diff options
Diffstat (limited to 'fs/nilfs2/alloc.c')
| -rw-r--r-- | fs/nilfs2/alloc.c | 246 |
1 files changed, 232 insertions, 14 deletions
diff --git a/fs/nilfs2/alloc.c b/fs/nilfs2/alloc.c index 3f959f1879d..741fd02e044 100644 --- a/fs/nilfs2/alloc.c +++ b/fs/nilfs2/alloc.c @@ -26,10 +26,16 @@ #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) { @@ -37,12 +43,21 @@ nilfs_palloc_groups_per_desc_block(const struct inode *inode) 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); @@ -68,6 +83,12 @@ int nilfs_palloc_init_blockgroup(struct inode *inode, unsigned entry_size) 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) { @@ -77,6 +98,14 @@ static unsigned long nilfs_palloc_group(const struct inode *inode, __u64 nr, 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) { @@ -85,6 +114,14 @@ nilfs_palloc_desc_blkoff(const struct inode *inode, unsigned long group) 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) { @@ -94,6 +131,12 @@ nilfs_palloc_bitmap_blkoff(const struct inode *inode, unsigned long group) 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) @@ -106,6 +149,13 @@ nilfs_palloc_group_desc_nfrees(struct inode *inode, unsigned long 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, @@ -117,6 +167,11 @@ nilfs_palloc_group_desc_add_entries(struct inode *inode, 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) { @@ -128,6 +183,12 @@ nilfs_palloc_entry_blkoff(const struct inode *inode, __u64 nr) 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) { @@ -178,6 +239,13 @@ static int nilfs_palloc_get_block(struct inode *inode, unsigned long blkoff, 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) @@ -190,6 +258,13 @@ static int nilfs_palloc_get_desc_block(struct inode *inode, 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) @@ -202,6 +277,13 @@ static int nilfs_palloc_get_bitmap_block(struct inode *inode, &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) { @@ -213,6 +295,13 @@ int nilfs_palloc_get_entry_block(struct inode *inode, __u64 nr, &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, @@ -222,6 +311,13 @@ nilfs_palloc_block_get_group_desc(const struct inode *inode, 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) { @@ -234,11 +330,19 @@ void *nilfs_palloc_block_get_entry(const struct inode *inode, __u64 nr, 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) /* size in bits */ + int bsize) { int curr, pos, end, i; @@ -276,6 +380,13 @@ static int nilfs_palloc_find_available_slot(struct inode *inode, 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) @@ -286,6 +397,74 @@ nilfs_palloc_rest_groups_in_desc_block(const struct inode *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) +{ + unsigned long blknum; + int ret; + + ret = nilfs_bmap_last_key(NILFS_I(inode)->i_bmap, &blknum); + if (likely(!ret)) + *desc_blocks = DIV_ROUND_UP( + 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) { @@ -365,17 +544,27 @@ int nilfs_palloc_prepare_alloc_entry(struct inode *inode, 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) { - nilfs_mdt_mark_buffer_dirty(req->pr_bitmap_bh); - nilfs_mdt_mark_buffer_dirty(req->pr_desc_bh); + 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) { @@ -395,20 +584,25 @@ void nilfs_palloc_commit_free_entry(struct inode *inode, group_offset, bitmap)) printk(KERN_WARNING "%s: entry number %llu already freed\n", __func__, (unsigned long long)req->pr_entry_nr); - - nilfs_palloc_group_desc_add_entries(inode, group, desc, 1); + 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); - nilfs_mdt_mark_buffer_dirty(req->pr_desc_bh); - nilfs_mdt_mark_buffer_dirty(req->pr_bitmap_bh); + 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) { @@ -425,10 +619,10 @@ void nilfs_palloc_abort_alloc_entry(struct inode *inode, 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 numer %llu already freed\n", + printk(KERN_WARNING "%s: entry number %llu already freed\n", __func__, (unsigned long long)req->pr_entry_nr); - - nilfs_palloc_group_desc_add_entries(inode, group, desc, 1); + 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); @@ -441,6 +635,11 @@ void nilfs_palloc_abort_alloc_entry(struct inode *inode, 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) { @@ -463,6 +662,11 @@ int nilfs_palloc_prepare_free_entry(struct inode *inode, 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) { @@ -474,6 +678,12 @@ void nilfs_palloc_abort_free_entry(struct inode *inode, 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) { @@ -484,6 +694,12 @@ nilfs_palloc_group_is_in(struct inode *inode, unsigned long group, __u64 nr) 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; @@ -493,7 +709,7 @@ int nilfs_palloc_freev(struct inode *inode, __u64 *entry_nrs, size_t nitems) unsigned long group, group_offset; int i, j, n, ret; - for (i = 0; i < nitems; i += n) { + 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) @@ -512,7 +728,7 @@ int nilfs_palloc_freev(struct inode *inode, __u64 *entry_nrs, size_t nitems) for (j = i, n = 0; (j < nitems) && nilfs_palloc_group_is_in(inode, group, entry_nrs[j]); - j++, n++) { + j++) { nilfs_palloc_group(inode, entry_nrs[j], &group_offset); if (!nilfs_clear_bit_atomic( nilfs_mdt_bgl_lock(inode, group), @@ -521,6 +737,8 @@ int nilfs_palloc_freev(struct inode *inode, __u64 *entry_nrs, size_t nitems) "%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); @@ -528,8 +746,8 @@ int nilfs_palloc_freev(struct inode *inode, __u64 *entry_nrs, size_t nitems) kunmap(bitmap_bh->b_page); kunmap(desc_bh->b_page); - nilfs_mdt_mark_buffer_dirty(desc_bh); - nilfs_mdt_mark_buffer_dirty(bitmap_bh); + mark_buffer_dirty(desc_bh); + mark_buffer_dirty(bitmap_bh); nilfs_mdt_mark_dirty(inode); brelse(bitmap_bh); |