From ecaff756ff540f3821e2b00b8fa19aca07c7c3e5 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Sat, 16 Sep 2006 12:15:37 -0700 Subject: [PATCH] knfsd: Have ext2 reject file handles with bad inode numbers early This prevents bad inode numbers from triggering errors in ext2_get_inode. [akpm@osdl.org: speedup, cleanup] Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/ext2/super.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) (limited to 'fs/ext2') diff --git a/fs/ext2/super.c b/fs/ext2/super.c index 681dea8f9532..ca5bfb6914d2 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -251,6 +251,44 @@ static struct super_operations ext2_sops = { #endif }; +static struct dentry *ext2_get_dentry(struct super_block *sb, void *vobjp) +{ + __u32 *objp = vobjp; + unsigned long ino = objp[0]; + __u32 generation = objp[1]; + struct inode *inode; + struct dentry *result; + + if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO) + return ERR_PTR(-ESTALE); + if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count)) + return ERR_PTR(-ESTALE); + + /* iget isn't really right if the inode is currently unallocated!! + * ext2_read_inode currently does appropriate checks, but + * it might be "neater" to call ext2_get_inode first and check + * if the inode is valid..... + */ + inode = iget(sb, ino); + if (inode == NULL) + return ERR_PTR(-ENOMEM); + if (is_bad_inode(inode) || + (generation && inode->i_generation != generation)) { + /* we didn't find the right inode.. */ + iput(inode); + return ERR_PTR(-ESTALE); + } + /* now to find a dentry. + * If possible, get a well-connected one + */ + result = d_alloc_anon(inode); + if (!result) { + iput(inode); + return ERR_PTR(-ENOMEM); + } + return result; +} + /* Yes, most of these are left as NULL!! * A NULL value implies the default, which works with ext2-like file * systems, but can be improved upon. @@ -258,6 +296,7 @@ static struct super_operations ext2_sops = { */ static struct export_operations ext2_export_ops = { .get_parent = ext2_get_parent, + .get_dentry = ext2_get_dentry, }; static unsigned long get_sb_block(void **data) -- cgit v1.2.3 From 833f73299fdf4497af1552e219e95661f4d2cdca Mon Sep 17 00:00:00 2001 From: Dave Kleikamp Date: Mon, 18 Sep 2006 20:12:33 -0700 Subject: [PATCH] EXT2: Remove superblock lock contention in ext2_statfs Fix a performance degradation introduced in 2.6.17. (30% degradation running dbench with 16 threads) Commit 21730eed11de42f22afcbd43f450a1872a0b5ea1, which claims to make EXT2_DEBUG work again, moves the taking of the kernel lock out of debug-only code in ext2_count_free_inodes and ext2_count_free_blocks and into ext2_statfs. The same problem was fixed in ext3 by removing the lock completely (commit 5b11687924e40790deb0d5f959247ade82196665) Signed-off-by: Dave Kleikamp Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/ext2/balloc.c | 1 - fs/ext2/ialloc.c | 1 - fs/ext2/super.c | 2 -- 3 files changed, 4 deletions(-) (limited to 'fs/ext2') diff --git a/fs/ext2/balloc.c b/fs/ext2/balloc.c index d4870432ecfc..b1981d0e95ad 100644 --- a/fs/ext2/balloc.c +++ b/fs/ext2/balloc.c @@ -539,7 +539,6 @@ unsigned long ext2_count_free (struct buffer_head * map, unsigned int numchars) #endif /* EXT2FS_DEBUG */ -/* Superblock must be locked */ unsigned long ext2_count_free_blocks (struct super_block * sb) { struct ext2_group_desc * desc; diff --git a/fs/ext2/ialloc.c b/fs/ext2/ialloc.c index de85c61c58c5..695f69ccf908 100644 --- a/fs/ext2/ialloc.c +++ b/fs/ext2/ialloc.c @@ -637,7 +637,6 @@ fail: return ERR_PTR(err); } -/* Superblock must be locked */ unsigned long ext2_count_free_inodes (struct super_block * sb) { struct ext2_group_desc *desc; diff --git a/fs/ext2/super.c b/fs/ext2/super.c index ca5bfb6914d2..4286ff6330b6 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -1083,7 +1083,6 @@ static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) unsigned long overhead; int i; - lock_super(sb); if (test_opt (sb, MINIX_DF)) overhead = 0; else { @@ -1124,7 +1123,6 @@ static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf) buf->f_files = le32_to_cpu(sbi->s_es->s_inodes_count); buf->f_ffree = ext2_count_free_inodes (sb); buf->f_namelen = EXT2_NAME_LEN; - unlock_super(sb); return 0; } -- cgit v1.2.3