diff options
Diffstat (limited to 'fs/ocfs2/localalloc.c')
| -rw-r--r-- | fs/ocfs2/localalloc.c | 1343 |
1 files changed, 1343 insertions, 0 deletions
diff --git a/fs/ocfs2/localalloc.c b/fs/ocfs2/localalloc.c new file mode 100644 index 000000000..857bbbcd3 --- /dev/null +++ b/fs/ocfs2/localalloc.c @@ -0,0 +1,1343 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * localalloc.c + * + * Node local data allocation + * + * Copyright (C) 2002, 2004 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ + +#include <linux/fs.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/highmem.h> +#include <linux/bitops.h> + +#include <cluster/masklog.h> + +#include "ocfs2.h" + +#include "alloc.h" +#include "blockcheck.h" +#include "dlmglue.h" +#include "inode.h" +#include "journal.h" +#include "localalloc.h" +#include "suballoc.h" +#include "super.h" +#include "sysfile.h" +#include "ocfs2_trace.h" + +#include "buffer_head_io.h" + +#define OCFS2_LOCAL_ALLOC(dinode) (&((dinode)->id2.i_lab)) + +static u32 ocfs2_local_alloc_count_bits(struct ocfs2_dinode *alloc); + +static int ocfs2_local_alloc_find_clear_bits(struct ocfs2_super *osb, + struct ocfs2_dinode *alloc, + u32 *numbits, + struct ocfs2_alloc_reservation *resv); + +static void ocfs2_clear_local_alloc(struct ocfs2_dinode *alloc); + +static int ocfs2_sync_local_to_main(struct ocfs2_super *osb, + handle_t *handle, + struct ocfs2_dinode *alloc, + struct inode *main_bm_inode, + struct buffer_head *main_bm_bh); + +static int ocfs2_local_alloc_reserve_for_window(struct ocfs2_super *osb, + struct ocfs2_alloc_context **ac, + struct inode **bitmap_inode, + struct buffer_head **bitmap_bh); + +static int ocfs2_local_alloc_new_window(struct ocfs2_super *osb, + handle_t *handle, + struct ocfs2_alloc_context *ac); + +static int ocfs2_local_alloc_slide_window(struct ocfs2_super *osb, + struct inode *local_alloc_inode); + +/* + * ocfs2_la_default_mb() - determine a default size, in megabytes of + * the local alloc. + * + * Generally, we'd like to pick as large a local alloc as + * possible. Performance on large workloads tends to scale + * proportionally to la size. In addition to that, the reservations + * code functions more efficiently as it can reserve more windows for + * write. + * + * Some things work against us when trying to choose a large local alloc: + * + * - We need to ensure our sizing is picked to leave enough space in + * group descriptors for other allocations (such as block groups, + * etc). Picking default sizes which are a multiple of 4 could help + * - block groups are allocated in 2mb and 4mb chunks. + * + * - Likewise, we don't want to starve other nodes of bits on small + * file systems. This can easily be taken care of by limiting our + * default to a reasonable size (256M) on larger cluster sizes. + * + * - Some file systems can't support very large sizes - 4k and 8k in + * particular are limited to less than 128 and 256 megabytes respectively. + * + * The following reference table shows group descriptor and local + * alloc maximums at various cluster sizes (4k blocksize) + * + * csize: 4K group: 126M la: 121M + * csize: 8K group: 252M la: 243M + * csize: 16K group: 504M la: 486M + * csize: 32K group: 1008M la: 972M + * csize: 64K group: 2016M la: 1944M + * csize: 128K group: 4032M la: 3888M + * csize: 256K group: 8064M la: 7776M + * csize: 512K group: 16128M la: 15552M + * csize: 1024K group: 32256M la: 31104M + */ +#define OCFS2_LA_MAX_DEFAULT_MB 256 +#define OCFS2_LA_OLD_DEFAULT 8 +unsigned int ocfs2_la_default_mb(struct ocfs2_super *osb) +{ + unsigned int la_mb; + unsigned int gd_mb; + unsigned int la_max_mb; + unsigned int megs_per_slot; + struct super_block *sb = osb->sb; + + gd_mb = ocfs2_clusters_to_megabytes(osb->sb, + 8 * ocfs2_group_bitmap_size(sb, 0, osb->s_feature_incompat)); + + /* + * This takes care of files systems with very small group + * descriptors - 512 byte blocksize at cluster sizes lower + * than 16K and also 1k blocksize with 4k cluster size. + */ + if ((sb->s_blocksize == 512 && osb->s_clustersize <= 8192) + || (sb->s_blocksize == 1024 && osb->s_clustersize == 4096)) + return OCFS2_LA_OLD_DEFAULT; + + /* + * Leave enough room for some block groups and make the final + * value we work from a multiple of 4. + */ + gd_mb -= 16; + gd_mb &= 0xFFFFFFFB; + + la_mb = gd_mb; + + /* + * Keep window sizes down to a reasonable default + */ + if (la_mb > OCFS2_LA_MAX_DEFAULT_MB) { + /* + * Some clustersize / blocksize combinations will have + * given us a larger than OCFS2_LA_MAX_DEFAULT_MB + * default size, but get poor distribution when + * limited to exactly 256 megabytes. + * + * As an example, 16K clustersize at 4K blocksize + * gives us a cluster group size of 504M. Paring the + * local alloc size down to 256 however, would give us + * only one window and around 200MB left in the + * cluster group. Instead, find the first size below + * 256 which would give us an even distribution. + * + * Larger cluster group sizes actually work out pretty + * well when pared to 256, so we don't have to do this + * for any group that fits more than two + * OCFS2_LA_MAX_DEFAULT_MB windows. + */ + if (gd_mb > (2 * OCFS2_LA_MAX_DEFAULT_MB)) + la_mb = 256; + else { + unsigned int gd_mult = gd_mb; + + while (gd_mult > 256) + gd_mult = gd_mult >> 1; + + la_mb = gd_mult; + } + } + + megs_per_slot = osb->osb_clusters_at_boot / osb->max_slots; + megs_per_slot = ocfs2_clusters_to_megabytes(osb->sb, megs_per_slot); + /* Too many nodes, too few disk clusters. */ + if (megs_per_slot < la_mb) + la_mb = megs_per_slot; + + /* We can't store more bits than we can in a block. */ + la_max_mb = ocfs2_clusters_to_megabytes(osb->sb, + ocfs2_local_alloc_size(sb) * 8); + if (la_mb > la_max_mb) + la_mb = la_max_mb; + + return la_mb; +} + +void ocfs2_la_set_sizes(struct ocfs2_super *osb, int requested_mb) +{ + struct super_block *sb = osb->sb; + unsigned int la_default_mb = ocfs2_la_default_mb(osb); + unsigned int la_max_mb; + + la_max_mb = ocfs2_clusters_to_megabytes(sb, + ocfs2_local_alloc_size(sb) * 8); + + trace_ocfs2_la_set_sizes(requested_mb, la_max_mb, la_default_mb); + + if (requested_mb == -1) { + /* No user request - use defaults */ + osb->local_alloc_default_bits = + ocfs2_megabytes_to_clusters(sb, la_default_mb); + } else if (requested_mb > la_max_mb) { + /* Request is too big, we give the maximum available */ + osb->local_alloc_default_bits = + ocfs2_megabytes_to_clusters(sb, la_max_mb); + } else { + osb->local_alloc_default_bits = + ocfs2_megabytes_to_clusters(sb, requested_mb); + } + + osb->local_alloc_bits = osb->local_alloc_default_bits; +} + +static inline int ocfs2_la_state_enabled(struct ocfs2_super *osb) +{ + return (osb->local_alloc_state == OCFS2_LA_THROTTLED || + osb->local_alloc_state == OCFS2_LA_ENABLED); +} + +void ocfs2_local_alloc_seen_free_bits(struct ocfs2_super *osb, + unsigned int num_clusters) +{ + spin_lock(&osb->osb_lock); + if (osb->local_alloc_state == OCFS2_LA_DISABLED || + osb->local_alloc_state == OCFS2_LA_THROTTLED) + if (num_clusters >= osb->local_alloc_default_bits) { + cancel_delayed_work(&osb->la_enable_wq); + osb->local_alloc_state = OCFS2_LA_ENABLED; + } + spin_unlock(&osb->osb_lock); +} + +void ocfs2_la_enable_worker(struct work_struct *work) +{ + struct ocfs2_super *osb = + container_of(work, struct ocfs2_super, + la_enable_wq.work); + spin_lock(&osb->osb_lock); + osb->local_alloc_state = OCFS2_LA_ENABLED; + spin_unlock(&osb->osb_lock); +} + +/* + * Tell us whether a given allocation should use the local alloc + * file. Otherwise, it has to go to the main bitmap. + * + * This function does semi-dirty reads of local alloc size and state! + * This is ok however, as the values are re-checked once under mutex. + */ +int ocfs2_alloc_should_use_local(struct ocfs2_super *osb, u64 bits) +{ + int ret = 0; + int la_bits; + + spin_lock(&osb->osb_lock); + la_bits = osb->local_alloc_bits; + + if (!ocfs2_la_state_enabled(osb)) + goto bail; + + /* la_bits should be at least twice the size (in clusters) of + * a new block group. We want to be sure block group + * allocations go through the local alloc, so allow an + * allocation to take up to half the bitmap. */ + if (bits > (la_bits / 2)) + goto bail; + + ret = 1; +bail: + trace_ocfs2_alloc_should_use_local( + (unsigned long long)bits, osb->local_alloc_state, la_bits, ret); + spin_unlock(&osb->osb_lock); + return ret; +} + +int ocfs2_load_local_alloc(struct ocfs2_super *osb) +{ + int status = 0; + struct ocfs2_dinode *alloc = NULL; + struct buffer_head *alloc_bh = NULL; + u32 num_used; + struct inode *inode = NULL; + struct ocfs2_local_alloc *la; + + if (osb->local_alloc_bits == 0) + goto bail; + + if (osb->local_alloc_bits >= osb->bitmap_cpg) { + mlog(ML_NOTICE, "Requested local alloc window %d is larger " + "than max possible %u. Using defaults.\n", + osb->local_alloc_bits, (osb->bitmap_cpg - 1)); + osb->local_alloc_bits = + ocfs2_megabytes_to_clusters(osb->sb, + ocfs2_la_default_mb(osb)); + } + + /* read the alloc off disk */ + inode = ocfs2_get_system_file_inode(osb, LOCAL_ALLOC_SYSTEM_INODE, + osb->slot_num); + if (!inode) { + status = -EINVAL; + mlog_errno(status); + goto bail; + } + + status = ocfs2_read_inode_block_full(inode, &alloc_bh, + OCFS2_BH_IGNORE_CACHE); + if (status < 0) { + mlog_errno(status); + goto bail; + } + + alloc = (struct ocfs2_dinode *) alloc_bh->b_data; + la = OCFS2_LOCAL_ALLOC(alloc); + + if (!(le32_to_cpu(alloc->i_flags) & + (OCFS2_LOCAL_ALLOC_FL|OCFS2_BITMAP_FL))) { + mlog(ML_ERROR, "Invalid local alloc inode, %llu\n", + (unsigned long long)OCFS2_I(inode)->ip_blkno); + status = -EINVAL; + goto bail; + } + + if ((la->la_size == 0) || + (le16_to_cpu(la->la_size) > ocfs2_local_alloc_size(inode->i_sb))) { + mlog(ML_ERROR, "Local alloc size is invalid (la_size = %u)\n", + le16_to_cpu(la->la_size)); + status = -EINVAL; + goto bail; + } + + /* do a little verification. */ + num_used = ocfs2_local_alloc_count_bits(alloc); + + /* hopefully the local alloc has always been recovered before + * we load it. */ + if (num_used + || alloc->id1.bitmap1.i_used + || alloc->id1.bitmap1.i_total + || la->la_bm_off) + mlog(ML_ERROR, "Local alloc hasn't been recovered!\n" + "found = %u, set = %u, taken = %u, off = %u\n", + num_used, le32_to_cpu(alloc->id1.bitmap1.i_used), + le32_to_cpu(alloc->id1.bitmap1.i_total), + OCFS2_LOCAL_ALLOC(alloc)->la_bm_off); + + osb->local_alloc_bh = alloc_bh; + osb->local_alloc_state = OCFS2_LA_ENABLED; + +bail: + if (status < 0) + brelse(alloc_bh); + if (inode) + iput(inode); + + trace_ocfs2_load_local_alloc(osb->local_alloc_bits); + + if (status) + mlog_errno(status); + return status; +} + +/* + * return any unused bits to the bitmap and write out a clean + * local_alloc. + * + * local_alloc_bh is optional. If not passed, we will simply use the + * one off osb. If you do pass it however, be warned that it *will* be + * returned brelse'd and NULL'd out.*/ +void ocfs2_shutdown_local_alloc(struct ocfs2_super *osb) +{ + int status; + handle_t *handle; + struct inode *local_alloc_inode = NULL; + struct buffer_head *bh = NULL; + struct buffer_head *main_bm_bh = NULL; + struct inode *main_bm_inode = NULL; + struct ocfs2_dinode *alloc_copy = NULL; + struct ocfs2_dinode *alloc = NULL; + + cancel_delayed_work(&osb->la_enable_wq); + flush_workqueue(ocfs2_wq); + + if (osb->local_alloc_state == OCFS2_LA_UNUSED) + goto out; + + local_alloc_inode = + ocfs2_get_system_file_inode(osb, + LOCAL_ALLOC_SYSTEM_INODE, + osb->slot_num); + if (!local_alloc_inode) { + status = -ENOENT; + mlog_errno(status); + goto out; + } + + osb->local_alloc_state = OCFS2_LA_DISABLED; + + ocfs2_resmap_uninit(&osb->osb_la_resmap); + + main_bm_inode = ocfs2_get_system_file_inode(osb, + GLOBAL_BITMAP_SYSTEM_INODE, + OCFS2_INVALID_SLOT); + if (!main_bm_inode) { + status = -EINVAL; + mlog_errno(status); + goto out; + } + + mutex_lock(&main_bm_inode->i_mutex); + + status = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 1); + if (status < 0) { + mlog_errno(status); + goto out_mutex; + } + + /* WINDOW_MOVE_CREDITS is a bit heavy... */ + handle = ocfs2_start_trans(osb, OCFS2_WINDOW_MOVE_CREDITS); + if (IS_ERR(handle)) { + mlog_errno(PTR_ERR(handle)); + handle = NULL; + goto out_unlock; + } + + bh = osb->local_alloc_bh; + alloc = (struct ocfs2_dinode *) bh->b_data; + + alloc_copy = kmalloc(bh->b_size, GFP_NOFS); + if (!alloc_copy) { + status = -ENOMEM; + goto out_commit; + } + memcpy(alloc_copy, alloc, bh->b_size); + + status = ocfs2_journal_access_di(handle, INODE_CACHE(local_alloc_inode), + bh, OCFS2_JOURNAL_ACCESS_WRITE); + if (status < 0) { + mlog_errno(status); + goto out_commit; + } + + ocfs2_clear_local_alloc(alloc); + ocfs2_journal_dirty(handle, bh); + + brelse(bh); + osb->local_alloc_bh = NULL; + osb->local_alloc_state = OCFS2_LA_UNUSED; + + status = ocfs2_sync_local_to_main(osb, handle, alloc_copy, + main_bm_inode, main_bm_bh); + if (status < 0) + mlog_errno(status); + +out_commit: + ocfs2_commit_trans(osb, handle); + +out_unlock: + brelse(main_bm_bh); + + ocfs2_inode_unlock(main_bm_inode, 1); + +out_mutex: + mutex_unlock(&main_bm_inode->i_mutex); + iput(main_bm_inode); + +out: + if (local_alloc_inode) + iput(local_alloc_inode); + + kfree(alloc_copy); +} + +/* + * We want to free the bitmap bits outside of any recovery context as + * we'll need a cluster lock to do so, but we must clear the local + * alloc before giving up the recovered nodes journal. To solve this, + * we kmalloc a copy of the local alloc before it's change for the + * caller to process with ocfs2_complete_local_alloc_recovery + */ +int ocfs2_begin_local_alloc_recovery(struct ocfs2_super *osb, + int slot_num, + struct ocfs2_dinode **alloc_copy) +{ + int status = 0; + struct buffer_head *alloc_bh = NULL; + struct inode *inode = NULL; + struct ocfs2_dinode *alloc; + + trace_ocfs2_begin_local_alloc_recovery(slot_num); + + *alloc_copy = NULL; + + inode = ocfs2_get_system_file_inode(osb, + LOCAL_ALLOC_SYSTEM_INODE, + slot_num); + if (!inode) { + status = -EINVAL; + mlog_errno(status); + goto bail; + } + + mutex_lock(&inode->i_mutex); + + status = ocfs2_read_inode_block_full(inode, &alloc_bh, + OCFS2_BH_IGNORE_CACHE); + if (status < 0) { + mlog_errno(status); + goto bail; + } + + *alloc_copy = kmalloc(alloc_bh->b_size, GFP_KERNEL); + if (!(*alloc_copy)) { + status = -ENOMEM; + goto bail; + } + memcpy((*alloc_copy), alloc_bh->b_data, alloc_bh->b_size); + + alloc = (struct ocfs2_dinode *) alloc_bh->b_data; + ocfs2_clear_local_alloc(alloc); + + ocfs2_compute_meta_ecc(osb->sb, alloc_bh->b_data, &alloc->i_check); + status = ocfs2_write_block(osb, alloc_bh, INODE_CACHE(inode)); + if (status < 0) + mlog_errno(status); + +bail: + if (status < 0) { + kfree(*alloc_copy); + *alloc_copy = NULL; + } + + brelse(alloc_bh); + + if (inode) { + mutex_unlock(&inode->i_mutex); + iput(inode); + } + + if (status) + mlog_errno(status); + return status; +} + +/* + * Step 2: By now, we've completed the journal recovery, we've stamped + * a clean local alloc on disk and dropped the node out of the + * recovery map. Dlm locks will no longer stall, so lets clear out the + * main bitmap. + */ +int ocfs2_complete_local_alloc_recovery(struct ocfs2_super *osb, + struct ocfs2_dinode *alloc) +{ + int status; + handle_t *handle; + struct buffer_head *main_bm_bh = NULL; + struct inode *main_bm_inode; + + main_bm_inode = ocfs2_get_system_file_inode(osb, + GLOBAL_BITMAP_SYSTEM_INODE, + OCFS2_INVALID_SLOT); + if (!main_bm_inode) { + status = -EINVAL; + mlog_errno(status); + goto out; + } + + mutex_lock(&main_bm_inode->i_mutex); + + status = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 1); + if (status < 0) { + mlog_errno(status); + goto out_mutex; + } + + handle = ocfs2_start_trans(osb, OCFS2_WINDOW_MOVE_CREDITS); + if (IS_ERR(handle)) { + status = PTR_ERR(handle); + handle = NULL; + mlog_errno(status); + goto out_unlock; + } + + /* we want the bitmap change to be recorded on disk asap */ + handle->h_sync = 1; + + status = ocfs2_sync_local_to_main(osb, handle, alloc, + main_bm_inode, main_bm_bh); + if (status < 0) + mlog_errno(status); + + ocfs2_commit_trans(osb, handle); + +out_unlock: + ocfs2_inode_unlock(main_bm_inode, 1); + +out_mutex: + mutex_unlock(&main_bm_inode->i_mutex); + + brelse(main_bm_bh); + + iput(main_bm_inode); + +out: + if (!status) + ocfs2_init_steal_slots(osb); + if (status) + mlog_errno(status); + return status; +} + +/* + * make sure we've got at least bits_wanted contiguous bits in the + * local alloc. You lose them when you drop i_mutex. + * + * We will add ourselves to the transaction passed in, but may start + * our own in order to shift windows. + */ +int ocfs2_reserve_local_alloc_bits(struct ocfs2_super *osb, + u32 bits_wanted, + struct ocfs2_alloc_context *ac) +{ + int status; + struct ocfs2_dinode *alloc; + struct inode *local_alloc_inode; + unsigned int free_bits; + + BUG_ON(!ac); + + local_alloc_inode = + ocfs2_get_system_file_inode(osb, + LOCAL_ALLOC_SYSTEM_INODE, + osb->slot_num); + if (!local_alloc_inode) { + status = -ENOENT; + mlog_errno(status); + goto bail; + } + + mutex_lock(&local_alloc_inode->i_mutex); + + /* + * We must double check state and allocator bits because + * another process may have changed them while holding i_mutex. + */ + spin_lock(&osb->osb_lock); + if (!ocfs2_la_state_enabled(osb) || + (bits_wanted > osb->local_alloc_bits)) { + spin_unlock(&osb->osb_lock); + status = -ENOSPC; + goto bail; + } + spin_unlock(&osb->osb_lock); + + alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data; + +#ifdef CONFIG_OCFS2_DEBUG_FS + if (le32_to_cpu(alloc->id1.bitmap1.i_used) != + ocfs2_local_alloc_count_bits(alloc)) { + ocfs2_error(osb->sb, "local alloc inode %llu says it has " + "%u used bits, but a count shows %u", + (unsigned long long)le64_to_cpu(alloc->i_blkno), + le32_to_cpu(alloc->id1.bitmap1.i_used), + ocfs2_local_alloc_count_bits(alloc)); + status = -EIO; + goto bail; + } +#endif + + free_bits = le32_to_cpu(alloc->id1.bitmap1.i_total) - + le32_to_cpu(alloc->id1.bitmap1.i_used); + if (bits_wanted > free_bits) { + /* uhoh, window change time. */ + status = + ocfs2_local_alloc_slide_window(osb, local_alloc_inode); + if (status < 0) { + if (status != -ENOSPC) + mlog_errno(status); + goto bail; + } + + /* + * Under certain conditions, the window slide code + * might have reduced the number of bits available or + * disabled the the local alloc entirely. Re-check + * here and return -ENOSPC if necessary. + */ + status = -ENOSPC; + if (!ocfs2_la_state_enabled(osb)) + goto bail; + + free_bits = le32_to_cpu(alloc->id1.bitmap1.i_total) - + le32_to_cpu(alloc->id1.bitmap1.i_used); + if (bits_wanted > free_bits) + goto bail; + } + + ac->ac_inode = local_alloc_inode; + /* We should never use localalloc from another slot */ + ac->ac_alloc_slot = osb->slot_num; + ac->ac_which = OCFS2_AC_USE_LOCAL; + get_bh(osb->local_alloc_bh); + ac->ac_bh = osb->local_alloc_bh; + status = 0; +bail: + if (status < 0 && local_alloc_inode) { + mutex_unlock(&local_alloc_inode->i_mutex); + iput(local_alloc_inode); + } + + trace_ocfs2_reserve_local_alloc_bits( + (unsigned long long)ac->ac_max_block, + bits_wanted, osb->slot_num, status); + + if (status) + mlog_errno(status); + return status; +} + +int ocfs2_claim_local_alloc_bits(struct ocfs2_super *osb, + handle_t *handle, + struct ocfs2_alloc_context *ac, + u32 bits_wanted, + u32 *bit_off, + u32 *num_bits) +{ + int status, start; + struct inode *local_alloc_inode; + void *bitmap; + struct ocfs2_dinode *alloc; + struct ocfs2_local_alloc *la; + + BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL); + + local_alloc_inode = ac->ac_inode; + alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data; + la = OCFS2_LOCAL_ALLOC(alloc); + + start = ocfs2_local_alloc_find_clear_bits(osb, alloc, &bits_wanted, + ac->ac_resv); + if (start == -1) { + /* TODO: Shouldn't we just BUG here? */ + status = -ENOSPC; + mlog_errno(status); + goto bail; + } + + bitmap = la->la_bitmap; + *bit_off = le32_to_cpu(la->la_bm_off) + start; + *num_bits = bits_wanted; + + status = ocfs2_journal_access_di(handle, + INODE_CACHE(local_alloc_inode), + osb->local_alloc_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (status < 0) { + mlog_errno(status); + goto bail; + } + + ocfs2_resmap_claimed_bits(&osb->osb_la_resmap, ac->ac_resv, start, + bits_wanted); + + while(bits_wanted--) + ocfs2_set_bit(start++, bitmap); + + le32_add_cpu(&alloc->id1.bitmap1.i_used, *num_bits); + ocfs2_journal_dirty(handle, osb->local_alloc_bh); + +bail: + if (status) + mlog_errno(status); + return status; +} + +int ocfs2_free_local_alloc_bits(struct ocfs2_super *osb, + handle_t *handle, + struct ocfs2_alloc_context *ac, + u32 bit_off, + u32 num_bits) +{ + int status, start; + u32 clear_bits; + struct inode *local_alloc_inode; + void *bitmap; + struct ocfs2_dinode *alloc; + struct ocfs2_local_alloc *la; + + BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL); + + local_alloc_inode = ac->ac_inode; + alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data; + la = OCFS2_LOCAL_ALLOC(alloc); + + bitmap = la->la_bitmap; + start = bit_off - le32_to_cpu(la->la_bm_off); + clear_bits = num_bits; + + status = ocfs2_journal_access_di(handle, + INODE_CACHE(local_alloc_inode), + osb->local_alloc_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (status < 0) { + mlog_errno(status); + goto bail; + } + + while (clear_bits--) + ocfs2_clear_bit(start++, bitmap); + + le32_add_cpu(&alloc->id1.bitmap1.i_used, -num_bits); + ocfs2_journal_dirty(handle, osb->local_alloc_bh); + +bail: + return status; +} + +static u32 ocfs2_local_alloc_count_bits(struct ocfs2_dinode *alloc) +{ + u32 count; + struct ocfs2_local_alloc *la = OCFS2_LOCAL_ALLOC(alloc); + + count = memweight(la->la_bitmap, le16_to_cpu(la->la_size)); + + trace_ocfs2_local_alloc_count_bits(count); + return count; +} + +static int ocfs2_local_alloc_find_clear_bits(struct ocfs2_super *osb, + struct ocfs2_dinode *alloc, + u32 *numbits, + struct ocfs2_alloc_reservation *resv) +{ + int numfound = 0, bitoff, left, startoff, lastzero; + int local_resv = 0; + struct ocfs2_alloc_reservation r; + void *bitmap = NULL; + struct ocfs2_reservation_map *resmap = &osb->osb_la_resmap; + + if (!alloc->id1.bitmap1.i_total) { + bitoff = -1; + goto bail; + } + + if (!resv) { + local_resv = 1; + ocfs2_resv_init_once(&r); + ocfs2_resv_set_type(&r, OCFS2_RESV_FLAG_TMP); + resv = &r; + } + + numfound = *numbits; + if (ocfs2_resmap_resv_bits(resmap, resv, &bitoff, &numfound) == 0) { + if (numfound < *numbits) + *numbits = numfound; + goto bail; + } + + /* + * Code error. While reservations are enabled, local + * allocation should _always_ go through them. + */ + BUG_ON(osb->osb_resv_level != 0); + + /* + * Reservations are disabled. Handle this the old way. + */ + + bitmap = OCFS2_LOCAL_ALLOC(alloc)->la_bitmap; + + numfound = bitoff = startoff = 0; + lastzero = -1; + left = le32_to_cpu(alloc->id1.bitmap1.i_total); + while ((bitoff = ocfs2_find_next_zero_bit(bitmap, left, startoff)) != -1) { + if (bitoff == left) { + /* mlog(0, "bitoff (%d) == left", bitoff); */ + break; + } + /* mlog(0, "Found a zero: bitoff = %d, startoff = %d, " + "numfound = %d\n", bitoff, startoff, numfound);*/ + + /* Ok, we found a zero bit... is it contig. or do we + * start over?*/ + if (bitoff == startoff) { + /* we found a zero */ + numfound++; + startoff++; + } else { + /* got a zero after some ones */ + numfound = 1; + startoff = bitoff+1; + } + /* we got everything we needed */ + if (numfound == *numbits) { + /* mlog(0, "Found it all!\n"); */ + break; + } + } + + trace_ocfs2_local_alloc_find_clear_bits_search_bitmap(bitoff, numfound); + + if (numfound == *numbits) + bitoff = startoff - numfound; + else + bitoff = -1; + +bail: + if (local_resv) + ocfs2_resv_discard(resmap, resv); + + trace_ocfs2_local_alloc_find_clear_bits(*numbits, + le32_to_cpu(alloc->id1.bitmap1.i_total), + bitoff, numfound); + + return bitoff; +} + +static void ocfs2_clear_local_alloc(struct ocfs2_dinode *alloc) +{ + struct ocfs2_local_alloc *la = OCFS2_LOCAL_ALLOC(alloc); + int i; + + alloc->id1.bitmap1.i_total = 0; + alloc->id1.bitmap1.i_used = 0; + la->la_bm_off = 0; + for(i = 0; i < le16_to_cpu(la->la_size); i++) + la->la_bitmap[i] = 0; +} + +#if 0 +/* turn this on and uncomment below to aid debugging window shifts. */ +static void ocfs2_verify_zero_bits(unsigned long *bitmap, + unsigned int start, + unsigned int count) +{ + unsigned int tmp = count; + while(tmp--) { + if (ocfs2_test_bit(start + tmp, bitmap)) { + printk("ocfs2_verify_zero_bits: start = %u, count = " + "%u\n", start, count); + printk("ocfs2_verify_zero_bits: bit %u is set!", + start + tmp); + BUG(); + } + } +} +#endif + +/* + * sync the local alloc to main bitmap. + * + * assumes you've already locked the main bitmap -- the bitmap inode + * passed is used for caching. + */ +static int ocfs2_sync_local_to_main(struct ocfs2_super *osb, + handle_t *handle, + struct ocfs2_dinode *alloc, + struct inode *main_bm_inode, + struct buffer_head *main_bm_bh) +{ + int status = 0; + int bit_off, left, count, start; + u64 la_start_blk; + u64 blkno; + void *bitmap; + struct ocfs2_local_alloc *la = OCFS2_LOCAL_ALLOC(alloc); + + trace_ocfs2_sync_local_to_main( + le32_to_cpu(alloc->id1.bitmap1.i_total), + le32_to_cpu(alloc->id1.bitmap1.i_used)); + + if (!alloc->id1.bitmap1.i_total) { + goto bail; + } + + if (le32_to_cpu(alloc->id1.bitmap1.i_used) == + le32_to_cpu(alloc->id1.bitmap1.i_total)) { + goto bail; + } + + la_start_blk = ocfs2_clusters_to_blocks(osb->sb, + le32_to_cpu(la->la_bm_off)); + bitmap = la->la_bitmap; + start = count = bit_off = 0; + left = le32_to_cpu(alloc->id1.bitmap1.i_total); + + while ((bit_off = ocfs2_find_next_zero_bit(bitmap, left, start)) + != -1) { + if ((bit_off < left) && (bit_off == start)) { + count++; + start++; + continue; + } + if (count) { + blkno = la_start_blk + + ocfs2_clusters_to_blocks(osb->sb, + start - count); + + trace_ocfs2_sync_local_to_main_free( + count, start - count, + (unsigned long long)la_start_blk, + (unsigned long long)blkno); + + status = ocfs2_release_clusters(handle, + main_bm_inode, + main_bm_bh, blkno, + count); + if (status < 0) { + mlog_errno(status); + goto bail; + } + } + if (bit_off >= left) + break; + count = 1; + start = bit_off + 1; + } + +bail: + if (status) + mlog_errno(status); + return status; +} + +enum ocfs2_la_event { + OCFS2_LA_EVENT_SLIDE, /* Normal window slide. */ + OCFS2_LA_EVENT_FRAGMENTED, /* The global bitmap has + * enough bits theoretically + * free, but a contiguous + * allocation could not be + * found. */ + OCFS2_LA_EVENT_ENOSPC, /* Global bitmap doesn't have + * enough bits free to satisfy + * our request. */ +}; +#define OCFS2_LA_ENABLE_INTERVAL (30 * HZ) +/* + * Given an event, calculate the size of our next local alloc window. + * + * This should always be called under i_mutex of the local alloc inode + * so that local alloc disabling doesn't race with processes trying to + * use the allocator. + * + * Returns the state which the local alloc was left in. This value can + * be ignored by some paths. + */ +static int ocfs2_recalc_la_window(struct ocfs2_super *osb, + enum ocfs2_la_event event) +{ + unsigned int bits; + int state; + + spin_lock(&osb->osb_lock); + if (osb->local_alloc_state == OCFS2_LA_DISABLED) { + WARN_ON_ONCE(osb->local_alloc_state == OCFS2_LA_DISABLED); + goto out_unlock; + } + + /* + * ENOSPC and fragmentation are treated similarly for now. + */ + if (event == OCFS2_LA_EVENT_ENOSPC || + event == OCFS2_LA_EVENT_FRAGMENTED) { + /* + * We ran out of contiguous space in the primary + * bitmap. Drastically reduce the number of bits used + * by local alloc until we have to disable it. + */ + bits = osb->local_alloc_bits >> 1; + if (bits > ocfs2_megabytes_to_clusters(osb->sb, 1)) { + /* + * By setting state to THROTTLED, we'll keep + * the number of local alloc bits used down + * until an event occurs which would give us + * reason to assume the bitmap situation might + * have changed. + */ + osb->local_alloc_state = OCFS2_LA_THROTTLED; + osb->local_alloc_bits = bits; + } else { + osb->local_alloc_state = OCFS2_LA_DISABLED; + } + queue_delayed_work(ocfs2_wq, &osb->la_enable_wq, + OCFS2_LA_ENABLE_INTERVAL); + goto out_unlock; + } + + /* + * Don't increase the size of the local alloc window until we + * know we might be able to fulfill the request. Otherwise, we + * risk bouncing around the global bitmap during periods of + * low space. + */ + if (osb->local_alloc_state != OCFS2_LA_THROTTLED) + osb->local_alloc_bits = osb->local_alloc_default_bits; + +out_unlock: + state = osb->local_alloc_state; + spin_unlock(&osb->osb_lock); + + return state; +} + +static int ocfs2_local_alloc_reserve_for_window(struct ocfs2_super *osb, + struct ocfs2_alloc_context **ac, + struct inode **bitmap_inode, + struct buffer_head **bitmap_bh) +{ + int status; + + *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL); + if (!(*ac)) { + status = -ENOMEM; + mlog_errno(status); + goto bail; + } + +retry_enospc: + (*ac)->ac_bits_wanted = osb->local_alloc_bits; + status = ocfs2_reserve_cluster_bitmap_bits(osb, *ac); + if (status == -ENOSPC) { + if (ocfs2_recalc_la_window(osb, OCFS2_LA_EVENT_ENOSPC) == + OCFS2_LA_DISABLED) + goto bail; + + ocfs2_free_ac_resource(*ac); + memset(*ac, 0, sizeof(struct ocfs2_alloc_context)); + goto retry_enospc; + } + if (status < 0) { + mlog_errno(status); + goto bail; + } + + *bitmap_inode = (*ac)->ac_inode; + igrab(*bitmap_inode); + *bitmap_bh = (*ac)->ac_bh; + get_bh(*bitmap_bh); + status = 0; +bail: + if ((status < 0) && *ac) { + ocfs2_free_alloc_context(*ac); + *ac = NULL; + } + + if (status) + mlog_errno(status); + return status; +} + +/* + * pass it the bitmap lock in lock_bh if you have it. + */ +static int ocfs2_local_alloc_new_window(struct ocfs2_super *osb, + handle_t *handle, + struct ocfs2_alloc_context *ac) +{ + int status = 0; + u32 cluster_off, cluster_count; + struct ocfs2_dinode *alloc = NULL; + struct ocfs2_local_alloc *la; + + alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data; + la = OCFS2_LOCAL_ALLOC(alloc); + + trace_ocfs2_local_alloc_new_window( + le32_to_cpu(alloc->id1.bitmap1.i_total), + osb->local_alloc_bits); + + /* Instruct the allocation code to try the most recently used + * cluster group. We'll re-record the group used this pass + * below. */ + ac->ac_last_group = osb->la_last_gd; + + /* we used the generic suballoc reserve function, but we set + * everything up nicely, so there's no reason why we can't use + * the more specific cluster api to claim bits. */ + status = ocfs2_claim_clusters(handle, ac, osb->local_alloc_bits, + &cluster_off, &cluster_count); + if (status == -ENOSPC) { +retry_enospc: + /* + * Note: We could also try syncing the journal here to + * allow use of any free bits which the current + * transaction can't give us access to. --Mark + */ + if (ocfs2_recalc_la_window(osb, OCFS2_LA_EVENT_FRAGMENTED) == + OCFS2_LA_DISABLED) + goto bail; + + ac->ac_bits_wanted = osb->local_alloc_bits; + status = ocfs2_claim_clusters(handle, ac, + osb->local_alloc_bits, + &cluster_off, + &cluster_count); + if (status == -ENOSPC) + goto retry_enospc; + /* + * We only shrunk the *minimum* number of in our + * request - it's entirely possible that the allocator + * might give us more than we asked for. + */ + if (status == 0) { + spin_lock(&osb->osb_lock); + osb->local_alloc_bits = cluster_count; + spin_unlock(&osb->osb_lock); + } + } + if (status < 0) { + if (status != -ENOSPC) + mlog_errno(status); + goto bail; + } + + osb->la_last_gd = ac->ac_last_group; + + la->la_bm_off = cpu_to_le32(cluster_off); + alloc->id1.bitmap1.i_total = cpu_to_le32(cluster_count); + /* just in case... In the future when we find space ourselves, + * we don't have to get all contiguous -- but we'll have to + * set all previously used bits in bitmap and update + * la_bits_set before setting the bits in the main bitmap. */ + alloc->id1.bitmap1.i_used = 0; + memset(OCFS2_LOCAL_ALLOC(alloc)->la_bitmap, 0, + le16_to_cpu(la->la_size)); + + ocfs2_resmap_restart(&osb->osb_la_resmap, cluster_count, + OCFS2_LOCAL_ALLOC(alloc)->la_bitmap); + + trace_ocfs2_local_alloc_new_window_result( + OCFS2_LOCAL_ALLOC(alloc)->la_bm_off, + le32_to_cpu(alloc->id1.bitmap1.i_total)); + +bail: + if (status) + mlog_errno(status); + return status; +} + +/* Note that we do *NOT* lock the local alloc inode here as + * it's been locked already for us. */ +static int ocfs2_local_alloc_slide_window(struct ocfs2_super *osb, + struct inode *local_alloc_inode) +{ + int status = 0; + struct buffer_head *main_bm_bh = NULL; + struct inode *main_bm_inode = NULL; + handle_t *handle = NULL; + struct ocfs2_dinode *alloc; + struct ocfs2_dinode *alloc_copy = NULL; + struct ocfs2_alloc_context *ac = NULL; + + ocfs2_recalc_la_window(osb, OCFS2_LA_EVENT_SLIDE); + + /* This will lock the main bitmap for us. */ + status = ocfs2_local_alloc_reserve_for_window(osb, + &ac, + &main_bm_inode, + &main_bm_bh); + if (status < 0) { + if (status != -ENOSPC) + mlog_errno(status); + goto bail; + } + + handle = ocfs2_start_trans(osb, OCFS2_WINDOW_MOVE_CREDITS); + if (IS_ERR(handle)) { + status = PTR_ERR(handle); + handle = NULL; + mlog_errno(status); + goto bail; + } + + alloc = (struct ocfs2_dinode *) osb->local_alloc_bh->b_data; + + /* We want to clear the local alloc before doing anything + * else, so that if we error later during this operation, + * local alloc shutdown won't try to double free main bitmap + * bits. Make a copy so the sync function knows which bits to + * free. */ + alloc_copy = kmalloc(osb->local_alloc_bh->b_size, GFP_NOFS); + if (!alloc_copy) { + status = -ENOMEM; + mlog_errno(status); + goto bail; + } + memcpy(alloc_copy, alloc, osb->local_alloc_bh->b_size); + + status = ocfs2_journal_access_di(handle, + INODE_CACHE(local_alloc_inode), + osb->local_alloc_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (status < 0) { + mlog_errno(status); + goto bail; + } + + ocfs2_clear_local_alloc(alloc); + ocfs2_journal_dirty(handle, osb->local_alloc_bh); + + status = ocfs2_sync_local_to_main(osb, handle, alloc_copy, + main_bm_inode, main_bm_bh); + if (status < 0) { + mlog_errno(status); + goto bail; + } + + status = ocfs2_local_alloc_new_window(osb, handle, ac); + if (status < 0) { + if (status != -ENOSPC) + mlog_errno(status); + goto bail; + } + + atomic_inc(&osb->alloc_stats.moves); + +bail: + if (handle) + ocfs2_commit_trans(osb, handle); + + brelse(main_bm_bh); + + if (main_bm_inode) + iput(main_bm_inode); + + kfree(alloc_copy); + + if (ac) + ocfs2_free_alloc_context(ac); + + if (status) + mlog_errno(status); + return status; +} + |