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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
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#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 * * Return: Number of groups that a group descriptor block can maintain. */static inline unsigned longnilfs_palloc_groups_per_desc_block(const struct inode *inode){ return i_blocksize(inode) / sizeof(struct nilfs_palloc_group_desc);}
/** * nilfs_palloc_groups_count - get maximum number of groups * @inode: inode of metadata file using this allocator * * Return: Maximum number of groups. */static inline unsigned longnilfs_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 * * Return: 0 on success, or a negative error code on failure. */int nilfs_palloc_init_blockgroup(struct inode *inode, unsigned int entry_size){ struct nilfs_mdt_info *mi = NILFS_MDT(inode);
mi->mi_bgl = kmalloc_obj(*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 * * Return: Number of the group that contains the entry with the index * specified by @nr. */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 * * Return: Index number in the metadata file of the descriptor block of * the group specified by @group. */static unsigned longnilfs_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. * * Return: Index number in the metadata file of the bitmap block of * the group specified by @group. */static unsigned longnilfs_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 * @desc: pointer to descriptor structure for the group * @lock: spin lock protecting @desc * * Return: Number of free entries written in the group descriptor @desc. */static unsigned longnilfs_palloc_group_desc_nfrees(const struct nilfs_palloc_group_desc *desc, spinlock_t *lock){ unsigned long nfree;
spin_lock(lock); nfree = le32_to_cpu(desc->pg_nfrees); spin_unlock(lock); return nfree;}
/** * nilfs_palloc_group_desc_add_entries - adjust count of free entries * @desc: pointer to descriptor structure for the group * @lock: spin lock protecting @desc * @n: delta to be added * * Return: Number of free entries after adjusting the group descriptor * @desc. */static u32nilfs_palloc_group_desc_add_entries(struct nilfs_palloc_group_desc *desc, spinlock_t *lock, u32 n){ u32 nfree;
spin_lock(lock); le32_add_cpu(&desc->pg_nfrees, n); nfree = le32_to_cpu(desc->pg_nfrees); spin_unlock(lock); return nfree;}
/** * 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) * * Return: Index number in the metadata file of the block containing * the entry specified by @nr. */static unsigned longnilfs_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 * @from: kernel address mapped for a chunk of the block * * This function does not yet support the case where block size > PAGE_SIZE. */static void nilfs_palloc_desc_block_init(struct inode *inode, struct buffer_head *bh, void *from){ struct nilfs_palloc_group_desc *desc = from; 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 && likely(buffer_uptodate(prev->bh))) { 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_delete_block - delete a block on the persistent allocator file * @inode: inode of metadata file using this allocator * @blkoff: block offset * @prev: nilfs_bh_assoc struct of the last used buffer * @lock: spin lock protecting @prev * * Return: 0 on success, or one of the following negative error codes on * failure: * * %-EIO - I/O error (including metadata corruption). * * %-ENOENT - Non-existent block. * * %-ENOMEM - Insufficient memory available. */static int nilfs_palloc_delete_block(struct inode *inode, unsigned long blkoff, struct nilfs_bh_assoc *prev, spinlock_t *lock){ spin_lock(lock); if (prev->bh && blkoff == prev->blkoff) { brelse(prev->bh); prev->bh = NULL; } spin_unlock(lock); return nilfs_mdt_delete_block(inode, blkoff);}
/** * 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 * * Return: 0 on success, or a negative error code on failure. */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 * * Return: 0 on success, or a negative error code on failure. */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_delete_bitmap_block - delete a bitmap block * @inode: inode of metadata file using this allocator * @group: group number * * Return: 0 on success, or a negative error code on failure. */static int nilfs_palloc_delete_bitmap_block(struct inode *inode, unsigned long group){ struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache;
return nilfs_palloc_delete_block(inode, nilfs_palloc_bitmap_blkoff(inode, group), &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 * * Return: 0 on success, or a negative error code on failure. */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_delete_entry_block - delete an entry block * @inode: inode of metadata file using this allocator * @nr: serial number of the entry * * Return: 0 on success, or a negative error code on failure. */static int nilfs_palloc_delete_entry_block(struct inode *inode, __u64 nr){ struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache;
return nilfs_palloc_delete_block(inode, nilfs_palloc_entry_blkoff(inode, nr), &cache->prev_entry, &cache->lock);}
/** * nilfs_palloc_group_desc_offset - calculate the byte offset of a group * descriptor in the folio containing it * @inode: inode of metadata file using this allocator * @group: group number * @bh: buffer head of the group descriptor block * * Return: Byte offset in the folio of the group descriptor for @group. */static size_t nilfs_palloc_group_desc_offset(const struct inode *inode, unsigned long group, const struct buffer_head *bh){ return offset_in_folio(bh->b_folio, bh->b_data) + sizeof(struct nilfs_palloc_group_desc) * (group % nilfs_palloc_groups_per_desc_block(inode));}
/** * nilfs_palloc_bitmap_offset - calculate the byte offset of a bitmap block * in the folio containing it * @bh: buffer head of the bitmap block * * Return: Byte offset in the folio of the bitmap block for @bh. */static size_t nilfs_palloc_bitmap_offset(const struct buffer_head *bh){ return offset_in_folio(bh->b_folio, bh->b_data);}
/** * nilfs_palloc_entry_offset - calculate the byte offset of an entry in the * folio containing it * @inode: inode of metadata file using this allocator * @nr: serial number of the entry (e.g. inode number) * @bh: buffer head of the entry block * * Return: Byte offset in the folio of the entry @nr. */size_t nilfs_palloc_entry_offset(const struct inode *inode, __u64 nr, const struct buffer_head *bh){ unsigned long entry_index_in_group, entry_index_in_block;
nilfs_palloc_group(inode, nr, &entry_index_in_group); entry_index_in_block = entry_index_in_group % NILFS_MDT(inode)->mi_entries_per_block;
return offset_in_folio(bh->b_folio, bh->b_data) + entry_index_in_block * NILFS_MDT(inode)->mi_entry_size;}
/** * nilfs_palloc_find_available_slot - find available slot in a group * @bitmap: bitmap of the group * @target: offset number of an entry in the group (start point) * @bsize: size in bits * @lock: spin lock protecting @bitmap * @wrap: whether to wrap around * * Return: Offset number within the group of the found free entry, or * %-ENOSPC if not found. */static int nilfs_palloc_find_available_slot(unsigned char *bitmap, unsigned long target, unsigned int bsize, spinlock_t *lock, bool wrap){ int pos, end = bsize;
if (likely(target < bsize)) { pos = target; do { pos = nilfs_find_next_zero_bit(bitmap, end, pos); if (pos >= end) break; if (!nilfs_set_bit_atomic(lock, pos, bitmap)) return pos; } while (++pos < end);
end = target; } if (!wrap) return -ENOSPC;
/* wrap around */ for (pos = 0; pos < end; pos++) { pos = nilfs_find_next_zero_bit(bitmap, end, pos); if (pos >= end) break; if (!nilfs_set_bit_atomic(lock, 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 * * Return: Number of remaining descriptors (= groups) managed by the descriptor * block. */static unsigned longnilfs_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] * * Return: 0 on success, or a negative error code on failure. */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 * * Return: true if a group can be added in the metadata file, false if not. */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] * * Return: 0 on success, or one of the following negative error codes on * failure: * * %-EIO - I/O error (including metadata corruption). * * %-ENOMEM - Insufficient memory available. * * %-ERANGE - Number of entries in use is out of range. */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 * @wrap: whether to wrap around * * Return: 0 on success, or one of the following negative error codes on * failure: * * %-EIO - I/O error (including metadata corruption). * * %-ENOMEM - Insufficient memory available. * * %-ENOSPC - Entries exhausted (No entries available for allocation). * * %-EROFS - Read only filesystem */int nilfs_palloc_prepare_alloc_entry(struct inode *inode, struct nilfs_palloc_req *req, bool wrap){ struct buffer_head *desc_bh, *bitmap_bh; struct nilfs_palloc_group_desc *desc; unsigned char *bitmap; size_t doff, boff; unsigned long group, maxgroup, ngroups; unsigned long group_offset, maxgroup_offset; unsigned long n, entries_per_group; unsigned long i, j; spinlock_t *lock; 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);
for (i = 0; i < ngroups; i += n) { if (group >= ngroups && wrap) { /* 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;
doff = nilfs_palloc_group_desc_offset(inode, group, desc_bh); desc = kmap_local_folio(desc_bh->b_folio, doff); n = nilfs_palloc_rest_groups_in_desc_block(inode, group, maxgroup); for (j = 0; j < n; j++, group++, group_offset = 0) { lock = nilfs_mdt_bgl_lock(inode, group); if (nilfs_palloc_group_desc_nfrees(&desc[j], lock) == 0) continue;
kunmap_local(desc); ret = nilfs_palloc_get_bitmap_block(inode, group, 1, &bitmap_bh); if (unlikely(ret < 0)) { brelse(desc_bh); return ret; }
/* * Re-kmap the folio containing the first (and * subsequent) group descriptors. */ desc = kmap_local_folio(desc_bh->b_folio, doff);
boff = nilfs_palloc_bitmap_offset(bitmap_bh); bitmap = kmap_local_folio(bitmap_bh->b_folio, boff); pos = nilfs_palloc_find_available_slot( bitmap, group_offset, entries_per_group, lock, wrap); /* * Since the search for a free slot in the second and * subsequent bitmap blocks always starts from the * beginning, the wrap flag only has an effect on the * first search. */ kunmap_local(bitmap); if (pos >= 0) goto found;
brelse(bitmap_bh); }
kunmap_local(desc); brelse(desc_bh); }
/* no entries left */ return -ENOSPC;
found: /* found a free entry */ nilfs_palloc_group_desc_add_entries(&desc[j], lock, -1); req->pr_entry_nr = entries_per_group * group + pos; kunmap_local(desc);
req->pr_desc_bh = desc_bh; req->pr_bitmap_bh = bitmap_bh; return 0;}
/** * 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){ unsigned long group, group_offset; size_t doff, boff; struct nilfs_palloc_group_desc *desc; unsigned char *bitmap; spinlock_t *lock;
group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset); doff = nilfs_palloc_group_desc_offset(inode, group, req->pr_desc_bh); desc = kmap_local_folio(req->pr_desc_bh->b_folio, doff);
boff = nilfs_palloc_bitmap_offset(req->pr_bitmap_bh); bitmap = kmap_local_folio(req->pr_bitmap_bh->b_folio, boff); lock = nilfs_mdt_bgl_lock(inode, group);
if (!nilfs_clear_bit_atomic(lock, group_offset, bitmap)) nilfs_warn(inode->i_sb, "%s (ino=%llu): entry number %llu already freed", __func__, inode->i_ino, (unsigned long long)req->pr_entry_nr); else nilfs_palloc_group_desc_add_entries(desc, lock, 1);
kunmap_local(bitmap); kunmap_local(desc);
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; size_t doff, boff; unsigned char *bitmap; unsigned long group, group_offset; spinlock_t *lock;
group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset); doff = nilfs_palloc_group_desc_offset(inode, group, req->pr_desc_bh); desc = kmap_local_folio(req->pr_desc_bh->b_folio, doff);
boff = nilfs_palloc_bitmap_offset(req->pr_bitmap_bh); bitmap = kmap_local_folio(req->pr_bitmap_bh->b_folio, boff); lock = nilfs_mdt_bgl_lock(inode, group);
if (!nilfs_clear_bit_atomic(lock, group_offset, bitmap)) nilfs_warn(inode->i_sb, "%s (ino=%llu): entry number %llu already freed", __func__, inode->i_ino, (unsigned long long)req->pr_entry_nr); else nilfs_palloc_group_desc_add_entries(desc, lock, 1);
kunmap_local(bitmap); kunmap_local(desc);
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 * * Return: 0 on success, or a negative error code on failure. */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_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 * * Return: 0 on success, or a negative error code on failure. */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; size_t doff, boff; unsigned long group, group_offset; __u64 group_min_nr, last_nrs[8]; const unsigned long epg = nilfs_palloc_entries_per_group(inode); const unsigned int epb = NILFS_MDT(inode)->mi_entries_per_block; unsigned int entry_start, end, pos; spinlock_t *lock; int i, j, k, ret; u32 nfree;
for (i = 0; i < nitems; i = j) { int change_group = false; int nempties = 0, n = 0;
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; }
/* Get the first entry number of the group */ group_min_nr = (__u64)group * epg;
boff = nilfs_palloc_bitmap_offset(bitmap_bh); bitmap = kmap_local_folio(bitmap_bh->b_folio, boff); lock = nilfs_mdt_bgl_lock(inode, group);
j = i; entry_start = rounddown(group_offset, epb); do { if (!nilfs_clear_bit_atomic(lock, group_offset, bitmap)) { nilfs_warn(inode->i_sb, "%s (ino=%llu): entry number %llu already freed", __func__, inode->i_ino, (unsigned long long)entry_nrs[j]); } else { n++; }
j++; if (j >= nitems || entry_nrs[j] < group_min_nr || entry_nrs[j] >= group_min_nr + epg) { change_group = true; } else { group_offset = entry_nrs[j] - group_min_nr; if (group_offset >= entry_start && group_offset < entry_start + epb) { /* This entry is in the same block */ continue; } }
/* Test if the entry block is empty or not */ end = entry_start + epb; pos = nilfs_find_next_bit(bitmap, end, entry_start); if (pos >= end) { last_nrs[nempties++] = entry_nrs[j - 1]; if (nempties >= ARRAY_SIZE(last_nrs)) break; }
if (change_group) break;
/* Go on to the next entry block */ entry_start = rounddown(group_offset, epb); } while (true);
kunmap_local(bitmap); mark_buffer_dirty(bitmap_bh); brelse(bitmap_bh);
for (k = 0; k < nempties; k++) { ret = nilfs_palloc_delete_entry_block(inode, last_nrs[k]); if (ret && ret != -ENOENT) nilfs_warn(inode->i_sb, "error %d deleting block that object (entry=%llu, ino=%llu) belongs to", ret, (unsigned long long)last_nrs[k], inode->i_ino); }
doff = nilfs_palloc_group_desc_offset(inode, group, desc_bh); desc = kmap_local_folio(desc_bh->b_folio, doff); nfree = nilfs_palloc_group_desc_add_entries(desc, lock, n); kunmap_local(desc); mark_buffer_dirty(desc_bh); nilfs_mdt_mark_dirty(inode); brelse(desc_bh);
if (nfree == nilfs_palloc_entries_per_group(inode)) { ret = nilfs_palloc_delete_bitmap_block(inode, group); if (ret && ret != -ENOENT) nilfs_warn(inode->i_sb, "error %d deleting bitmap block of group=%lu, ino=%llu", ret, group, inode->i_ino); } } 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;}