos + copied; - mark_inode_dirty(inode); - } -} - -/* - * We need to pick up the new inode size which generic_commit_write gave us - * `file' can be NULL - eg, when called from page_symlink(). - * - * ext3 never places buffers on inode->i_mapping->private_list. metadata - * buffers are managed internally. - */ -static int ext3_ordered_write_end(struct file *file, - struct address_space *mapping, - loff_t pos, unsigned len, unsigned copied, - struct page *page, void *fsdata) -{ - handle_t *handle = ext3_journal_current_handle(); - struct inode *inode = file->f_mapping->host; - unsigned from, to; - int ret = 0, ret2; - - trace_ext3_ordered_write_end(inode, pos, len, copied); - copied = block_write_end(file, mapping, pos, len, copied, page, fsdata); - - from = pos & (PAGE_CACHE_SIZE - 1); - to = from + copied; - ret = walk_page_buffers(handle, page_buffers(page), - from, to, NULL, journal_dirty_data_fn); - - if (ret == 0) - update_file_sizes(inode, pos, copied); - /* - * There may be allocated blocks outside of i_size because - * we failed to copy some data. Prepare for truncate. - */ - if (pos + len > inode->i_size && ext3_can_truncate(inode)) - ext3_orphan_add(handle, inode); - ret2 = ext3_journal_stop(handle); - if (!ret) - ret = ret2; - unlock_page(page); - page_cache_release(page); - - if (pos + len > inode->i_size) - ext3_truncate_failed_write(inode); - return ret ? ret : copied; -} - -static int ext3_writeback_write_end(struct file *file, - struct address_space *mapping, - loff_t pos, unsigned len, unsigned copied, - struct page *page, void *fsdata) -{ - handle_t *handle = ext3_journal_current_handle(); - struct inode *inode = file->f_mapping->host; - int ret; - - trace_ext3_writeback_write_end(inode, pos, len, copied); - copied = block_write_end(file, mapping, pos, len, copied, page, fsdata); - update_file_sizes(inode, pos, copied); - /* - * There may be allocated blocks outside of i_size because - * we failed to copy some data. Prepare for truncate. - */ - if (pos + len > inode->i_size && ext3_can_truncate(inode)) - ext3_orphan_add(handle, inode); - ret = ext3_journal_stop(handle); - unlock_page(page); - page_cache_release(page); - - if (pos + len > inode->i_size) - ext3_truncate_failed_write(inode); - return ret ? ret : copied; -} - -static int ext3_journalled_write_end(struct file *file, - struct address_space *mapping, - loff_t pos, unsigned len, unsigned copied, - struct page *page, void *fsdata) -{ - handle_t *handle = ext3_journal_current_handle(); - struct inode *inode = mapping->host; - struct ext3_inode_info *ei = EXT3_I(inode); - int ret = 0, ret2; - int partial = 0; - unsigned from, to; - - trace_ext3_journalled_write_end(inode, pos, len, copied); - from = pos & (PAGE_CACHE_SIZE - 1); - to = from + len; - - if (copied < len) { - if (!PageUptodate(page)) - copied = 0; - page_zero_new_buffers(page, from + copied, to); - to = from + copied; - } - - ret = walk_page_buffers(handle, page_buffers(page), from, - to, &partial, write_end_fn); - if (!partial) - SetPageUptodate(page); - - if (pos + copied > inode->i_size) - i_size_write(inode, pos + copied); - /* - * There may be allocated blocks outside of i_size because - * we failed to copy some data. Prepare for truncate. - */ - if (pos + len > inode->i_size && ext3_can_truncate(inode)) - ext3_orphan_add(handle, inode); - ext3_set_inode_state(inode, EXT3_STATE_JDATA); - atomic_set(&ei->i_datasync_tid, handle->h_transaction->t_tid); - if (inode->i_size > ei->i_disksize) { - ei->i_disksize = inode->i_size; - ret2 = ext3_mark_inode_dirty(handle, inode); - if (!ret) - ret = ret2; - } - - ret2 = ext3_journal_stop(handle); - if (!ret) - ret = ret2; - unlock_page(page); - page_cache_release(page); - - if (pos + len > inode->i_size) - ext3_truncate_failed_write(inode); - return ret ? ret : copied; -} - -/* - * bmap() is special. It gets used by applications such as lilo and by - * the swapper to find the on-disk block of a specific piece of data. - * - * Naturally, this is dangerous if the block concerned is still in the - * journal. If somebody makes a swapfile on an ext3 data-journaling - * filesystem and enables swap, then they may get a nasty shock when the - * data getting swapped to that swapfile suddenly gets overwritten by - * the original zero's written out previously to the journal and - * awaiting writeback in the kernel's buffer cache. - * - * So, if we see any bmap calls here on a modified, data-journaled file, - * take extra steps to flush any blocks which might be in the cache. - */ -static sector_t ext3_bmap(struct address_space *mapping, sector_t block) -{ - struct inode *inode = mapping->host; - journal_t *journal; - int err; - - if (ext3_test_inode_state(inode, EXT3_STATE_JDATA)) { - /* - * This is a REALLY heavyweight approach, but the use of - * bmap on dirty files is expected to be extremely rare: - * only if we run lilo or swapon on a freshly made file - * do we expect this to happen. - * - * (bmap requires CAP_SYS_RAWIO so this does not - * represent an unprivileged user DOS attack --- we'd be - * in trouble if mortal users could trigger this path at - * will.) - * - * NB. EXT3_STATE_JDATA is not set on files other than - * regular files. If somebody wants to bmap a directory - * or symlink and gets confused because the buffer - * hasn't yet been flushed to disk, they deserve - * everything they get. - */ - - ext3_clear_inode_state(inode, EXT3_STATE_JDATA); - journal = EXT3_JOURNAL(inode); - journal_lock_updates(journal); - err = journal_flush(journal); - journal_unlock_updates(journal); - - if (err) - return 0; - } - - return generic_block_bmap(mapping,block,ext3_get_block); -} - -static int bget_one(handle_t *handle, struct buffer_head *bh) -{ - get_bh(bh); - return 0; -} - -static int bput_one(handle_t *handle, struct buffer_head *bh) -{ - put_bh(bh); - return 0; -} - -static int buffer_unmapped(handle_t *handle, struct buffer_head *bh) -{ - return !buffer_mapped(bh); -} - -/* - * Note that whenever we need to map blocks we start a transaction even if - * we're not journalling data. This is to preserve ordering: any hole - * instantiation within __block_write_full_page -> ext3_get_block() should be - * journalled along with the data so we don't crash and then get metadata which - * refers to old data. - * - * In all journalling modes block_write_full_page() will start the I/O. - * - * We don't honour synchronous mounts for writepage(). That would be - * disastrous. Any write() or metadata operation will sync the fs for - * us. - */ -static int ext3_ordered_writepage(struct page *page, - struct writeback_control *wbc) -{ - struct inode *inode = page->mapping->host; - struct buffer_head *page_bufs; - handle_t *handle = NULL; - int ret = 0; - int err; - - J_ASSERT(PageLocked(page)); - /* - * We don't want to warn for emergency remount. The condition is - * ordered to avoid dereferencing inode->i_sb in non-error case to - * avoid slow-downs. - */ - WARN_ON_ONCE(IS_RDONLY(inode) && - !(EXT3_SB(inode->i_sb)->s_mount_state & EXT3_ERROR_FS)); - - /* - * We give up here if we're reentered, because it might be for a - * different filesystem. - */ - if (ext3_journal_current_handle()) - goto out_fail; - - trace_ext3_ordered_writepage(page); - if (!page_has_buffers(page)) { - create_empty_buffers(page, inode->i_sb->s_blocksize, - (1 << BH_Dirty)|(1 << BH_Uptodate)); - page_bufs = page_buffers(page); - } else { - page_bufs = page_buffers(page); - if (!walk_page_buffers(NULL, page_bufs, 0, PAGE_CACHE_SIZE, - NULL, buffer_unmapped)) { - /* Provide NULL get_block() to catch bugs if buffers - * weren't really mapped */ - return block_write_full_page(page, NULL, wbc); - } - } - handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode)); - - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - goto out_fail; - } - - walk_page_buffers(handle, page_bufs, 0, - PAGE_CACHE_SIZE, NULL, bget_one); - - ret = block_write_full_page(page, ext3_get_block, wbc); - - /* - * The page can become unlocked at any point now, and - * truncate can then come in and change things. So we - * can't touch *page from now on. But *page_bufs is - * safe due to elevated refcount. - */ - - /* - * And attach them to the current transaction. But only if - * block_write_full_page() succeeded. Otherwise they are unmapped, - * and generally junk. - */ - if (ret == 0) - ret = walk_page_buffers(handle, page_bufs, 0, PAGE_CACHE_SIZE, - NULL, journal_dirty_data_fn); - walk_page_buffers(handle, page_bufs, 0, - PAGE_CACHE_SIZE, NULL, bput_one); - err = ext3_journal_stop(handle); - if (!ret) - ret = err; - return ret; - -out_fail: - redirty_page_for_writepage(wbc, page); - unlock_page(page); - return ret; -} - -static int ext3_writeback_writepage(struct page *page, - struct writeback_control *wbc) -{ - struct inode *inode = page->mapping->host; - handle_t *handle = NULL; - int ret = 0; - int err; - - J_ASSERT(PageLocked(page)); - /* - * We don't want to warn for emergency remount. The condition is - * ordered to avoid dereferencing inode->i_sb in non-error case to - * avoid slow-downs. - */ - WARN_ON_ONCE(IS_RDONLY(inode) && - !(EXT3_SB(inode->i_sb)->s_mount_state & EXT3_ERROR_FS)); - - if (ext3_journal_current_handle()) - goto out_fail; - - trace_ext3_writeback_writepage(page); - if (page_has_buffers(page)) { - if (!walk_page_buffers(NULL, page_buffers(page), 0, - PAGE_CACHE_SIZE, NULL, buffer_unmapped)) { - /* Provide NULL get_block() to catch bugs if buffers - * weren't really mapped */ - return block_write_full_page(page, NULL, wbc); - } - } - - handle = ext3_journal_start(inode, ext3_writepage_trans_blocks(inode)); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - goto out_fail; - } - - ret = block_write_full_page(page, ext3_get_block, wbc); - - err = ext3_journal_stop(handle); - if (!ret) - ret = err; - return ret; - -out_fail: - redirty_page_for_writepage(wbc, page); - unlock_page(page); - return ret; -} - -static int ext3_journalled_writepage(struct page *page, - struct writeback_control *wbc) -{ - struct inode *inode = page->mapping->host; - handle_t *handle = NULL; - int ret = 0; - int err; - - J_ASSERT(PageLocked(page)); - /* - * We don't want to warn for emergency remount. The condition is - * ordered to avoid dereferencing inode->i_sb in non-error case to - * avoid slow-downs. - */ - WARN_ON_ONCE(IS_RDONLY(inode) && - !(EXT3_SB(inode->i_sb)->s_mount_state & EXT3_ERROR_FS)); - - trace_ext3_journalled_writepage(page); - if (!page_has_buffers(page) || PageChecked(page)) { - if (ext3_journal_current_handle()) - goto no_write; - - handle = ext3_journal_start(inode, - ext3_writepage_trans_blocks(inode)); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - goto no_write; - } - /* - * It's mmapped pagecache. Add buffers and journal it. There - * doesn't seem much point in redirtying the page here. - */ - ClearPageChecked(page); - ret = __block_write_begin(page, 0, PAGE_CACHE_SIZE, - ext3_get_block); - if (ret != 0) { - ext3_journal_stop(handle); - goto out_unlock; - } - ret = walk_page_buffers(handle, page_buffers(page), 0, - PAGE_CACHE_SIZE, NULL, do_journal_get_write_access); - - err = walk_page_buffers(handle, page_buffers(page), 0, - PAGE_CACHE_SIZE, NULL, write_end_fn); - if (ret == 0) - ret = err; - ext3_set_inode_state(inode, EXT3_STATE_JDATA); - atomic_set(&EXT3_I(inode)->i_datasync_tid, - handle->h_transaction->t_tid); - unlock_page(page); - err = ext3_journal_stop(handle); - if (!ret) - ret = err; - } else { - /* - * It is a page full of checkpoint-mode buffers. Go and write - * them. They should have been already mapped when they went - * to the journal so provide NULL get_block function to catch - * errors. - */ - ret = block_write_full_page(page, NULL, wbc); - } -out: - return ret; - -no_write: - redirty_page_for_writepage(wbc, page); -out_unlock: - unlock_page(page); - goto out; -} - -static int ext3_readpage(struct file *file, struct page *page) -{ - trace_ext3_readpage(page); - return mpage_readpage(page, ext3_get_block); -} - -static int -ext3_readpages(struct file *file, struct address_space *mapping, - struct list_head *pages, unsigned nr_pages) -{ - return mpage_readpages(mapping, pages, nr_pages, ext3_get_block); -} - -static void ext3_invalidatepage(struct page *page, unsigned int offset, - unsigned int length) -{ - journal_t *journal = EXT3_JOURNAL(page->mapping->host); - - trace_ext3_invalidatepage(page, offset, length); - - /* - * If it's a full truncate we just forget about the pending dirtying - */ - if (offset == 0 && length == PAGE_CACHE_SIZE) - ClearPageChecked(page); - - journal_invalidatepage(journal, page, offset, length); -} - -static int ext3_releasepage(struct page *page, gfp_t wait) -{ - journal_t *journal = EXT3_JOURNAL(page->mapping->host); - - trace_ext3_releasepage(page); - WARN_ON(PageChecked(page)); - if (!page_has_buffers(page)) - return 0; - return journal_try_to_free_buffers(journal, page, wait); -} - -/* - * If the O_DIRECT write will extend the file then add this inode to the - * orphan list. So recovery will truncate it back to the original size - * if the machine crashes during the write. - * - * If the O_DIRECT write is intantiating holes inside i_size and the machine - * crashes then stale disk data _may_ be exposed inside the file. But current - * VFS code falls back into buffered path in that case so we are safe. - */ -static ssize_t ext3_direct_IO(struct kiocb *iocb, struct iov_iter *iter, - loff_t offset) -{ - struct file *file = iocb->ki_filp; - struct inode *inode = file->f_mapping->host; - struct ext3_inode_info *ei = EXT3_I(inode); - handle_t *handle; - ssize_t ret; - int orphan = 0; - size_t count = iov_iter_count(iter); - int retries = 0; - - trace_ext3_direct_IO_enter(inode, offset, count, iov_iter_rw(iter)); - - if (iov_iter_rw(iter) == WRITE) { - loff_t final_size = offset + count; - - if (final_size > inode->i_size) { - /* Credits for sb + inode write */ - handle = ext3_journal_start(inode, 2); - if (IS_ERR(handle)) { - ret = PTR_ERR(handle); - goto out; - } - ret = ext3_orphan_add(handle, inode); - if (ret) { - ext3_journal_stop(handle); - goto out; - } - orphan = 1; - ei->i_disksize = inode->i_size; - ext3_journal_stop(handle); - } - } - -retry: - ret = blockdev_direct_IO(iocb, inode, iter, offset, ext3_get_block); - /* - * In case of error extending write may have instantiated a few - * blocks outside i_size. Trim these off again. - */ - if (unlikely(iov_iter_rw(iter) == WRITE && ret < 0)) { - loff_t isize = i_size_read(inode); - loff_t end = offset + count; - - if (end > isize) - ext3_truncate_failed_direct_write(inode); - } - if (ret == -ENOSPC && ext3_should_retry_alloc(inode->i_sb, &retries)) - goto retry; - - if (orphan) { - int err; - - /* Credits for sb + inode write */ - handle = ext3_journal_start(inode, 2); - if (IS_ERR(handle)) { - /* This is really bad luck. We've written the data - * but cannot extend i_size. Truncate allocated blocks - * and pretend the write failed... */ - ext3_truncate_failed_direct_write(inode); - ret = PTR_ERR(handle); - if (inode->i_nlink) - ext3_orphan_del(NULL, inode); - goto out; - } - if (inode->i_nlink) - ext3_orphan_del(handle, inode); - if (ret > 0) { - loff_t end = offset + ret; - if (end > inode->i_size) { - ei->i_disksize = end; - i_size_write(inode, end); - /* - * We're going to return a positive `ret' - * here due to non-zero-length I/O, so there's - * no way of reporting error returns from - * ext3_mark_inode_dirty() to userspace. So - * ignore it. - */ - ext3_mark_inode_dirty(handle, inode); - } - } - err = ext3_journal_stop(handle); - if (ret == 0) - ret = err; - } -out: - trace_ext3_direct_IO_exit(inode, offset, count, iov_iter_rw(iter), ret); - return ret; -} - -/* - * Pages can be marked dirty completely asynchronously from ext3's journalling - * activity. By filemap_sync_pte(), try_to_unmap_one(), etc. We cannot do - * much here because ->set_page_dirty is called under VFS locks. The page is - * not necessarily locked. - * - * We cannot just dirty the page and leave attached buffers clean, because the - * buffers' dirty state is "definitive". We cannot just set the buffers dirty - * or jbddirty because all the journalling code will explode. - * - * So what we do is to mark the page "pending dirty" and next time writepage - * is called, propagate that into the buffers appropriately. - */ -static int ext3_journalled_set_page_dirty(struct page *page) -{ - SetPageChecked(page); - return __set_page_dirty_nobuffers(page); -} - -static const struct address_space_operations ext3_ordered_aops = { - .readpage = ext3_readpage, - .readpages = ext3_readpages, - .writepage = ext3_ordered_writepage, - .write_begin = ext3_write_begin, - .write_end = ext3_ordered_write_end, - .bmap = ext3_bmap, - .invalidatepage = ext3_invalidatepage, - .releasepage = ext3_releasepage, - .direct_IO = ext3_direct_IO, - .migratepage = buffer_migrate_page, - .is_partially_uptodate = block_is_partially_uptodate, - .is_dirty_writeback = buffer_check_dirty_writeback, - .error_remove_page = generic_error_remove_page, -}; - -static const struct address_space_operations ext3_writeback_aops = { - .readpage = ext3_readpage, - .readpages = ext3_readpages, - .writepage = ext3_writeback_writepage, - .write_begin = ext3_write_begin, - .write_end = ext3_writeback_write_end, - .bmap = ext3_bmap, - .invalidatepage = ext3_invalidatepage, - .releasepage = ext3_releasepage, - .direct_IO = ext3_direct_IO, - .migratepage = buffer_migrate_page, - .is_partially_uptodate = block_is_partially_uptodate, - .error_remove_page = generic_error_remove_page, -}; - -static const struct address_space_operations ext3_journalled_aops = { - .readpage = ext3_readpage, - .readpages = ext3_readpages, - .writepage = ext3_journalled_writepage, - .write_begin = ext3_write_begin, - .write_end = ext3_journalled_write_end, - .set_page_dirty = ext3_journalled_set_page_dirty, - .bmap = ext3_bmap, - .invalidatepage = ext3_invalidatepage, - .releasepage = ext3_releasepage, - .is_partially_uptodate = block_is_partially_uptodate, - .error_remove_page = generic_error_remove_page, -}; - -void ext3_set_aops(struct inode *inode) -{ - if (ext3_should_order_data(inode)) - inode->i_mapping->a_ops = &ext3_ordered_aops; - else if (ext3_should_writeback_data(inode)) - inode->i_mapping->a_ops = &ext3_writeback_aops; - else - inode->i_mapping->a_ops = &ext3_journalled_aops; -} - -/* - * ext3_block_truncate_page() zeroes out a mapping from file offset `from' - * up to the end of the block which corresponds to `from'. - * This required during truncate. We need to physically zero the tail end - * of that block so it doesn't yield old data if the file is later grown. - */ -static int ext3_block_truncate_page(struct inode *inode, loff_t from) -{ - ext3_fsblk_t index = from >> PAGE_CACHE_SHIFT; - unsigned offset = from & (PAGE_CACHE_SIZE - 1); - unsigned blocksize, iblock, length, pos; - struct page *page; - handle_t *handle = NULL; - struct buffer_head *bh; - int err = 0; - - /* Truncated on block boundary - nothing to do */ - blocksize = inode->i_sb->s_blocksize; - if ((from & (blocksize - 1)) == 0) - return 0; - - page = grab_cache_page(inode->i_mapping, index); - if (!page) - return -ENOMEM; - length = blocksize - (offset & (blocksize - 1)); - iblock = index << (PAGE_CACHE_SHIFT - inode->i_sb->s_blocksize_bits); - - if (!page_has_buffers(page)) - create_empty_buffers(page, blocksize, 0); - - /* Find the buffer that contains "offset" */ - bh = page_buffers(page); - pos = blocksize; - while (offset >= pos) { - bh = bh->b_this_page; - iblock++; - pos += blocksize; - } - - err = 0; - if (buffer_freed(bh)) { - BUFFER_TRACE(bh, "freed: skip"); - goto unlock; - } - - if (!buffer_mapped(bh)) { - BUFFER_TRACE(bh, "unmapped"); - ext3_get_block(inode, iblock, bh, 0); - /* unmapped? It's a hole - nothing to do */ - if (!buffer_mapped(bh)) { - BUFFER_TRACE(bh, "still unmapped"); - goto unlock; - } - } - - /* Ok, it's mapped. Make sure it's up-to-date */ - if (PageUptodate(page)) - set_buffer_uptodate(bh); - - if (!bh_uptodate_or_lock(bh)) { - err = bh_submit_read(bh); - /* Uhhuh. Read error. Complain and punt. */ - if (err) - goto unlock; - } - - /* data=writeback mode doesn't need transaction to zero-out data */ - if (!ext3_should_writeback_data(inode)) { - /* We journal at most one block */ - handle = ext3_journal_start(inode, 1); - if (IS_ERR(handle)) { - clear_highpage(page); - flush_dcache_page(page); - err = PTR_ERR(handle); - goto unlock; - } - } - - if (ext3_should_journal_data(inode)) { - BUFFER_TRACE(bh, "get write access"); - err = ext3_journal_get_write_access(handle, bh); - if (err) - goto stop; - } - - zero_user(page, offset, length); - BUFFER_TRACE(bh, "zeroed end of block"); - - err = 0; - if (ext3_should_journal_data(inode)) { - err = ext3_journal_dirty_metadata(handle, bh); - } else { - if (ext3_should_order_data(inode)) - err = ext3_journal_dirty_data(handle, bh); - mark_buffer_dirty(bh); - } -stop: - if (handle) - ext3_journal_stop(handle); - -unlock: - unlock_page(page); - page_cache_release(page); - return err; -} - -/* - * Probably it should be a library function... search for first non-zero word - * or memcmp with zero_page, whatever is better for particular architecture. - * Linus? - */ -static inline int all_zeroes(__le32 *p, __le32 *q) -{ - while (p < q) - if (*p++) - return 0; - return 1; -} - -/** - * ext3_find_shared - find the indirect blocks for partial truncation. - * @inode: inode in question - * @depth: depth of the affected branch - * @offsets: offsets of pointers in that branch (see ext3_block_to_path) - * @chain: place to store the pointers to partial indirect blocks - * @top: place to the (detached) top of branch - * - * This is a helper function used by ext3_truncate(). - * - * When we do truncate() we may have to clean the ends of several - * indirect blocks but leave the blocks themselves alive. Block is - * partially truncated if some data below the new i_size is referred - * from it (and it is on the path to the first completely truncated - * data block, indeed). We have to free the top of that path along - * with everything to the right of the path. Since no allocation - * past the truncation point is possible until ext3_truncate() - * finishes, we may safely do the latter, but top of branch may - * require special attention - pageout below the truncation point - * might try to populate it. - * - * We atomically detach the top of branch from the tree, store the - * block number of its root in *@top, pointers to buffer_heads of - * partially truncated blocks - in @chain[].bh and pointers to - * their last elements that should not be removed - in - * @chain[].p. Return value is the pointer to last filled element - * of @chain. - * - * The work left to caller to do the actual freeing of subtrees: - * a) free the subtree starting from *@top - * b) free the subtrees whose roots are stored in - * (@chain[i].p+1 .. end of @chain[i].bh->b_data) - * c) free the subtrees growing from the inode past the @chain[0]. - * (no partially truncated stuff there). */ - -static Indirect *ext3_find_shared(struct inode *inode, int depth, - int offsets[4], Indirect chain[4], __le32 *top) -{ - Indirect *partial, *p; - int k, err; - - *top = 0; - /* Make k index the deepest non-null offset + 1 */ - for (k = depth; k > 1 && !offsets[k-1]; k--) - ; - partial = ext3_get_branch(inode, k, offsets, chain, &err); - /* Writer: pointers */ - if (!partial) - partial = chain + k-1; - /* - * If the branch acquired continuation since we've looked at it - - * fine, it should all survive and (new) top doesn't belong to us. - */ - if (!partial->key && *partial->p) - /* Writer: end */ - goto no_top; - for (p=partial; p>chain && all_zeroes((__le32*)p->bh->b_data,p->p); p--) - ; - /* - * OK, we've found the last block that must survive. The rest of our - * branch should be detached before unlocking. However, if that rest - * of branch is all ours and does not grow immediately from the inode - * it's easier to cheat and just decrement partial->p. - */ - if (p == chain + k - 1 && p > chain) { - p->p--; - } else { - *top = *p->p; - /* Nope, don't do this in ext3. Must leave the tree intact */ -#if 0 - *p->p = 0; -#endif - } - /* Writer: end */ - - while(partial > p) { - brelse(partial->bh); - partial--; - } -no_top: - return partial; -} - -/* - * Zero a number of block pointers in either an inode or an indirect block. - * If we restart the transaction we must again get write access to the - * indirect block for further modification. - * - * We release `count' blocks on disk, but (last - first) may be greater - * than `count' because there can be holes in there. - */ -static void ext3_clear_blocks(handle_t *handle, struct inode *inode, - struct buffer_head *bh, ext3_fsblk_t block_to_free, - unsigned long count, __le32 *first, __le32 *last) -{ - __le32 *p; - if (try_to_extend_transaction(handle, inode)) { - if (bh) { - BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); - if (ext3_journal_dirty_metadata(handle, bh)) - return; - } - ext3_mark_inode_dirty(handle, inode); - truncate_restart_transaction(handle, inode); - if (bh) { - BUFFER_TRACE(bh, "retaking write access"); - if (ext3_journal_get_write_access(handle, bh)) - return; - } - } - - /* - * Any buffers which are on the journal will be in memory. We find - * them on the hash table so journal_revoke() will run journal_forget() - * on them. We've already detached each block from the file, so - * bforget() in journal_forget() should be safe. - * - * AKPM: turn on bforget in journal_forget()!!! - */ - for (p = first; p < last; p++) { - u32 nr = le32_to_cpu(*p); - if (nr) { - struct buffer_head *bh; - - *p = 0; - bh = sb_find_get_block(inode->i_sb, nr); - ext3_forget(handle, 0, inode, bh, nr); - } - } - - ext3_free_blocks(handle, inode, block_to_free, count); -} - -/** - * ext3_free_data - free a list of data blocks - * @handle: handle for this transaction - * @inode: inode we are dealing with - * @this_bh: indirect buffer_head which contains *@first and *@last - * @first: array of block numbers - * @last: points immediately past the end of array - * - * We are freeing all blocks referred from that array (numbers are stored as - * little-endian 32-bit) and updating @inode->i_blocks appropriately. - * - * We accumulate contiguous runs of blocks to free. Conveniently, if these - * blocks are contiguous then releasing them at one time will only affect one - * or two bitmap blocks (+ group descriptor(s) and superblock) and we won't - * actually use a lot of journal space. - * - * @this_bh will be %NULL if @first and @last point into the inode's direct - * block pointers. - */ -static void ext3_free_data(handle_t *handle, struct inode *inode, - struct buffer_head *this_bh, - __le32 *first, __le32 *last) -{ - ext3_fsblk_t block_to_free = 0; /* Starting block # of a run */ - unsigned long count = 0; /* Number of blocks in the run */ - __le32 *block_to_free_p = NULL; /* Pointer into inode/ind - corresponding to - block_to_free */ - ext3_fsblk_t nr; /* Current block # */ - __le32 *p; /* Pointer into inode/ind - for current block */ - int err; - - if (this_bh) { /* For indirect block */ - BUFFER_TRACE(this_bh, "get_write_access"); - err = ext3_journal_get_write_access(handle, this_bh); - /* Important: if we can't update the indirect pointers - * to the blocks, we can't free them. */ - if (err) - return; - } - - for (p = first; p < last; p++) { - nr = le32_to_cpu(*p); - if (nr) { - /* accumulate blocks to free if they're contiguous */ - if (count == 0) { - block_to_free = nr; - block_to_free_p = p; - count = 1; - } else if (nr == block_to_free + count) { - count++; - } else { - ext3_clear_blocks(handle, inode, this_bh, - block_to_free, - count, block_to_free_p, p); - block_to_free = nr; - block_to_free_p = p; - count = 1; - } - } - } - - if (count > 0) - ext3_clear_blocks(handle, inode, this_bh, block_to_free, - count, block_to_free_p, p); - - if (this_bh) { - BUFFER_TRACE(this_bh, "call ext3_journal_dirty_metadata"); - - /* - * The buffer head should have an attached journal head at this - * point. However, if the data is corrupted and an indirect - * block pointed to itself, it would have been detached when - * the block was cleared. Check for this instead of OOPSing. - */ - if (bh2jh(this_bh)) - ext3_journal_dirty_metadata(handle, this_bh); - else - ext3_error(inode->i_sb, "ext3_free_data", - "circular indirect block detected, " - "inode=%lu, block=%llu", - inode->i_ino, - (unsigned long long)this_bh->b_blocknr); - } -} - -/** - * ext3_free_branches - free an array of branches - * @handle: JBD handle for this transaction - * @inode: inode we are dealing with - * @parent_bh: the buffer_head which contains *@first and *@last - * @first: array of block numbers - * @last: pointer immediately past the end of array - * @depth: depth of the branches to free - * - * We are freeing all blocks referred from these branches (numbers are - * stored as little-endian 32-bit) and updating @inode->i_blocks - * appropriately. - */ -static void ext3_free_branches(handle_t *handle, struct inode *inode, - struct buffer_head *parent_bh, - __le32 *first, __le32 *last, int depth) -{ - ext3_fsblk_t nr; - __le32 *p; - - if (is_handle_aborted(handle)) - return; - - if (depth--) { - struct buffer_head *bh; - int addr_per_block = EXT3_ADDR_PER_BLOCK(inode->i_sb); - p = last; - while (--p >= first) { - nr = le32_to_cpu(*p); - if (!nr) - continue; /* A hole */ - - /* Go read the buffer for the next level down */ - bh = sb_bread(inode->i_sb, nr); - - /* - * A read failure? Report error and clear slot - * (should be rare). - */ - if (!bh) { - ext3_error(inode->i_sb, "ext3_free_branches", - "Read failure, inode=%lu, block="E3FSBLK, - inode->i_ino, nr); - continue; - } - - /* This zaps the entire block. Bottom up. */ - BUFFER_TRACE(bh, "free child branches"); - ext3_free_branches(handle, inode, bh, - (__le32*)bh->b_data, - (__le32*)bh->b_data + addr_per_block, - depth); - - /* - * Everything below this this pointer has been - * released. Now let this top-of-subtree go. - * - * We want the freeing of this indirect block to be - * atomic in the journal with the updating of the - * bitmap block which owns it. So make some room in - * the journal. - * - * We zero the parent pointer *after* freeing its - * pointee in the bitmaps, so if extend_transaction() - * for some reason fails to put the bitmap changes and - * the release into the same transaction, recovery - * will merely complain about releasing a free block, - * rather than leaking blocks. - */ - if (is_handle_aborted(handle)) - return; - if (try_to_extend_transaction(handle, inode)) { - ext3_mark_inode_dirty(handle, inode); - truncate_restart_transaction(handle, inode); - } - - /* - * We've probably journalled the indirect block several - * times during the truncate. But it's no longer - * needed and we now drop it from the transaction via - * journal_revoke(). - * - * That's easy if it's exclusively part of this - * transaction. But if it's part of the committing - * transaction then journal_forget() will simply - * brelse() it. That means that if the underlying - * block is reallocated in ext3_get_block(), - * unmap_underlying_metadata() will find this block - * and will try to get rid of it. damn, damn. Thus - * we don't allow a block to be reallocated until - * a transaction freeing it has fully committed. - * - * We also have to make sure journal replay after a - * crash does not overwrite non-journaled data blocks - * with old metadata when the block got reallocated for - * data. Thus we have to store a revoke record for a - * block in the same transaction in which we free the - * block. - */ - ext3_forget(handle, 1, inode, bh, bh->b_blocknr); - - ext3_free_blocks(handle, inode, nr, 1); - - if (parent_bh) { - /* - * The block which we have just freed is - * pointed to by an indirect block: journal it - */ - BUFFER_TRACE(parent_bh, "get_write_access"); - if (!ext3_journal_get_write_access(handle, - parent_bh)){ - *p = 0; - BUFFER_TRACE(parent_bh, - "call ext3_journal_dirty_metadata"); - ext3_journal_dirty_metadata(handle, - parent_bh); - } - } - } - } else { - /* We have reached the bottom of the tree. */ - BUFFER_TRACE(parent_bh, "free data blocks"); - ext3_free_data(handle, inode, parent_bh, first, last); - } -} - -int ext3_can_truncate(struct inode *inode) -{ - if (S_ISREG(inode->i_mode)) - return 1; - if (S_ISDIR(inode->i_mode)) - return 1; - if (S_ISLNK(inode->i_mode)) - return !ext3_inode_is_fast_symlink(inode); - return 0; -} - -/* - * ext3_truncate() - * - * We block out ext3_get_block() block instantiations across the entire - * transaction, and VFS/VM ensures that ext3_truncate() cannot run - * simultaneously on behalf of the same inode. - * - * As we work through the truncate and commit bits of it to the journal there - * is one core, guiding principle: the file's tree must always be consistent on - * disk. We must be able to restart the truncate after a crash. - * - * The file's tree may be transiently inconsistent in memory (although it - * probably isn't), but whenever we close off and commit a journal transaction, - * the contents of (the filesystem + the journal) must be consistent and - * restartable. It's pretty simple, really: bottom up, right to left (although - * left-to-right works OK too). - * - * Note that at recovery time, journal replay occurs *before* the restart of - * truncate against the orphan inode list. - * - * The committed inode has the new, desired i_size (which is the same as - * i_disksize in this case). After a crash, ext3_orphan_cleanup() will see - * that this inode's truncate did not complete and it will again call - * ext3_truncate() to have another go. So there will be instantiated blocks - * to the right of the truncation point in a crashed ext3 filesystem. But - * that's fine - as long as they are linked from the inode, the post-crash - * ext3_truncate() run will find them and release them. - */ -void ext3_truncate(struct inode *inode) -{ - handle_t *handle; - struct ext3_inode_info *ei = EXT3_I(inode); - __le32 *i_data = ei->i_data; - int addr_per_block = EXT3_ADDR_PER_BLOCK(inode->i_sb); - int offsets[4]; - Indirect chain[4]; - Indirect *partial; - __le32 nr = 0; - int n; - long last_block; - unsigned blocksize = inode->i_sb->s_blocksize; - - trace_ext3_truncate_enter(inode); - - if (!ext3_can_truncate(inode)) - goto out_notrans; - - if (inode->i_size == 0 && ext3_should_writeback_data(inode)) - ext3_set_inode_state(inode, EXT3_STATE_FLUSH_ON_CLOSE); - - handle = start_transaction(inode); - if (IS_ERR(handle)) - goto out_notrans; - - last_block = (inode->i_size + blocksize-1) - >> EXT3_BLOCK_SIZE_BITS(inode->i_sb); - n = ext3_block_to_path(inode, last_block, offsets, NULL); - if (n == 0) - goto out_stop; /* error */ - - /* - * OK. This truncate is going to happen. We add the inode to the - * orphan list, so that if this truncate spans multiple transactions, - * and we crash, we will resume the truncate when the filesystem - * recovers. It also marks the inode dirty, to catch the new size. - * - * Implication: the file must always be in a sane, consistent - * truncatable state while each transaction commits. - */ - if (ext3_orphan_add(handle, inode)) - goto out_stop; - - /* - * The orphan list entry will now protect us from any crash which - * occurs before the truncate completes, so it is now safe to propagate - * the new, shorter inode size (held for now in i_size) into the - * on-disk inode. We do this via i_disksize, which is the value which - * ext3 *really* writes onto the disk inode. - */ - ei->i_disksize = inode->i_size; - - /* - * From here we block out all ext3_get_block() callers who want to - * modify the block allocation tree. - */ - mutex_lock(&ei->truncate_mutex); - - if (n == 1) { /* direct blocks */ - ext3_free_data(handle, inode, NULL, i_data+offsets[0], - i_data + EXT3_NDIR_BLOCKS); - goto do_indirects; - } - - partial = ext3_find_shared(inode, n, offsets, chain, &nr); - /* Kill the top of shared branch (not detached) */ - if (nr) { - if (partial == chain) { - /* Shared branch grows from the inode */ - ext3_free_branches(handle, inode, NULL, - &nr, &nr+1, (chain+n-1) - partial); - *partial->p = 0; - /* - * We mark the inode dirty prior to restart, - * and prior to stop. No need for it here. - */ - } else { - /* Shared branch grows from an indirect block */ - ext3_free_branches(handle, inode, partial->bh, - partial->p, - partial->p+1, (chain+n-1) - partial); - } - } - /* Clear the ends of indirect blocks on the shared branch */ - while (partial > chain) { - ext3_free_branches(handle, inode, partial->bh, partial->p + 1, - (__le32*)partial->bh->b_data+addr_per_block, - (chain+n-1) - partial); - BUFFER_TRACE(partial->bh, "call brelse"); - brelse (partial->bh); - partial--; - } -do_indirects: - /* Kill the remaining (whole) subtrees */ - switch (offsets[0]) { - default: - nr = i_data[EXT3_IND_BLOCK]; - if (nr) { - ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 1); - i_data[EXT3_IND_BLOCK] = 0; - } - case EXT3_IND_BLOCK: - nr = i_data[EXT3_DIND_BLOCK]; - if (nr) { - ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 2); - i_data[EXT3_DIND_BLOCK] = 0; - } - case EXT3_DIND_BLOCK: - nr = i_data[EXT3_TIND_BLOCK]; - if (nr) { - ext3_free_branches(handle, inode, NULL, &nr, &nr+1, 3); - i_data[EXT3_TIND_BLOCK] = 0; - } - case EXT3_TIND_BLOCK: - ; - } - - ext3_discard_reservation(inode); - - mutex_unlock(&ei->truncate_mutex); - inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC; - ext3_mark_inode_dirty(handle, inode); - - /* - * In a multi-transaction truncate, we only make the final transaction - * synchronous - */ - if (IS_SYNC(inode)) - handle->h_sync = 1; -out_stop: - /* - * If this was a simple ftruncate(), and the file will remain alive - * then we need to clear up the orphan record which we created above. - * However, if this was a real unlink then we were called by - * ext3_evict_inode(), and we allow that function to clean up the - * orphan info for us. - */ - if (inode->i_nlink) - ext3_orphan_del(handle, inode); - - ext3_journal_stop(handle); - trace_ext3_truncate_exit(inode); - return; -out_notrans: - /* - * Delete the inode from orphan list so that it doesn't stay there - * forever and trigger assertion on umount. - */ - if (inode->i_nlink) - ext3_orphan_del(NULL, inode); - trace_ext3_truncate_exit(inode); -} - -static ext3_fsblk_t ext3_get_inode_block(struct super_block *sb, - unsigned long ino, struct ext3_iloc *iloc) -{ - unsigned long block_group; - unsigned long offset; - ext3_fsblk_t block; - struct ext3_group_desc *gdp; - - if (!ext3_valid_inum(sb, ino)) { - /* - * This error is already checked for in namei.c unless we are - * looking at an NFS filehandle, in which case no error - * report is needed - */ - return 0; - } - - block_group = (ino - 1) / EXT3_INODES_PER_GROUP(sb); - gdp = ext3_get_group_desc(sb, block_group, NULL); - if (!gdp) - return 0; - /* - * Figure out the offset within the block group inode table - */ - offset = ((ino - 1) % EXT3_INODES_PER_GROUP(sb)) * - EXT3_INODE_SIZE(sb); - block = le32_to_cpu(gdp->bg_inode_table) + - (offset >> EXT3_BLOCK_SIZE_BITS(sb)); - - iloc->block_group = block_group; - iloc->offset = offset & (EXT3_BLOCK_SIZE(sb) - 1); - return block; -} - -/* - * ext3_get_inode_loc returns with an extra refcount against the inode's - * underlying buffer_head on success. If 'in_mem' is true, we have all - * data in memory that is needed to recreate the on-disk version of this - * inode. - */ -static int __ext3_get_inode_loc(struct inode *inode, - struct ext3_iloc *iloc, int in_mem) -{ - ext3_fsblk_t block; - struct buffer_head *bh; - - block = ext3_get_inode_block(inode->i_sb, inode->i_ino, iloc); - if (!block) - return -EIO; - - bh = sb_getblk(inode->i_sb, block); - if (unlikely(!bh)) { - ext3_error (inode->i_sb, "ext3_get_inode_loc", - "unable to read inode block - " - "inode=%lu, block="E3FSBLK, - inode->i_ino, block); - return -ENOMEM; - } - if (!buffer_uptodate(bh)) { - lock_buffer(bh); - - /* - * If the buffer has the write error flag, we have failed - * to write out another inode in the same block. In this - * case, we don't have to read the block because we may - * read the old inode data successfully. - */ - if (buffer_write_io_error(bh) && !buffer_uptodate(bh)) - set_buffer_uptodate(bh); - - if (buffer_uptodate(bh)) { - /* someone brought it uptodate while we waited */ - unlock_buffer(bh); - goto has_buffer; - } - - /* - * If we have all information of the inode in memory and this - * is the only valid inode in the block, we need not read the - * block. - */ - if (in_mem) { - struct buffer_head *bitmap_bh; - struct ext3_group_desc *desc; - int inodes_per_buffer; - int inode_offset, i; - int block_group; - int start; - - block_group = (inode->i_ino - 1) / - EXT3_INODES_PER_GROUP(inode->i_sb); - inodes_per_buffer = bh->b_size / - EXT3_INODE_SIZE(inode->i_sb); - inode_offset = ((inode->i_ino - 1) % - EXT3_INODES_PER_GROUP(inode->i_sb)); - start = inode_offset & ~(inodes_per_buffer - 1); - - /* Is the inode bitmap in cache? */ - desc = ext3_get_group_desc(inode->i_sb, - block_group, NULL); - if (!desc) - goto make_io; - - bitmap_bh = sb_getblk(inode->i_sb, - le32_to_cpu(desc->bg_inode_bitmap)); - if (unlikely(!bitmap_bh)) - goto make_io; - - /* - * If the inode bitmap isn't in cache then the - * optimisation may end up performing two reads instead - * of one, so skip it. - */ - if (!buffer_uptodate(bitmap_bh)) { - brelse(bitmap_bh); - goto make_io; - } - for (i = start; i < start + inodes_per_buffer; i++) { - if (i == inode_offset) - continue; - if (ext3_test_bit(i, bitmap_bh->b_data)) - break; - } - brelse(bitmap_bh); - if (i == start + inodes_per_buffer) { - /* all other inodes are free, so skip I/O */ - memset(bh->b_data, 0, bh->b_size); - set_buffer_uptodate(bh); - unlock_buffer(bh); - goto has_buffer; - } - } - -make_io: - /* - * There are other valid inodes in the buffer, this inode - * has in-inode xattrs, or we don't have this inode in memory. - * Read the block from disk. - */ - trace_ext3_load_inode(inode); - get_bh(bh); - bh->b_end_io = end_buffer_read_sync; - submit_bh(READ | REQ_META | REQ_PRIO, bh); - wait_on_buffer(bh); - if (!buffer_uptodate(bh)) { - ext3_error(inode->i_sb, "ext3_get_inode_loc", - "unable to read inode block - " - "inode=%lu, block="E3FSBLK, - inode->i_ino, block); - brelse(bh); - return -EIO; - } - } -has_buffer: - iloc->bh = bh; - return 0; -} - -int ext3_get_inode_loc(struct inode *inode, struct ext3_iloc *iloc) -{ - /* We have all inode data except xattrs in memory here. */ - return __ext3_get_inode_loc(inode, iloc, - !ext3_test_inode_state(inode, EXT3_STATE_XATTR)); -} - -void ext3_set_inode_flags(struct inode *inode) -{ - unsigned int flags = EXT3_I(inode)->i_flags; - - inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC); - if (flags & EXT3_SYNC_FL) - inode->i_flags |= S_SYNC; - if (flags & EXT3_APPEND_FL) - inode->i_flags |= S_APPEND; - if (flags & EXT3_IMMUTABLE_FL) - inode->i_flags |= S_IMMUTABLE; - if (flags & EXT3_NOATIME_FL) - inode->i_flags |= S_NOATIME; - if (flags & EXT3_DIRSYNC_FL) - inode->i_flags |= S_DIRSYNC; -} - -/* Propagate flags from i_flags to EXT3_I(inode)->i_flags */ -void ext3_get_inode_flags(struct ext3_inode_info *ei) -{ - unsigned int flags = ei->vfs_inode.i_flags; - - ei->i_flags &= ~(EXT3_SYNC_FL|EXT3_APPEND_FL| - EXT3_IMMUTABLE_FL|EXT3_NOATIME_FL|EXT3_DIRSYNC_FL); - if (flags & S_SYNC) - ei->i_flags |= EXT3_SYNC_FL; - if (flags & S_APPEND) - ei->i_flags |= EXT3_APPEND_FL; - if (flags & S_IMMUTABLE) - ei->i_flags |= EXT3_IMMUTABLE_FL; - if (flags & S_NOATIME) - ei->i_flags |= EXT3_NOATIME_FL; - if (flags & S_DIRSYNC) - ei->i_flags |= EXT3_DIRSYNC_FL; -} - -struct inode *ext3_iget(struct super_block *sb, unsigned long ino) -{ - struct ext3_iloc iloc; - struct ext3_inode *raw_inode; - struct ext3_inode_info *ei; - struct buffer_head *bh; - struct inode *inode; - journal_t *journal = EXT3_SB(sb)->s_journal; - transaction_t *transaction; - long ret; - int block; - uid_t i_uid; - gid_t i_gid; - - inode = iget_locked(sb, ino); - if (!inode) - return ERR_PTR(-ENOMEM); - if (!(inode->i_state & I_NEW)) - return inode; - - ei = EXT3_I(inode); - ei->i_block_alloc_info = NULL; - - ret = __ext3_get_inode_loc(inode, &iloc, 0); - if (ret < 0) - goto bad_inode; - bh = iloc.bh; - raw_inode = ext3_raw_inode(&iloc); - inode->i_mode = le16_to_cpu(raw_inode->i_mode); - i_uid = (uid_t)le16_to_cpu(raw_inode->i_uid_low); - i_gid = (gid_t)le16_to_cpu(raw_inode->i_gid_low); - if(!(test_opt (inode->i_sb, NO_UID32))) { - i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16; - i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16; - } - i_uid_write(inode, i_uid); - i_gid_write(inode, i_gid); - set_nlink(inode, le16_to_cpu(raw_inode->i_links_count)); - inode->i_size = le32_to_cpu(raw_inode->i_size); - inode->i_atime.tv_sec = (signed)le32_to_cpu(raw_inode->i_atime); - inode->i_ctime.tv_sec = (signed)le32_to_cpu(raw_inode->i_ctime); - inode->i_mtime.tv_sec = (signed)le32_to_cpu(raw_inode->i_mtime); - inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = inode->i_mtime.tv_nsec = 0; - - ei->i_state_flags = 0; - ei->i_dir_start_lookup = 0; - ei->i_dtime = le32_to_cpu(raw_inode->i_dtime); - /* We now have enough fields to check if the inode was active or not. - * This is needed because nfsd might try to access dead inodes - * the test is that same one that e2fsck uses - * NeilBrown 1999oct15 - */ - if (inode->i_nlink == 0) { - if (inode->i_mode == 0 || - !(EXT3_SB(inode->i_sb)->s_mount_state & EXT3_ORPHAN_FS)) { - /* this inode is deleted */ - brelse (bh); - ret = -ESTALE; - goto bad_inode; - } - /* The only unlinked inodes we let through here have - * valid i_mode and are being read by the orphan - * recovery code: that's fine, we're about to complete - * the process of deleting those. */ - } - inode->i_blocks = le32_to_cpu(raw_inode->i_blocks); - ei->i_flags = le32_to_cpu(raw_inode->i_flags); -#ifdef EXT3_FRAGMENTS - ei->i_faddr = le32_to_cpu(raw_inode->i_faddr); - ei->i_frag_no = raw_inode->i_frag; - ei->i_frag_size = raw_inode->i_fsize; -#endif - ei->i_file_acl = le32_to_cpu(raw_inode->i_file_acl); - if (!S_ISREG(inode->i_mode)) { - ei->i_dir_acl = le32_to_cpu(raw_inode->i_dir_acl); - } else { - inode->i_size |= - ((__u64)le32_to_cpu(raw_inode->i_size_high)) << 32; - } - ei->i_disksize = inode->i_size; - inode->i_generation = le32_to_cpu(raw_inode->i_generation); - ei->i_block_group = iloc.block_group; - /* - * NOTE! The in-memory inode i_data array is in little-endian order - * even on big-endian machines: we do NOT byteswap the block numbers! - */ - for (block = 0; block < EXT3_N_BLOCKS; block++) - ei->i_data[block] = raw_inode->i_block[block]; - INIT_LIST_HEAD(&ei->i_orphan); - - /* - * Set transaction id's of transactions that have to be committed - * to finish f[data]sync. We set them to currently running transaction - * as we cannot be sure that the inode or some of its metadata isn't - * part of the transaction - the inode could have been reclaimed and - * now it is reread from disk. - */ - if (journal) { - tid_t tid; - - spin_lock(&journal->j_state_lock); - if (journal->j_running_transaction) - transaction = journal->j_running_transaction; - else - transaction = journal->j_committing_transaction; - if (transaction) - tid = transaction->t_tid; - else - tid = journal->j_commit_sequence; - spin_unlock(&journal->j_state_lock); - atomic_set(&ei->i_sync_tid, tid); - atomic_set(&ei->i_datasync_tid, tid); - } - - if (inode->i_ino >= EXT3_FIRST_INO(inode->i_sb) + 1 && - EXT3_INODE_SIZE(inode->i_sb) > EXT3_GOOD_OLD_INODE_SIZE) { - /* - * When mke2fs creates big inodes it does not zero out - * the unused bytes above EXT3_GOOD_OLD_INODE_SIZE, - * so ignore those first few inodes. - */ - ei->i_extra_isize = le16_to_cpu(raw_inode->i_extra_isize); - if (EXT3_GOOD_OLD_INODE_SIZE + ei->i_extra_isize > - EXT3_INODE_SIZE(inode->i_sb)) { - brelse (bh); - ret = -EIO; - goto bad_inode; - } - if (ei->i_extra_isize == 0) { - /* The extra space is currently unused. Use it. */ - ei->i_extra_isize = sizeof(struct ext3_inode) - - EXT3_GOOD_OLD_INODE_SIZE; - } else { - __le32 *magic = (void *)raw_inode + - EXT3_GOOD_OLD_INODE_SIZE + - ei->i_extra_isize; - if (*magic == cpu_to_le32(EXT3_XATTR_MAGIC)) - ext3_set_inode_state(inode, EXT3_STATE_XATTR); - } - } else - ei->i_extra_isize = 0; - - if (S_ISREG(inode->i_mode)) { - inode->i_op = &ext3_file_inode_operations; - inode->i_fop = &ext3_file_operations; - ext3_set_aops(inode); - } else if (S_ISDIR(inode->i_mode)) { - inode->i_op = &ext3_dir_inode_operations; - inode->i_fop = &ext3_dir_operations; - } else if (S_ISLNK(inode->i_mode)) { - if (ext3_inode_is_fast_symlink(inode)) { - inode->i_op = &ext3_fast_symlink_inode_operations; - nd_terminate_link(ei->i_data, inode->i_size, - sizeof(ei->i_data) - 1); - inode->i_link = (char *)ei->i_data; - } else { - inode->i_op = &ext3_symlink_inode_operations; - ext3_set_aops(inode); - } - } else { - inode->i_op = &ext3_special_inode_operations; - if (raw_inode->i_block[0]) - init_special_inode(inode, inode->i_mode, - old_decode_dev(le32_to_cpu(raw_inode->i_block[0]))); - else - init_special_inode(inode, inode->i_mode, - new_decode_dev(le32_to_cpu(raw_inode->i_block[1]))); - } - brelse (iloc.bh); - ext3_set_inode_flags(inode); - unlock_new_inode(inode); - return inode; - -bad_inode: - iget_failed(inode); - return ERR_PTR(ret); -} - -/* - * Post the struct inode info into an on-disk inode location in the - * buffer-cache. This gobbles the caller's reference to the - * buffer_head in the inode location struct. - * - * The caller must have write access to iloc->bh. - */ -static int ext3_do_update_inode(handle_t *handle, - struct inode *inode, - struct ext3_iloc *iloc) -{ - struct ext3_inode *raw_inode = ext3_raw_inode(iloc); - struct ext3_inode_info *ei = EXT3_I(inode); - struct buffer_head *bh = iloc->bh; - int err = 0, rc, block; - int need_datasync = 0; - __le32 disksize; - uid_t i_uid; - gid_t i_gid; - -again: - /* we can't allow multiple procs in here at once, its a bit racey */ - lock_buffer(bh); - - /* For fields not not tracking in the in-memory inode, - * initialise them to zero for new inodes. */ - if (ext3_test_inode_state(inode, EXT3_STATE_NEW)) - memset(raw_inode, 0, EXT3_SB(inode->i_sb)->s_inode_size); - - ext3_get_inode_flags(ei); - raw_inode->i_mode = cpu_to_le16(inode->i_mode); - i_uid = i_uid_read(inode); - i_gid = i_gid_read(inode); - if(!(test_opt(inode->i_sb, NO_UID32))) { - raw_inode->i_uid_low = cpu_to_le16(low_16_bits(i_uid)); - raw_inode->i_gid_low = cpu_to_le16(low_16_bits(i_gid)); -/* - * Fix up interoperability with old kernels. Otherwise, old inodes get - * re-used with the upper 16 bits of the uid/gid intact - */ - if(!ei->i_dtime) { - raw_inode->i_uid_high = - cpu_to_le16(high_16_bits(i_uid)); - raw_inode->i_gid_high = - cpu_to_le16(high_16_bits(i_gid)); - } else { - raw_inode->i_uid_high = 0; - raw_inode->i_gid_high = 0; - } - } else { - raw_inode->i_uid_low = - cpu_to_le16(fs_high2lowuid(i_uid)); - raw_inode->i_gid_low = - cpu_to_le16(fs_high2lowgid(i_gid)); - raw_inode->i_uid_high = 0; - raw_inode->i_gid_high = 0; - } - raw_inode->i_links_count = cpu_to_le16(inode->i_nlink); - disksize = cpu_to_le32(ei->i_disksize); - if (disksize != raw_inode->i_size) { - need_datasync = 1; - raw_inode->i_size = disksize; - } - raw_inode->i_atime = cpu_to_le32(inode->i_atime.tv_sec); - raw_inode->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec); - raw_inode->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec); - raw_inode->i_blocks = cpu_to_le32(inode->i_blocks); - raw_inode->i_dtime = cpu_to_le32(ei->i_dtime); - raw_inode->i_flags = cpu_to_le32(ei->i_flags); -#ifdef EXT3_FRAGMENTS - raw_inode->i_faddr = cpu_to_le32(ei->i_faddr); - raw_inode->i_frag = ei->i_frag_no; - raw_inode->i_fsize = ei->i_frag_size; -#endif - raw_inode->i_file_acl = cpu_to_le32(ei->i_file_acl); - if (!S_ISREG(inode->i_mode)) { - raw_inode->i_dir_acl = cpu_to_le32(ei->i_dir_acl); - } else { - disksize = cpu_to_le32(ei->i_disksize >> 32); - if (disksize != raw_inode->i_size_high) { - raw_inode->i_size_high = disksize; - need_datasync = 1; - } - if (ei->i_disksize > 0x7fffffffULL) { - struct super_block *sb = inode->i_sb; - if (!EXT3_HAS_RO_COMPAT_FEATURE(sb, - EXT3_FEATURE_RO_COMPAT_LARGE_FILE) || - EXT3_SB(sb)->s_es->s_rev_level == - cpu_to_le32(EXT3_GOOD_OLD_REV)) { - /* If this is the first large file - * created, add a flag to the superblock. - */ - unlock_buffer(bh); - err = ext3_journal_get_write_access(handle, - EXT3_SB(sb)->s_sbh); - if (err) - goto out_brelse; - - ext3_update_dynamic_rev(sb); - EXT3_SET_RO_COMPAT_FEATURE(sb, - EXT3_FEATURE_RO_COMPAT_LARGE_FILE); - handle->h_sync = 1; - err = ext3_journal_dirty_metadata(handle, - EXT3_SB(sb)->s_sbh); - /* get our lock and start over */ - goto again; - } - } - } - raw_inode->i_generation = cpu_to_le32(inode->i_generation); - if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) { - if (old_valid_dev(inode->i_rdev)) { - raw_inode->i_block[0] = - cpu_to_le32(old_encode_dev(inode->i_rdev)); - raw_inode->i_block[1] = 0; - } else { - raw_inode->i_block[0] = 0; - raw_inode->i_block[1] = - cpu_to_le32(new_encode_dev(inode->i_rdev)); - raw_inode->i_block[2] = 0; - } - } else for (block = 0; block < EXT3_N_BLOCKS; block++) - raw_inode->i_block[block] = ei->i_data[block]; - - if (ei->i_extra_isize) - raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize); - - BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); - unlock_buffer(bh); - rc = ext3_journal_dirty_metadata(handle, bh); - if (!err) - err = rc; - ext3_clear_inode_state(inode, EXT3_STATE_NEW); - - atomic_set(&ei->i_sync_tid, handle->h_transaction->t_tid); - if (need_datasync) - atomic_set(&ei->i_datasync_tid, handle->h_transaction->t_tid); -out_brelse: - brelse (bh); - ext3_std_error(inode->i_sb, err); - return err; -} - -/* - * ext3_write_inode() - * - * We are called from a few places: - * - * - Within generic_file_aio_write() -> generic_write_sync() for O_SYNC files. - * Here, there will be no transaction running. We wait for any running - * transaction to commit. - * - * - Within flush work (for sys_sync(), kupdate and such). - * We wait on commit, if told to. - * - * - Within iput_final() -> write_inode_now() - * We wait on commit, if told to. - * - * In all cases it is actually safe for us to return without doing anything, - * because the inode has been copied into a raw inode buffer in - * ext3_mark_inode_dirty(). This is a correctness thing for WB_SYNC_ALL - * writeback. - * - * Note that we are absolutely dependent upon all inode dirtiers doing the - * right thing: they *must* call mark_inode_dirty() after dirtying info in - * which we are interested. - * - * It would be a bug for them to not do this. The code: - * - * mark_inode_dirty(inode) - * stuff(); - * inode->i_size = expr; - * - * is in error because write_inode() could occur while `stuff()' is running, - * and the new i_size will be lost. Plus the inode will no longer be on the - * superblock's dirty inode list. - */ -int ext3_write_inode(struct inode *inode, struct writeback_control *wbc) -{ - if (WARN_ON_ONCE(current->flags & PF_MEMALLOC)) - return 0; - - if (ext3_journal_current_handle()) { - jbd_debug(1, "called recursively, non-PF_MEMALLOC!\n"); - dump_stack(); - return -EIO; - } - - /* - * No need to force transaction in WB_SYNC_NONE mode. Also - * ext3_sync_fs() will force the commit after everything is - * written. - */ - if (wbc->sync_mode != WB_SYNC_ALL || wbc->for_sync) - return 0; - - return ext3_force_commit(inode->i_sb); -} - -/* - * ext3_setattr() - * - * Called from notify_change. - * - * We want to trap VFS attempts to truncate the file as soon as - * possible. In particular, we want to make sure that when the VFS - * shrinks i_size, we put the inode on the orphan list and modify - * i_disksize immediately, so that during the subsequent flushing of - * dirty pages and freeing of disk blocks, we can guarantee that any - * commit will leave the blocks being flushed in an unused state on - * disk. (On recovery, the inode will get truncated and the blocks will - * be freed, so we have a strong guarantee that no future commit will - * leave these blocks visible to the user.) - * - * Called with inode->sem down. - */ -int ext3_setattr(struct dentry *dentry, struct iattr *attr) -{ - struct inode *inode = d_inode(dentry); - int error, rc = 0; - const unsigned int ia_valid = attr->ia_valid; - - error = inode_change_ok(inode, attr); - if (error) - return error; - - if (is_quota_modification(inode, attr)) - dquot_initialize(inode); - if ((ia_valid & ATTR_UID && !uid_eq(attr->ia_uid, inode->i_uid)) || - (ia_valid & ATTR_GID && !gid_eq(attr->ia_gid, inode->i_gid))) { - handle_t *handle; - - /* (user+group)*(old+new) structure, inode write (sb, - * inode block, ? - but truncate inode update has it) */ - handle = ext3_journal_start(inode, EXT3_MAXQUOTAS_INIT_BLOCKS(inode->i_sb)+ - EXT3_MAXQUOTAS_DEL_BLOCKS(inode->i_sb)+3); - if (IS_ERR(handle)) { - error = PTR_ERR(handle); - goto err_out; - } - error = dquot_transfer(inode, attr); - if (error) { - ext3_journal_stop(handle); - return error; - } - /* Update corresponding info in inode so that everything is in - * one transaction */ - if (attr->ia_valid & ATTR_UID) - inode->i_uid = attr->ia_uid; - if (attr->ia_valid & ATTR_GID) - inode->i_gid = attr->ia_gid; - error = ext3_mark_inode_dirty(handle, inode); - ext3_journal_stop(handle); - } - - if (attr->ia_valid & ATTR_SIZE) - inode_dio_wait(inode); - - if (S_ISREG(inode->i_mode) && - attr->ia_valid & ATTR_SIZE && attr->ia_size < inode->i_size) { - handle_t *handle; - - handle = ext3_journal_start(inode, 3); - if (IS_ERR(handle)) { - error = PTR_ERR(handle); - goto err_out; - } - - error = ext3_orphan_add(handle, inode); - if (error) { - ext3_journal_stop(handle); - goto err_out; - } - EXT3_I(inode)->i_disksize = attr->ia_size; - error = ext3_mark_inode_dirty(handle, inode); - ext3_journal_stop(handle); - if (error) { - /* Some hard fs error must have happened. Bail out. */ - ext3_orphan_del(NULL, inode); - goto err_out; - } - rc = ext3_block_truncate_page(inode, attr->ia_size); - if (rc) { - /* Cleanup orphan list and exit */ - handle = ext3_journal_start(inode, 3); - if (IS_ERR(handle)) { - ext3_orphan_del(NULL, inode); - goto err_out; - } - ext3_orphan_del(handle, inode); - ext3_journal_stop(handle); - goto err_out; - } - } - - if ((attr->ia_valid & ATTR_SIZE) && - attr->ia_size != i_size_read(inode)) { - truncate_setsize(inode, attr->ia_size); - ext3_truncate(inode); - } - - setattr_copy(inode, attr); - mark_inode_dirty(inode); - - if (ia_valid & ATTR_MODE) - rc = posix_acl_chmod(inode, inode->i_mode); - -err_out: - ext3_std_error(inode->i_sb, error); - if (!error) - error = rc; - return error; -} - - -/* - * How many blocks doth make a writepage()? - * - * With N blocks per page, it may be: - * N data blocks - * 2 indirect block - * 2 dindirect - * 1 tindirect - * N+5 bitmap blocks (from the above) - * N+5 group descriptor summary blocks - * 1 inode block - * 1 superblock. - * 2 * EXT3_SINGLEDATA_TRANS_BLOCKS for the quote files - * - * 3 * (N + 5) + 2 + 2 * EXT3_SINGLEDATA_TRANS_BLOCKS - * - * With ordered or writeback data it's the same, less the N data blocks. - * - * If the inode's direct blocks can hold an integral number of pages then a - * page cannot straddle two indirect blocks, and we can only touch one indirect - * and dindirect block, and the "5" above becomes "3". - * - * This still overestimates under most circumstances. If we were to pass the - * start and end offsets in here as well we could do block_to_path() on each - * block and work out the exact number of indirects which are touched. Pah. - */ - -static int ext3_writepage_trans_blocks(struct inode *inode) -{ - int bpp = ext3_journal_blocks_per_page(inode); - int indirects = (EXT3_NDIR_BLOCKS % bpp) ? 5 : 3; - int ret; - - if (ext3_should_journal_data(inode)) - ret = 3 * (bpp + indirects) + 2; - else - ret = 2 * (bpp + indirects) + indirects + 2; - -#ifdef CONFIG_QUOTA - /* We know that structure was already allocated during dquot_initialize so - * we will be updating only the data blocks + inodes */ - ret += EXT3_MAXQUOTAS_TRANS_BLOCKS(inode->i_sb); -#endif - - return ret; -} - -/* - * The caller must have previously called ext3_reserve_inode_write(). - * Give this, we know that the caller already has write access to iloc->bh. - */ -int ext3_mark_iloc_dirty(handle_t *handle, - struct inode *inode, struct ext3_iloc *iloc) -{ - int err = 0; - - /* the do_update_inode consumes one bh->b_count */ - get_bh(iloc->bh); - - /* ext3_do_update_inode() does journal_dirty_metadata */ - err = ext3_do_update_inode(handle, inode, iloc); - put_bh(iloc->bh); - return err; -} - -/* - * On success, We end up with an outstanding reference count against - * iloc->bh. This _must_ be cleaned up later. - */ - -int -ext3_reserve_inode_write(handle_t *handle, struct inode *inode, - struct ext3_iloc *iloc) -{ - int err = 0; - if (handle) { - err = ext3_get_inode_loc(inode, iloc); - if (!err) { - BUFFER_TRACE(iloc->bh, "get_write_access"); - err = ext3_journal_get_write_access(handle, iloc->bh); - if (err) { - brelse(iloc->bh); - iloc->bh = NULL; - } - } - } - ext3_std_error(inode->i_sb, err); - return err; -} - -/* - * What we do here is to mark the in-core inode as clean with respect to inode - * dirtiness (it may still be data-dirty). - * This means that the in-core inode may be reaped by prune_icache - * without having to perform any I/O. This is a very good thing, - * because *any* task may call prune_icache - even ones which - * have a transaction open against a different journal. - * - * Is this cheating? Not really. Sure, we haven't written the - * inode out, but prune_icache isn't a user-visible syncing function. - * Whenever the user wants stuff synced (sys_sync, sys_msync, sys_fsync) - * we start and wait on commits. - */ -int ext3_mark_inode_dirty(handle_t *handle, struct inode *inode) -{ - struct ext3_iloc iloc; - int err; - - might_sleep(); - trace_ext3_mark_inode_dirty(inode, _RET_IP_); - err = ext3_reserve_inode_write(handle, inode, &iloc); - if (!err) - err = ext3_mark_iloc_dirty(handle, inode, &iloc); - return err; -} - -/* - * ext3_dirty_inode() is called from __mark_inode_dirty() - * - * We're really interested in the case where a file is being extended. - * i_size has been changed by generic_commit_write() and we thus need - * to include the updated inode in the current transaction. - * - * Also, dquot_alloc_space() will always dirty the inode when blocks - * are allocated to the file. - * - * If the inode is marked synchronous, we don't honour that here - doing - * so would cause a commit on atime updates, which we don't bother doing. - * We handle synchronous inodes at the highest possible level. - */ -void ext3_dirty_inode(struct inode *inode, int flags) -{ - handle_t *current_handle = ext3_journal_current_handle(); - handle_t *handle; - - handle = ext3_journal_start(inode, 2); - if (IS_ERR(handle)) - goto out; - if (current_handle && - current_handle->h_transaction != handle->h_transaction) { - /* This task has a transaction open against a different fs */ - printk(KERN_EMERG "%s: transactions do not match!\n", - __func__); - } else { - jbd_debug(5, "marking dirty. outer handle=%p\n", - current_handle); - ext3_mark_inode_dirty(handle, inode); - } - ext3_journal_stop(handle); -out: - return; -} - -#if 0 -/* - * Bind an inode's backing buffer_head into this transaction, to prevent - * it from being flushed to disk early. Unlike - * ext3_reserve_inode_write, this leaves behind no bh reference and - * returns no iloc structure, so the caller needs to repeat the iloc - * lookup to mark the inode dirty later. - */ -static int ext3_pin_inode(handle_t *handle, struct inode *inode) -{ - struct ext3_iloc iloc; - - int err = 0; - if (handle) { - err = ext3_get_inode_loc(inode, &iloc); - if (!err) { - BUFFER_TRACE(iloc.bh, "get_write_access"); - err = journal_get_write_access(handle, iloc.bh); - if (!err) - err = ext3_journal_dirty_metadata(handle, - iloc.bh); - brelse(iloc.bh); - } - } - ext3_std_error(inode->i_sb, err); - return err; -} -#endif - -int ext3_change_inode_journal_flag(struct inode *inode, int val) -{ - journal_t *journal; - handle_t *handle; - int err; - - /* - * We have to be very careful here: changing a data block's - * journaling status dynamically is dangerous. If we write a - * data block to the journal, change the status and then delete - * that block, we risk forgetting to revoke the old log record - * from the journal and so a subsequent replay can corrupt data. - * So, first we make sure that the journal is empty and that - * nobody is changing anything. - */ - - journal = EXT3_JOURNAL(inode); - if (is_journal_aborted(journal)) - return -EROFS; - - journal_lock_updates(journal); - journal_flush(journal); - - /* - * OK, there are no updates running now, and all cached data is - * synced to disk. We are now in a completely consistent state - * which doesn't have anything in the journal, and we know that - * no filesystem updates are running, so it is safe to modify - * the inode's in-core data-journaling state flag now. - */ - - if (val) - EXT3_I(inode)->i_flags |= EXT3_JOURNAL_DATA_FL; - else - EXT3_I(inode)->i_flags &= ~EXT3_JOURNAL_DATA_FL; - ext3_set_aops(inode); - - journal_unlock_updates(journal); - - /* Finally we can mark the inode as dirty. */ - - handle = ext3_journal_start(inode, 1); - if (IS_ERR(handle)) - return PTR_ERR(handle); - - err = ext3_mark_inode_dirty(handle, inode); - handle->h_sync = 1; - ext3_journal_stop(handle); - ext3_std_error(inode->i_sb, err); - - return err; -} |