diff options
author | Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> | 2010-04-12 01:46:02 +0900 |
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committer | Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> | 2010-05-10 11:32:31 +0900 |
commit | db55d92252c07c0e5561966ecca95c6f332dd892 (patch) | |
tree | 624aacfce2e287a89f4a49f03b543af3b5e4a6da | |
parent | fdce895ea5dd4e24edf1f4d693827349a4e5b3b4 (diff) | |
download | op-kernel-dev-db55d92252c07c0e5561966ecca95c6f332dd892.zip op-kernel-dev-db55d92252c07c0e5561966ecca95c6f332dd892.tar.gz |
nilfs2: add kernel doc comments to persistent object allocator functions
The implementation of persistent object allocator (alloc.c) is poorly
documented. This adds kernel doc style comments on that functions.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
-rw-r--r-- | fs/nilfs2/alloc.c | 154 | ||||
-rw-r--r-- | fs/nilfs2/alloc.h | 7 |
2 files changed, 160 insertions, 1 deletions
diff --git a/fs/nilfs2/alloc.c b/fs/nilfs2/alloc.c index 7cfb87e..d7fd696 100644 --- a/fs/nilfs2/alloc.c +++ b/fs/nilfs2/alloc.c @@ -31,6 +31,11 @@ #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) { @@ -38,12 +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); @@ -69,6 +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) { @@ -78,6 +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) { @@ -86,6 +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) { @@ -95,6 +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) @@ -107,6 +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, @@ -118,6 +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) { @@ -129,6 +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) { @@ -179,6 +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) @@ -191,6 +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) @@ -203,6 +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) { @@ -214,6 +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, @@ -223,6 +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) { @@ -235,11 +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; @@ -277,6 +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) @@ -287,6 +397,11 @@ nilfs_palloc_rest_groups_in_desc_block(const struct inode *inode, max - curr + 1); } +/** + * 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) { @@ -366,6 +481,11 @@ 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) { @@ -377,6 +497,11 @@ void nilfs_palloc_commit_alloc_entry(struct inode *inode, 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) { @@ -410,6 +535,11 @@ void nilfs_palloc_commit_free_entry(struct inode *inode, 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) { @@ -442,6 +572,11 @@ 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) { @@ -464,6 +599,11 @@ 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) { @@ -475,6 +615,12 @@ 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) { @@ -485,6 +631,12 @@ 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; diff --git a/fs/nilfs2/alloc.h b/fs/nilfs2/alloc.h index 5cccf87..9af34a7 100644 --- a/fs/nilfs2/alloc.h +++ b/fs/nilfs2/alloc.h @@ -29,6 +29,13 @@ #include <linux/buffer_head.h> #include <linux/fs.h> +/** + * nilfs_palloc_entries_per_group - get the number of entries per group + * @inode: inode of metadata file using this allocator + * + * The number of entries per group is defined by the number of bits + * that a bitmap block can maintain. + */ static inline unsigned long nilfs_palloc_entries_per_group(const struct inode *inode) { |