From 9a53c3a783c2fa9b969628e65695c11c3e51e673 Mon Sep 17 00:00:00 2001 From: Dave Hansen Date: Sat, 30 Sep 2006 23:29:03 -0700 Subject: [PATCH] r/o bind mounts: unlink: monitor i_nlink When a filesystem decrements i_nlink to zero, it means that a write must be performed in order to drop the inode from the filesystem. We're shortly going to have keep filesystems from being remounted r/o between the time that this i_nlink decrement and that write occurs. So, add a little helper function to do the decrements. We'll tie into it in a bit to note when i_nlink hits zero. Signed-off-by: Dave Hansen Acked-by: Christoph Hellwig Cc: Al Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/hpfs/namei.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'fs/hpfs/namei.c') diff --git a/fs/hpfs/namei.c b/fs/hpfs/namei.c index 59e7dc182a0..4078b0becc5 100644 --- a/fs/hpfs/namei.c +++ b/fs/hpfs/namei.c @@ -434,7 +434,7 @@ again: unlock_kernel(); return -ENOSPC; default: - inode->i_nlink--; + drop_nlink(inode); err = 0; } goto out; @@ -494,7 +494,7 @@ static int hpfs_rmdir(struct inode *dir, struct dentry *dentry) err = -ENOSPC; break; default: - dir->i_nlink--; + drop_nlink(dir); inode->i_nlink = 0; err = 0; } @@ -636,7 +636,7 @@ static int hpfs_rename(struct inode *old_dir, struct dentry *old_dentry, hpfs_i(i)->i_parent_dir = new_dir->i_ino; if (S_ISDIR(i->i_mode)) { new_dir->i_nlink++; - old_dir->i_nlink--; + drop_nlink(old_dir); } if ((fnode = hpfs_map_fnode(i->i_sb, i->i_ino, &bh))) { fnode->up = new_dir->i_ino; -- cgit v1.2.3 From d8c76e6f45c111c32a4b3e50a2adc9210737b0d8 Mon Sep 17 00:00:00 2001 From: Dave Hansen Date: Sat, 30 Sep 2006 23:29:04 -0700 Subject: [PATCH] r/o bind mount prepwork: inc_nlink() helper This is mostly included for parity with dec_nlink(), where we will have some more hooks. This one should stay pretty darn straightforward for now. Signed-off-by: Dave Hansen Acked-by: Christoph Hellwig Cc: Al Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/hpfs/namei.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/hpfs/namei.c') diff --git a/fs/hpfs/namei.c b/fs/hpfs/namei.c index 4078b0becc5..25dd6f81eca 100644 --- a/fs/hpfs/namei.c +++ b/fs/hpfs/namei.c @@ -89,7 +89,7 @@ static int hpfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) brelse(bh); hpfs_mark_4buffers_dirty(&qbh0); hpfs_brelse4(&qbh0); - dir->i_nlink++; + inc_nlink(dir); insert_inode_hash(result); if (result->i_uid != current->fsuid || @@ -635,7 +635,7 @@ static int hpfs_rename(struct inode *old_dir, struct dentry *old_dentry, end: hpfs_i(i)->i_parent_dir = new_dir->i_ino; if (S_ISDIR(i->i_mode)) { - new_dir->i_nlink++; + inc_nlink(new_dir); drop_nlink(old_dir); } if ((fnode = hpfs_map_fnode(i->i_sb, i->i_ino, &bh))) { -- cgit v1.2.3 From ce71ec36840368b877fb63bd14c8e67ab62d08b1 Mon Sep 17 00:00:00 2001 From: Dave Hansen Date: Sat, 30 Sep 2006 23:29:06 -0700 Subject: [PATCH] r/o bind mounts: monitor zeroing of i_nlink Some filesystems, instead of simply decrementing i_nlink, simply zero it during an unlink operation. We need to catch these in addition to the decrement operations. Signed-off-by: Dave Hansen Acked-by: Christoph Hellwig Cc: Al Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/hpfs/namei.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/hpfs/namei.c') diff --git a/fs/hpfs/namei.c b/fs/hpfs/namei.c index 25dd6f81eca..2507e7393f3 100644 --- a/fs/hpfs/namei.c +++ b/fs/hpfs/namei.c @@ -495,7 +495,7 @@ static int hpfs_rmdir(struct inode *dir, struct dentry *dentry) break; default: drop_nlink(dir); - inode->i_nlink = 0; + clear_nlink(inode); err = 0; } goto out; @@ -590,7 +590,7 @@ static int hpfs_rename(struct inode *old_dir, struct dentry *old_dentry, int r; if ((r = hpfs_remove_dirent(old_dir, dno, dep, &qbh, 1)) != 2) { if ((nde = map_dirent(new_dir, hpfs_i(new_dir)->i_dno, (char *)new_name, new_len, NULL, &qbh1))) { - new_inode->i_nlink = 0; + clear_nlink(new_inode); copy_de(nde, &de); memcpy(nde->name, new_name, new_len); hpfs_mark_4buffers_dirty(&qbh1); -- cgit v1.2.3