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Diffstat (limited to 'fs/nilfs2/alloc.c')
| -rw-r--r-- | fs/nilfs2/alloc.c | 785 |
1 files changed, 785 insertions, 0 deletions
diff --git a/fs/nilfs2/alloc.c b/fs/nilfs2/alloc.c new file mode 100644 index 000000000..8df0f3b78 --- /dev/null +++ b/fs/nilfs2/alloc.c @@ -0,0 +1,785 @@ +/* + * alloc.c - NILFS dat/inode allocator + * + * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation. + * + * 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Original code was written by Koji Sato <koji@osrg.net>. + * Two allocators were unified by Ryusuke Konishi <ryusuke@osrg.net>, + * Amagai Yoshiji <amagai@osrg.net>. + */ + +#include <linux/types.h> +#include <linux/buffer_head.h> +#include <linux/fs.h> +#include <linux/bitops.h> +#include <linux/slab.h> +#include "mdt.h" +#include "alloc.h" + + +/** + * nilfs_palloc_groups_per_desc_block - get the number of groups that a group + * descriptor block can maintain + * @inode: inode of metadata file using this allocator + */ +static inline unsigned long +nilfs_palloc_groups_per_desc_block(const struct inode *inode) +{ + return (1UL << inode->i_blkbits) / + sizeof(struct nilfs_palloc_group_desc); +} + +/** + * nilfs_palloc_groups_count - get maximum number of groups + * @inode: inode of metadata file using this allocator + */ +static inline unsigned long +nilfs_palloc_groups_count(const struct inode *inode) +{ + return 1UL << (BITS_PER_LONG - (inode->i_blkbits + 3 /* log2(8) */)); +} + +/** + * nilfs_palloc_init_blockgroup - initialize private variables for allocator + * @inode: inode of metadata file using this allocator + * @entry_size: size of the persistent object + */ +int nilfs_palloc_init_blockgroup(struct inode *inode, unsigned entry_size) +{ + struct nilfs_mdt_info *mi = NILFS_MDT(inode); + + mi->mi_bgl = kmalloc(sizeof(*mi->mi_bgl), GFP_NOFS); + if (!mi->mi_bgl) + return -ENOMEM; + + bgl_lock_init(mi->mi_bgl); + + nilfs_mdt_set_entry_size(inode, entry_size, 0); + + mi->mi_blocks_per_group = + DIV_ROUND_UP(nilfs_palloc_entries_per_group(inode), + mi->mi_entries_per_block) + 1; + /* Number of blocks in a group including entry blocks and + a bitmap block */ + mi->mi_blocks_per_desc_block = + nilfs_palloc_groups_per_desc_block(inode) * + mi->mi_blocks_per_group + 1; + /* Number of blocks per descriptor including the + descriptor block */ + return 0; +} + +/** + * nilfs_palloc_group - get group number and offset from an entry number + * @inode: inode of metadata file using this allocator + * @nr: serial number of the entry (e.g. inode number) + * @offset: pointer to store offset number in the group + */ +static unsigned long nilfs_palloc_group(const struct inode *inode, __u64 nr, + unsigned long *offset) +{ + __u64 group = nr; + + *offset = do_div(group, nilfs_palloc_entries_per_group(inode)); + return group; +} + +/** + * nilfs_palloc_desc_blkoff - get block offset of a group descriptor block + * @inode: inode of metadata file using this allocator + * @group: group number + * + * nilfs_palloc_desc_blkoff() returns block offset of the descriptor + * block which contains a descriptor of the specified group. + */ +static unsigned long +nilfs_palloc_desc_blkoff(const struct inode *inode, unsigned long group) +{ + unsigned long desc_block = + group / nilfs_palloc_groups_per_desc_block(inode); + return desc_block * NILFS_MDT(inode)->mi_blocks_per_desc_block; +} + +/** + * nilfs_palloc_bitmap_blkoff - get block offset of a bitmap block + * @inode: inode of metadata file using this allocator + * @group: group number + * + * nilfs_palloc_bitmap_blkoff() returns block offset of the bitmap + * block used to allocate/deallocate entries in the specified group. + */ +static unsigned long +nilfs_palloc_bitmap_blkoff(const struct inode *inode, unsigned long group) +{ + unsigned long desc_offset = + group % nilfs_palloc_groups_per_desc_block(inode); + return nilfs_palloc_desc_blkoff(inode, group) + 1 + + desc_offset * NILFS_MDT(inode)->mi_blocks_per_group; +} + +/** + * nilfs_palloc_group_desc_nfrees - get the number of free entries in a group + * @inode: inode of metadata file using this allocator + * @group: group number + * @desc: pointer to descriptor structure for the group + */ +static unsigned long +nilfs_palloc_group_desc_nfrees(struct inode *inode, unsigned long group, + const struct nilfs_palloc_group_desc *desc) +{ + unsigned long nfree; + + spin_lock(nilfs_mdt_bgl_lock(inode, group)); + nfree = le32_to_cpu(desc->pg_nfrees); + spin_unlock(nilfs_mdt_bgl_lock(inode, group)); + return nfree; +} + +/** + * nilfs_palloc_group_desc_add_entries - adjust count of free entries + * @inode: inode of metadata file using this allocator + * @group: group number + * @desc: pointer to descriptor structure for the group + * @n: delta to be added + */ +static void +nilfs_palloc_group_desc_add_entries(struct inode *inode, + unsigned long group, + struct nilfs_palloc_group_desc *desc, + u32 n) +{ + spin_lock(nilfs_mdt_bgl_lock(inode, group)); + le32_add_cpu(&desc->pg_nfrees, n); + spin_unlock(nilfs_mdt_bgl_lock(inode, group)); +} + +/** + * nilfs_palloc_entry_blkoff - get block offset of an entry block + * @inode: inode of metadata file using this allocator + * @nr: serial number of the entry (e.g. inode number) + */ +static unsigned long +nilfs_palloc_entry_blkoff(const struct inode *inode, __u64 nr) +{ + unsigned long group, group_offset; + + group = nilfs_palloc_group(inode, nr, &group_offset); + + return nilfs_palloc_bitmap_blkoff(inode, group) + 1 + + group_offset / NILFS_MDT(inode)->mi_entries_per_block; +} + +/** + * nilfs_palloc_desc_block_init - initialize buffer of a group descriptor block + * @inode: inode of metadata file + * @bh: buffer head of the buffer to be initialized + * @kaddr: kernel address mapped for the page including the buffer + */ +static void nilfs_palloc_desc_block_init(struct inode *inode, + struct buffer_head *bh, void *kaddr) +{ + struct nilfs_palloc_group_desc *desc = kaddr + bh_offset(bh); + unsigned long n = nilfs_palloc_groups_per_desc_block(inode); + __le32 nfrees; + + nfrees = cpu_to_le32(nilfs_palloc_entries_per_group(inode)); + while (n-- > 0) { + desc->pg_nfrees = nfrees; + desc++; + } +} + +static int nilfs_palloc_get_block(struct inode *inode, unsigned long blkoff, + int create, + void (*init_block)(struct inode *, + struct buffer_head *, + void *), + struct buffer_head **bhp, + struct nilfs_bh_assoc *prev, + spinlock_t *lock) +{ + int ret; + + spin_lock(lock); + if (prev->bh && blkoff == prev->blkoff) { + get_bh(prev->bh); + *bhp = prev->bh; + spin_unlock(lock); + return 0; + } + spin_unlock(lock); + + ret = nilfs_mdt_get_block(inode, blkoff, create, init_block, bhp); + if (!ret) { + spin_lock(lock); + /* + * The following code must be safe for change of the + * cache contents during the get block call. + */ + brelse(prev->bh); + get_bh(*bhp); + prev->bh = *bhp; + prev->blkoff = blkoff; + spin_unlock(lock); + } + return ret; +} + +/** + * nilfs_palloc_get_desc_block - get buffer head of a group descriptor block + * @inode: inode of metadata file using this allocator + * @group: group number + * @create: create flag + * @bhp: pointer to store the resultant buffer head + */ +static int nilfs_palloc_get_desc_block(struct inode *inode, + unsigned long group, + int create, struct buffer_head **bhp) +{ + struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache; + + return nilfs_palloc_get_block(inode, + nilfs_palloc_desc_blkoff(inode, group), + create, nilfs_palloc_desc_block_init, + bhp, &cache->prev_desc, &cache->lock); +} + +/** + * nilfs_palloc_get_bitmap_block - get buffer head of a bitmap block + * @inode: inode of metadata file using this allocator + * @group: group number + * @create: create flag + * @bhp: pointer to store the resultant buffer head + */ +static int nilfs_palloc_get_bitmap_block(struct inode *inode, + unsigned long group, + int create, struct buffer_head **bhp) +{ + struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache; + + return nilfs_palloc_get_block(inode, + nilfs_palloc_bitmap_blkoff(inode, group), + create, NULL, bhp, + &cache->prev_bitmap, &cache->lock); +} + +/** + * nilfs_palloc_get_entry_block - get buffer head of an entry block + * @inode: inode of metadata file using this allocator + * @nr: serial number of the entry (e.g. inode number) + * @create: create flag + * @bhp: pointer to store the resultant buffer head + */ +int nilfs_palloc_get_entry_block(struct inode *inode, __u64 nr, + int create, struct buffer_head **bhp) +{ + struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache; + + return nilfs_palloc_get_block(inode, + nilfs_palloc_entry_blkoff(inode, nr), + create, NULL, bhp, + &cache->prev_entry, &cache->lock); +} + +/** + * nilfs_palloc_block_get_group_desc - get kernel address of a group descriptor + * @inode: inode of metadata file using this allocator + * @group: group number + * @bh: buffer head of the buffer storing the group descriptor block + * @kaddr: kernel address mapped for the page including the buffer + */ +static struct nilfs_palloc_group_desc * +nilfs_palloc_block_get_group_desc(const struct inode *inode, + unsigned long group, + const struct buffer_head *bh, void *kaddr) +{ + return (struct nilfs_palloc_group_desc *)(kaddr + bh_offset(bh)) + + group % nilfs_palloc_groups_per_desc_block(inode); +} + +/** + * nilfs_palloc_block_get_entry - get kernel address of an entry + * @inode: inode of metadata file using this allocator + * @nr: serial number of the entry (e.g. inode number) + * @bh: buffer head of the buffer storing the entry block + * @kaddr: kernel address mapped for the page including the buffer + */ +void *nilfs_palloc_block_get_entry(const struct inode *inode, __u64 nr, + const struct buffer_head *bh, void *kaddr) +{ + unsigned long entry_offset, group_offset; + + nilfs_palloc_group(inode, nr, &group_offset); + entry_offset = group_offset % NILFS_MDT(inode)->mi_entries_per_block; + + return kaddr + bh_offset(bh) + + entry_offset * NILFS_MDT(inode)->mi_entry_size; +} + +/** + * nilfs_palloc_find_available_slot - find available slot in a group + * @inode: inode of metadata file using this allocator + * @group: group number + * @target: offset number of an entry in the group (start point) + * @bitmap: bitmap of the group + * @bsize: size in bits + */ +static int nilfs_palloc_find_available_slot(struct inode *inode, + unsigned long group, + unsigned long target, + unsigned char *bitmap, + int bsize) +{ + int curr, pos, end, i; + + if (target > 0) { + end = (target + BITS_PER_LONG - 1) & ~(BITS_PER_LONG - 1); + if (end > bsize) + end = bsize; + pos = nilfs_find_next_zero_bit(bitmap, end, target); + if (pos < end && + !nilfs_set_bit_atomic( + nilfs_mdt_bgl_lock(inode, group), pos, bitmap)) + return pos; + } else + end = 0; + + for (i = 0, curr = end; + i < bsize; + i += BITS_PER_LONG, curr += BITS_PER_LONG) { + /* wrap around */ + if (curr >= bsize) + curr = 0; + while (*((unsigned long *)bitmap + curr / BITS_PER_LONG) + != ~0UL) { + end = curr + BITS_PER_LONG; + if (end > bsize) + end = bsize; + pos = nilfs_find_next_zero_bit(bitmap, end, curr); + if ((pos < end) && + !nilfs_set_bit_atomic( + nilfs_mdt_bgl_lock(inode, group), pos, + bitmap)) + return pos; + } + } + return -ENOSPC; +} + +/** + * nilfs_palloc_rest_groups_in_desc_block - get the remaining number of groups + * in a group descriptor block + * @inode: inode of metadata file using this allocator + * @curr: current group number + * @max: maximum number of groups + */ +static unsigned long +nilfs_palloc_rest_groups_in_desc_block(const struct inode *inode, + unsigned long curr, unsigned long max) +{ + return min_t(unsigned long, + nilfs_palloc_groups_per_desc_block(inode) - + curr % nilfs_palloc_groups_per_desc_block(inode), + max - curr + 1); +} + +/** + * nilfs_palloc_count_desc_blocks - count descriptor blocks number + * @inode: inode of metadata file using this allocator + * @desc_blocks: descriptor blocks number [out] + */ +static int nilfs_palloc_count_desc_blocks(struct inode *inode, + unsigned long *desc_blocks) +{ + __u64 blknum; + int ret; + + ret = nilfs_bmap_last_key(NILFS_I(inode)->i_bmap, &blknum); + if (likely(!ret)) + *desc_blocks = DIV_ROUND_UP( + (unsigned long)blknum, + NILFS_MDT(inode)->mi_blocks_per_desc_block); + return ret; +} + +/** + * nilfs_palloc_mdt_file_can_grow - check potential opportunity for + * MDT file growing + * @inode: inode of metadata file using this allocator + * @desc_blocks: known current descriptor blocks count + */ +static inline bool nilfs_palloc_mdt_file_can_grow(struct inode *inode, + unsigned long desc_blocks) +{ + return (nilfs_palloc_groups_per_desc_block(inode) * desc_blocks) < + nilfs_palloc_groups_count(inode); +} + +/** + * nilfs_palloc_count_max_entries - count max number of entries that can be + * described by descriptor blocks count + * @inode: inode of metadata file using this allocator + * @nused: current number of used entries + * @nmaxp: max number of entries [out] + */ +int nilfs_palloc_count_max_entries(struct inode *inode, u64 nused, u64 *nmaxp) +{ + unsigned long desc_blocks = 0; + u64 entries_per_desc_block, nmax; + int err; + + err = nilfs_palloc_count_desc_blocks(inode, &desc_blocks); + if (unlikely(err)) + return err; + + entries_per_desc_block = (u64)nilfs_palloc_entries_per_group(inode) * + nilfs_palloc_groups_per_desc_block(inode); + nmax = entries_per_desc_block * desc_blocks; + + if (nused == nmax && + nilfs_palloc_mdt_file_can_grow(inode, desc_blocks)) + nmax += entries_per_desc_block; + + if (nused > nmax) + return -ERANGE; + + *nmaxp = nmax; + return 0; +} + +/** + * nilfs_palloc_prepare_alloc_entry - prepare to allocate a persistent object + * @inode: inode of metadata file using this allocator + * @req: nilfs_palloc_req structure exchanged for the allocation + */ +int nilfs_palloc_prepare_alloc_entry(struct inode *inode, + struct nilfs_palloc_req *req) +{ + struct buffer_head *desc_bh, *bitmap_bh; + struct nilfs_palloc_group_desc *desc; + unsigned char *bitmap; + void *desc_kaddr, *bitmap_kaddr; + unsigned long group, maxgroup, ngroups; + unsigned long group_offset, maxgroup_offset; + unsigned long n, entries_per_group, groups_per_desc_block; + unsigned long i, j; + int pos, ret; + + ngroups = nilfs_palloc_groups_count(inode); + maxgroup = ngroups - 1; + group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset); + entries_per_group = nilfs_palloc_entries_per_group(inode); + groups_per_desc_block = nilfs_palloc_groups_per_desc_block(inode); + + for (i = 0; i < ngroups; i += n) { + if (group >= ngroups) { + /* wrap around */ + group = 0; + maxgroup = nilfs_palloc_group(inode, req->pr_entry_nr, + &maxgroup_offset) - 1; + } + ret = nilfs_palloc_get_desc_block(inode, group, 1, &desc_bh); + if (ret < 0) + return ret; + desc_kaddr = kmap(desc_bh->b_page); + desc = nilfs_palloc_block_get_group_desc( + inode, group, desc_bh, desc_kaddr); + n = nilfs_palloc_rest_groups_in_desc_block(inode, group, + maxgroup); + for (j = 0; j < n; j++, desc++, group++) { + if (nilfs_palloc_group_desc_nfrees(inode, group, desc) + > 0) { + ret = nilfs_palloc_get_bitmap_block( + inode, group, 1, &bitmap_bh); + if (ret < 0) + goto out_desc; + bitmap_kaddr = kmap(bitmap_bh->b_page); + bitmap = bitmap_kaddr + bh_offset(bitmap_bh); + pos = nilfs_palloc_find_available_slot( + inode, group, group_offset, bitmap, + entries_per_group); + if (pos >= 0) { + /* found a free entry */ + nilfs_palloc_group_desc_add_entries( + inode, group, desc, -1); + req->pr_entry_nr = + entries_per_group * group + pos; + kunmap(desc_bh->b_page); + kunmap(bitmap_bh->b_page); + + req->pr_desc_bh = desc_bh; + req->pr_bitmap_bh = bitmap_bh; + return 0; + } + kunmap(bitmap_bh->b_page); + brelse(bitmap_bh); + } + + group_offset = 0; + } + + kunmap(desc_bh->b_page); + brelse(desc_bh); + } + + /* no entries left */ + return -ENOSPC; + + out_desc: + kunmap(desc_bh->b_page); + brelse(desc_bh); + return ret; +} + +/** + * nilfs_palloc_commit_alloc_entry - finish allocation of a persistent object + * @inode: inode of metadata file using this allocator + * @req: nilfs_palloc_req structure exchanged for the allocation + */ +void nilfs_palloc_commit_alloc_entry(struct inode *inode, + struct nilfs_palloc_req *req) +{ + mark_buffer_dirty(req->pr_bitmap_bh); + mark_buffer_dirty(req->pr_desc_bh); + nilfs_mdt_mark_dirty(inode); + + brelse(req->pr_bitmap_bh); + brelse(req->pr_desc_bh); +} + +/** + * nilfs_palloc_commit_free_entry - finish deallocating a persistent object + * @inode: inode of metadata file using this allocator + * @req: nilfs_palloc_req structure exchanged for the removal + */ +void nilfs_palloc_commit_free_entry(struct inode *inode, + struct nilfs_palloc_req *req) +{ + struct nilfs_palloc_group_desc *desc; + unsigned long group, group_offset; + unsigned char *bitmap; + void *desc_kaddr, *bitmap_kaddr; + + group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset); + desc_kaddr = kmap(req->pr_desc_bh->b_page); + desc = nilfs_palloc_block_get_group_desc(inode, group, + req->pr_desc_bh, desc_kaddr); + bitmap_kaddr = kmap(req->pr_bitmap_bh->b_page); + bitmap = bitmap_kaddr + bh_offset(req->pr_bitmap_bh); + + if (!nilfs_clear_bit_atomic(nilfs_mdt_bgl_lock(inode, group), + group_offset, bitmap)) + printk(KERN_WARNING "%s: entry number %llu already freed\n", + __func__, (unsigned long long)req->pr_entry_nr); + else + nilfs_palloc_group_desc_add_entries(inode, group, desc, 1); + + kunmap(req->pr_bitmap_bh->b_page); + kunmap(req->pr_desc_bh->b_page); + + mark_buffer_dirty(req->pr_desc_bh); + mark_buffer_dirty(req->pr_bitmap_bh); + nilfs_mdt_mark_dirty(inode); + + brelse(req->pr_bitmap_bh); + brelse(req->pr_desc_bh); +} + +/** + * nilfs_palloc_abort_alloc_entry - cancel allocation of a persistent object + * @inode: inode of metadata file using this allocator + * @req: nilfs_palloc_req structure exchanged for the allocation + */ +void nilfs_palloc_abort_alloc_entry(struct inode *inode, + struct nilfs_palloc_req *req) +{ + struct nilfs_palloc_group_desc *desc; + void *desc_kaddr, *bitmap_kaddr; + unsigned char *bitmap; + unsigned long group, group_offset; + + group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset); + desc_kaddr = kmap(req->pr_desc_bh->b_page); + desc = nilfs_palloc_block_get_group_desc(inode, group, + req->pr_desc_bh, desc_kaddr); + bitmap_kaddr = kmap(req->pr_bitmap_bh->b_page); + bitmap = bitmap_kaddr + bh_offset(req->pr_bitmap_bh); + if (!nilfs_clear_bit_atomic(nilfs_mdt_bgl_lock(inode, group), + group_offset, bitmap)) + printk(KERN_WARNING "%s: entry number %llu already freed\n", + __func__, (unsigned long long)req->pr_entry_nr); + else + nilfs_palloc_group_desc_add_entries(inode, group, desc, 1); + + kunmap(req->pr_bitmap_bh->b_page); + kunmap(req->pr_desc_bh->b_page); + + brelse(req->pr_bitmap_bh); + brelse(req->pr_desc_bh); + + req->pr_entry_nr = 0; + req->pr_bitmap_bh = NULL; + req->pr_desc_bh = NULL; +} + +/** + * nilfs_palloc_prepare_free_entry - prepare to deallocate a persistent object + * @inode: inode of metadata file using this allocator + * @req: nilfs_palloc_req structure exchanged for the removal + */ +int nilfs_palloc_prepare_free_entry(struct inode *inode, + struct nilfs_palloc_req *req) +{ + struct buffer_head *desc_bh, *bitmap_bh; + unsigned long group, group_offset; + int ret; + + group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset); + ret = nilfs_palloc_get_desc_block(inode, group, 1, &desc_bh); + if (ret < 0) + return ret; + ret = nilfs_palloc_get_bitmap_block(inode, group, 1, &bitmap_bh); + if (ret < 0) { + brelse(desc_bh); + return ret; + } + + req->pr_desc_bh = desc_bh; + req->pr_bitmap_bh = bitmap_bh; + return 0; +} + +/** + * nilfs_palloc_abort_free_entry - cancel deallocating a persistent object + * @inode: inode of metadata file using this allocator + * @req: nilfs_palloc_req structure exchanged for the removal + */ +void nilfs_palloc_abort_free_entry(struct inode *inode, + struct nilfs_palloc_req *req) +{ + brelse(req->pr_bitmap_bh); + brelse(req->pr_desc_bh); + + req->pr_entry_nr = 0; + req->pr_bitmap_bh = NULL; + req->pr_desc_bh = NULL; +} + +/** + * nilfs_palloc_group_is_in - judge if an entry is in a group + * @inode: inode of metadata file using this allocator + * @group: group number + * @nr: serial number of the entry (e.g. inode number) + */ +static int +nilfs_palloc_group_is_in(struct inode *inode, unsigned long group, __u64 nr) +{ + __u64 first, last; + + first = group * nilfs_palloc_entries_per_group(inode); + last = first + nilfs_palloc_entries_per_group(inode) - 1; + return (nr >= first) && (nr <= last); +} + +/** + * nilfs_palloc_freev - deallocate a set of persistent objects + * @inode: inode of metadata file using this allocator + * @entry_nrs: array of entry numbers to be deallocated + * @nitems: number of entries stored in @entry_nrs + */ +int nilfs_palloc_freev(struct inode *inode, __u64 *entry_nrs, size_t nitems) +{ + struct buffer_head *desc_bh, *bitmap_bh; + struct nilfs_palloc_group_desc *desc; + unsigned char *bitmap; + void *desc_kaddr, *bitmap_kaddr; + unsigned long group, group_offset; + int i, j, n, ret; + + for (i = 0; i < nitems; i = j) { + group = nilfs_palloc_group(inode, entry_nrs[i], &group_offset); + ret = nilfs_palloc_get_desc_block(inode, group, 0, &desc_bh); + if (ret < 0) + return ret; + ret = nilfs_palloc_get_bitmap_block(inode, group, 0, + &bitmap_bh); + if (ret < 0) { + brelse(desc_bh); + return ret; + } + desc_kaddr = kmap(desc_bh->b_page); + desc = nilfs_palloc_block_get_group_desc( + inode, group, desc_bh, desc_kaddr); + bitmap_kaddr = kmap(bitmap_bh->b_page); + bitmap = bitmap_kaddr + bh_offset(bitmap_bh); + for (j = i, n = 0; + (j < nitems) && nilfs_palloc_group_is_in(inode, group, + entry_nrs[j]); + j++) { + nilfs_palloc_group(inode, entry_nrs[j], &group_offset); + if (!nilfs_clear_bit_atomic( + nilfs_mdt_bgl_lock(inode, group), + group_offset, bitmap)) { + printk(KERN_WARNING + "%s: entry number %llu already freed\n", + __func__, + (unsigned long long)entry_nrs[j]); + } else { + n++; + } + } + nilfs_palloc_group_desc_add_entries(inode, group, desc, n); + + kunmap(bitmap_bh->b_page); + kunmap(desc_bh->b_page); + + mark_buffer_dirty(desc_bh); + mark_buffer_dirty(bitmap_bh); + nilfs_mdt_mark_dirty(inode); + + brelse(bitmap_bh); + brelse(desc_bh); + } + return 0; +} + +void nilfs_palloc_setup_cache(struct inode *inode, + struct nilfs_palloc_cache *cache) +{ + NILFS_MDT(inode)->mi_palloc_cache = cache; + spin_lock_init(&cache->lock); +} + +void nilfs_palloc_clear_cache(struct inode *inode) +{ + struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache; + + spin_lock(&cache->lock); + brelse(cache->prev_desc.bh); + brelse(cache->prev_bitmap.bh); + brelse(cache->prev_entry.bh); + cache->prev_desc.bh = NULL; + cache->prev_bitmap.bh = NULL; + cache->prev_entry.bh = NULL; + spin_unlock(&cache->lock); +} + +void nilfs_palloc_destroy_cache(struct inode *inode) +{ + nilfs_palloc_clear_cache(inode); + NILFS_MDT(inode)->mi_palloc_cache = NULL; +} |