From 8044f7f468469c80031611206d554f86fcdfe704 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 22 Apr 2010 12:09:48 +0200 Subject: cifs: add bdi backing to mount session This ensures that dirty data gets flushed properly. Signed-off-by: Jens Axboe --- fs/cifs/cifs_fs_sb.h | 3 +++ fs/cifs/cifsfs.c | 10 ++++++++++ 2 files changed, 13 insertions(+) (limited to 'fs/cifs') diff --git a/fs/cifs/cifs_fs_sb.h b/fs/cifs/cifs_fs_sb.h index 4797787c6a44..246a167cb913 100644 --- a/fs/cifs/cifs_fs_sb.h +++ b/fs/cifs/cifs_fs_sb.h @@ -18,6 +18,8 @@ #ifndef _CIFS_FS_SB_H #define _CIFS_FS_SB_H +#include + #define CIFS_MOUNT_NO_PERM 1 /* do not do client vfs_perm check */ #define CIFS_MOUNT_SET_UID 2 /* set current's euid in create etc. */ #define CIFS_MOUNT_SERVER_INUM 4 /* inode numbers from uniqueid from server */ @@ -50,5 +52,6 @@ struct cifs_sb_info { #ifdef CONFIG_CIFS_DFS_UPCALL char *mountdata; /* mount options received at mount time */ #endif + struct backing_dev_info bdi; }; #endif /* _CIFS_FS_SB_H */ diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index ded66be6597c..ad235d604a0b 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -103,6 +103,12 @@ cifs_read_super(struct super_block *sb, void *data, if (cifs_sb == NULL) return -ENOMEM; + rc = bdi_setup_and_register(&cifs_sb->bdi, "cifs", BDI_CAP_MAP_COPY); + if (rc) { + kfree(cifs_sb); + return rc; + } + #ifdef CONFIG_CIFS_DFS_UPCALL /* copy mount params to sb for use in submounts */ /* BB: should we move this after the mount so we @@ -115,6 +121,7 @@ cifs_read_super(struct super_block *sb, void *data, int len = strlen(data); cifs_sb->mountdata = kzalloc(len + 1, GFP_KERNEL); if (cifs_sb->mountdata == NULL) { + bdi_destroy(&cifs_sb->bdi); kfree(sb->s_fs_info); sb->s_fs_info = NULL; return -ENOMEM; @@ -135,6 +142,7 @@ cifs_read_super(struct super_block *sb, void *data, sb->s_magic = CIFS_MAGIC_NUMBER; sb->s_op = &cifs_super_ops; + sb->s_bdi = &cifs_sb->bdi; /* if (cifs_sb->tcon->ses->server->maxBuf > MAX_CIFS_HDR_SIZE + 512) sb->s_blocksize = cifs_sb->tcon->ses->server->maxBuf - MAX_CIFS_HDR_SIZE; */ @@ -183,6 +191,7 @@ out_mount_failed: } #endif unload_nls(cifs_sb->local_nls); + bdi_destroy(&cifs_sb->bdi); kfree(cifs_sb); } return rc; @@ -214,6 +223,7 @@ cifs_put_super(struct super_block *sb) #endif unload_nls(cifs_sb->local_nls); + bdi_destroy(&cifs_sb->bdi); kfree(cifs_sb); unlock_kernel(); -- cgit v1.2.3 From 3d69438031b00c601c991ab447cafb7d5c3c59a6 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Tue, 11 May 2010 14:59:55 -0400 Subject: cifs: guard against hardlinking directories When we made serverino the default, we trusted that the field sent by the server in the "uniqueid" field was actually unique. It turns out that it isn't reliably so. Samba, in particular, will just put the st_ino in the uniqueid field when unix extensions are enabled. When a share spans multiple filesystems, it's quite possible that there will be collisions. This is a server bug, but when the inodes in question are a directory (as is often the case) and there is a collision with the root inode of the mount, the result is a kernel panic on umount. Fix this by checking explicitly for directory inodes with the same uniqueid. If that is the case, then we can assume that using server inode numbers will be a problem and that they should be disabled. Fixes Samba bugzilla 7407 Signed-off-by: Jeff Layton CC: Stable Reviewed-and-Tested-by: Suresh Jayaraman Signed-off-by: Steve French --- fs/cifs/cifsglob.h | 1 + fs/cifs/inode.c | 21 +++++++++++++++++++-- 2 files changed, 20 insertions(+), 2 deletions(-) (limited to 'fs/cifs') diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index ecf0ffbe2b64..0c2fd17439c8 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -502,6 +502,7 @@ struct dfs_info3_param { #define CIFS_FATTR_DFS_REFERRAL 0x1 #define CIFS_FATTR_DELETE_PENDING 0x2 #define CIFS_FATTR_NEED_REVAL 0x4 +#define CIFS_FATTR_INO_COLLISION 0x8 struct cifs_fattr { u32 cf_flags; diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c index 35ec11716213..29b9ea244c81 100644 --- a/fs/cifs/inode.c +++ b/fs/cifs/inode.c @@ -715,6 +715,16 @@ cifs_find_inode(struct inode *inode, void *opaque) if (CIFS_I(inode)->uniqueid != fattr->cf_uniqueid) return 0; + /* + * uh oh -- it's a directory. We can't use it since hardlinked dirs are + * verboten. Disable serverino and return it as if it were found, the + * caller can discard it, generate a uniqueid and retry the find + */ + if (S_ISDIR(inode->i_mode) && !list_empty(&inode->i_dentry)) { + fattr->cf_flags |= CIFS_FATTR_INO_COLLISION; + cifs_autodisable_serverino(CIFS_SB(inode->i_sb)); + } + return 1; } @@ -734,15 +744,22 @@ cifs_iget(struct super_block *sb, struct cifs_fattr *fattr) unsigned long hash; struct inode *inode; +retry_iget5_locked: cFYI(1, ("looking for uniqueid=%llu", fattr->cf_uniqueid)); /* hash down to 32-bits on 32-bit arch */ hash = cifs_uniqueid_to_ino_t(fattr->cf_uniqueid); inode = iget5_locked(sb, hash, cifs_find_inode, cifs_init_inode, fattr); - - /* we have fattrs in hand, update the inode */ if (inode) { + /* was there a problematic inode number collision? */ + if (fattr->cf_flags & CIFS_FATTR_INO_COLLISION) { + iput(inode); + fattr->cf_uniqueid = iunique(sb, ROOT_I); + fattr->cf_flags &= ~CIFS_FATTR_INO_COLLISION; + goto retry_iget5_locked; + } + cifs_fattr_to_inode(inode, fattr); if (sb->s_flags & MS_NOATIME) inode->i_flags |= S_NOATIME | S_NOCMTIME; -- cgit v1.2.3