From: Vyacheslav Dubeyko <[email protected]> Subject: [PATCH] nilfs2: implement calculation of free inodes count
Currently, NILFS2 returns 0 as free inodes count (f_ffree) and current used inodes count as total file nodes in file system (f_files): df -i Filesystem Inodes IUsed IFree IUse% Mounted on /dev/loop0 2 2 0 100% /mnt/nilfs2 This patch implements real calculation of free inodes count. First of all, it is calculated total file nodes in file system as (desc_blocks_count * groups_per_desc_block * entries_per_group). Then, it is calculated free inodes count as difference the total file nodes and used inodes count. As a result, we have such output for NILFS2: df -i Filesystem Inodes IUsed IFree IUse% Mounted on /dev/loop0 4194304 2114701 2079603 51% /mnt/nilfs2 Reported-by: Clemens Eisserer <[email protected]> Signed-off-by: Vyacheslav Dubeyko <[email protected]> CC: Ryusuke Konishi <[email protected]> Tested-by: Vyacheslav Dubeyko <[email protected]> --- fs/nilfs2/alloc.c | 36 ++++++++------------------ fs/nilfs2/alloc.h | 24 ++++++++++++++++++ fs/nilfs2/ifile.c | 73 +++++++++++++++++++++++++++++++++++++++++++++++++++++ fs/nilfs2/ifile.h | 4 +++ fs/nilfs2/mdt.h | 2 ++ fs/nilfs2/super.c | 9 +++++-- 6 files changed, 120 insertions(+), 28 deletions(-) diff --git a/fs/nilfs2/alloc.c b/fs/nilfs2/alloc.c index eed4d7b..6c61ae9 100644 --- a/fs/nilfs2/alloc.c +++ b/fs/nilfs2/alloc.c @@ -30,29 +30,6 @@ #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 @@ -80,6 +57,13 @@ int nilfs_palloc_init_blockgroup(struct inode *inode, unsigned entry_size) mi->mi_blocks_per_group + 1; /* Number of blocks per descriptor including the descriptor block */ + atomic_set(&mi->mi_desc_blocks_count, 1); + /* + * The field mi_desc_blocks_count is used for + * storing knowledge about current count of + * desciptor blocks. Initially, it is initialized + * by one. + */ return 0; } @@ -246,9 +230,9 @@ static int nilfs_palloc_get_block(struct inode *inode, unsigned long blkoff, * @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) +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; diff --git a/fs/nilfs2/alloc.h b/fs/nilfs2/alloc.h index fb72381..073b571 100644 --- a/fs/nilfs2/alloc.h +++ b/fs/nilfs2/alloc.h @@ -30,6 +30,28 @@ #include <linux/fs.h> /** + * 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_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_entries_per_group - get the number of entries per group * @inode: inode of metadata file using this allocator * @@ -45,6 +67,8 @@ nilfs_palloc_entries_per_group(const struct inode *inode) int nilfs_palloc_init_blockgroup(struct inode *, unsigned); int nilfs_palloc_get_entry_block(struct inode *, __u64, int, struct buffer_head **); +int nilfs_palloc_get_desc_block(struct inode *, unsigned long, int, + struct buffer_head **); void *nilfs_palloc_block_get_entry(const struct inode *, __u64, const struct buffer_head *, void *); diff --git a/fs/nilfs2/ifile.c b/fs/nilfs2/ifile.c index d8e65bd..4f25549 100644 --- a/fs/nilfs2/ifile.c +++ b/fs/nilfs2/ifile.c @@ -160,6 +160,79 @@ int nilfs_ifile_get_inode_block(struct inode *ifile, ino_t ino, } /** + * nilfs_count_free_inodes - calculate free inodes count + * @root: root object + * @nmaxinodes: current maximum of available inodes count [out] + * @nfreeinodes: free inodes count [out] + */ +int nilfs_count_free_inodes(struct nilfs_root *root, + __statfs_word *nmaxinodes, + __statfs_word *nfreeinodes) +{ + struct inode *ifile; + struct buffer_head *desc_bh; + unsigned long groups_per_desc_block, entries_per_group; + unsigned long entries_per_desc_block; + unsigned long ngroups; + unsigned int desc_blocks; + __statfs_word nused, nmax; + unsigned long i; + int err = 0; + + BUG_ON(!root || !nfreeinodes || !nmaxinodes); + + ifile = root->ifile; + *nmaxinodes = 0; + *nfreeinodes = 0; + + ngroups = nilfs_palloc_groups_count(ifile); + groups_per_desc_block = nilfs_palloc_groups_per_desc_block(ifile); + entries_per_group = nilfs_palloc_entries_per_group(ifile); + nused = atomic_read(&root->inodes_count); + entries_per_desc_block = groups_per_desc_block * entries_per_group; + desc_blocks = + atomic_read(&NILFS_IFILE_I(ifile)->mi.mi_desc_blocks_count); + nmax = desc_blocks * entries_per_desc_block; + + if (nused >= nmax) { + for (i = groups_per_desc_block * (unsigned long)desc_blocks; + i < ngroups; + i += groups_per_desc_block) { + + err = nilfs_palloc_get_desc_block(ifile, i, 0, + &desc_bh); + if (err) + break; + else + desc_blocks++; + + brelse(desc_bh); + } + + nmax = entries_per_desc_block * desc_blocks; + + if (nused == nmax) { + desc_blocks++; + if ((desc_blocks * groups_per_desc_block) < ngroups) + nmax += entries_per_desc_block; + else + desc_blocks--; + } + + atomic_set(&NILFS_IFILE_I(ifile)->mi.mi_desc_blocks_count, + desc_blocks); + + if (nused > nmax) + return err ? err : -ERANGE; + } + + *nmaxinodes = nmax; + *nfreeinodes = nmax - nused; + + return 0; +} + +/** * nilfs_ifile_read - read or get ifile inode * @sb: super block instance * @root: root object diff --git a/fs/nilfs2/ifile.h b/fs/nilfs2/ifile.h index 59b6f2b..57a8564 100644 --- a/fs/nilfs2/ifile.h +++ b/fs/nilfs2/ifile.h @@ -27,6 +27,7 @@ #include <linux/fs.h> #include <linux/buffer_head.h> +#include <linux/statfs.h> #include <linux/nilfs2_fs.h> #include "mdt.h" #include "alloc.h" @@ -49,6 +50,9 @@ int nilfs_ifile_create_inode(struct inode *, ino_t *, struct buffer_head **); int nilfs_ifile_delete_inode(struct inode *, ino_t); int nilfs_ifile_get_inode_block(struct inode *, ino_t, struct buffer_head **); +int nilfs_count_free_inodes(struct nilfs_root *, + __statfs_word *, __statfs_word *); + int nilfs_ifile_read(struct super_block *sb, struct nilfs_root *root, size_t inode_size, struct nilfs_inode *raw_inode, struct inode **inodep); diff --git a/fs/nilfs2/mdt.h b/fs/nilfs2/mdt.h index ab172e8..c01b6fb 100644 --- a/fs/nilfs2/mdt.h +++ b/fs/nilfs2/mdt.h @@ -53,6 +53,7 @@ struct nilfs_shadow_map { * @mi_shadow: shadow of bmap and page caches * @mi_blocks_per_group: number of blocks in a group * @mi_blocks_per_desc_block: number of blocks per descriptor block + * @mi_desc_blocks_count: number of descriptor blocks */ struct nilfs_mdt_info { struct rw_semaphore mi_sem; @@ -64,6 +65,7 @@ struct nilfs_mdt_info { struct nilfs_shadow_map *mi_shadow; unsigned long mi_blocks_per_group; unsigned long mi_blocks_per_desc_block; + atomic_t mi_desc_blocks_count; }; static inline struct nilfs_mdt_info *NILFS_MDT(const struct inode *inode) diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c index c7d1f9f..548676b 100644 --- a/fs/nilfs2/super.c +++ b/fs/nilfs2/super.c @@ -609,6 +609,7 @@ static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf) unsigned long overhead; unsigned long nrsvblocks; sector_t nfreeblocks; + __statfs_word nmaxinodes, nfreeinodes; int err; /* @@ -633,14 +634,18 @@ static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf) if (unlikely(err)) return err; + err = nilfs_count_free_inodes(root, &nmaxinodes, &nfreeinodes); + if (unlikely(err)) + return err; + buf->f_type = NILFS_SUPER_MAGIC; buf->f_bsize = sb->s_blocksize; buf->f_blocks = blocks - overhead; buf->f_bfree = nfreeblocks; buf->f_bavail = (buf->f_bfree >= nrsvblocks) ? (buf->f_bfree - nrsvblocks) : 0; - buf->f_files = atomic_read(&root->inodes_count); - buf->f_ffree = 0; /* nilfs_count_free_inodes(sb); */ + buf->f_files = nmaxinodes; + buf->f_ffree = nfreeinodes; buf->f_namelen = NILFS_NAME_LEN; buf->f_fsid.val[0] = (u32)id; buf->f_fsid.val[1] = (u32)(id >> 32); -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
