From 8e6d782cab50884ba94324632700e6233a252f6a Mon Sep 17 00:00:00 2001 From: "J. Bruce Fields" Date: Tue, 20 Sep 2011 16:59:58 -0400 Subject: [PATCH] locks: break delegations on rename Cc: David Howells Acked-by: Jeff Layton Signed-off-by: J. Bruce Fields Signed-off-by: Al Viro --- .../lustre/include/linux/lustre_compat25.h | 4 +- .../staging/lustre/lustre/lvfs/lvfs_linux.c | 2 +- fs/cachefiles/namei.c | 2 +- fs/ecryptfs/inode.c | 3 +- fs/namei.c | 47 +++++++++++++++++-- fs/nfsd/vfs.c | 2 +- include/linux/fs.h | 2 +- 7 files changed, 51 insertions(+), 11 deletions(-) diff --git a/drivers/staging/lustre/lustre/include/linux/lustre_compat25.h b/drivers/staging/lustre/lustre/include/linux/lustre_compat25.h index 9243dfab43d3..80b019bf969c 100644 --- a/drivers/staging/lustre/lustre/include/linux/lustre_compat25.h +++ b/drivers/staging/lustre/lustre/include/linux/lustre_compat25.h @@ -105,8 +105,8 @@ static inline void ll_set_fs_pwd(struct fs_struct *fs, struct vfsmount *mnt, #define ll_vfs_unlink(inode,entry,mnt) vfs_unlink(inode,entry) #define ll_vfs_mknod(dir,entry,mnt,mode,dev) vfs_mknod(dir,entry,mode,dev) #define ll_security_inode_unlink(dir,entry,mnt) security_inode_unlink(dir,entry) -#define ll_vfs_rename(old,old_dir,mnt,new,new_dir,mnt1) \ - vfs_rename(old,old_dir,new,new_dir) +#define ll_vfs_rename(old,old_dir,mnt,new,new_dir,mnt1,delegated_inode) \ + vfs_rename(old,old_dir,new,new_dir,delegated_inode) #define cfs_bio_io_error(a,b) bio_io_error((a)) #define cfs_bio_endio(a,b,c) bio_endio((a),(c)) diff --git a/drivers/staging/lustre/lustre/lvfs/lvfs_linux.c b/drivers/staging/lustre/lustre/lvfs/lvfs_linux.c index 18e1b47a1d65..4ed7c9f0a8be 100644 --- a/drivers/staging/lustre/lustre/lvfs/lvfs_linux.c +++ b/drivers/staging/lustre/lustre/lvfs/lvfs_linux.c @@ -220,7 +220,7 @@ int lustre_rename(struct dentry *dir, struct vfsmount *mnt, GOTO(put_old, err = PTR_ERR(dchild_new)); err = ll_vfs_rename(dir->d_inode, dchild_old, mnt, - dir->d_inode, dchild_new, mnt); + dir->d_inode, dchild_new, mnt, NULL); dput(dchild_new); put_old: diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c index 31d480c0e046..ca65f39dc8dc 100644 --- a/fs/cachefiles/namei.c +++ b/fs/cachefiles/namei.c @@ -396,7 +396,7 @@ try_again: cachefiles_io_error(cache, "Rename security error %d", ret); } else { ret = vfs_rename(dir->d_inode, rep, - cache->graveyard->d_inode, grave); + cache->graveyard->d_inode, grave, NULL); if (ret != 0 && ret != -ENOMEM) cachefiles_io_error(cache, "Rename failed with error %d", ret); diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c index dc60b8bd09ec..c23b01bb7e04 100644 --- a/fs/ecryptfs/inode.c +++ b/fs/ecryptfs/inode.c @@ -640,7 +640,8 @@ ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry, goto out_lock; } rc = vfs_rename(lower_old_dir_dentry->d_inode, lower_old_dentry, - lower_new_dir_dentry->d_inode, lower_new_dentry); + lower_new_dir_dentry->d_inode, lower_new_dentry, + NULL); if (rc) goto out_lock; if (target_inode) diff --git a/fs/namei.c b/fs/namei.c index cfaeaae0f2db..ce7e580e4e14 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -4022,7 +4022,8 @@ out: } static int vfs_rename_other(struct inode *old_dir, struct dentry *old_dentry, - struct inode *new_dir, struct dentry *new_dentry) + struct inode *new_dir, struct dentry *new_dentry, + struct inode **delegated_inode) { struct inode *target = new_dentry->d_inode; struct inode *source = old_dentry->d_inode; @@ -4039,6 +4040,14 @@ static int vfs_rename_other(struct inode *old_dir, struct dentry *old_dentry, if (d_mountpoint(old_dentry)||d_mountpoint(new_dentry)) goto out; + error = try_break_deleg(source, delegated_inode); + if (error) + goto out; + if (target) { + error = try_break_deleg(target, delegated_inode); + if (error) + goto out; + } error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry); if (error) goto out; @@ -4053,8 +4062,30 @@ out: return error; } +/** + * vfs_rename - rename a filesystem object + * @old_dir: parent of source + * @old_dentry: source + * @new_dir: parent of destination + * @new_dentry: destination + * @delegated_inode: returns an inode needing a delegation break + * + * The caller must hold multiple mutexes--see lock_rename()). + * + * If vfs_rename discovers a delegation in need of breaking at either + * the source or destination, it will return -EWOULDBLOCK and return a + * reference to the inode in delegated_inode. The caller should then + * break the delegation and retry. Because breaking a delegation may + * take a long time, the caller should drop all locks before doing + * so. + * + * Alternatively, a caller may pass NULL for delegated_inode. This may + * be appropriate for callers that expect the underlying filesystem not + * to be NFS exported. + */ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry, - struct inode *new_dir, struct dentry *new_dentry) + struct inode *new_dir, struct dentry *new_dentry, + struct inode **delegated_inode) { int error; int is_dir = d_is_directory(old_dentry) || d_is_autodir(old_dentry); @@ -4082,7 +4113,7 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry, if (is_dir) error = vfs_rename_dir(old_dir,old_dentry,new_dir,new_dentry); else - error = vfs_rename_other(old_dir,old_dentry,new_dir,new_dentry); + error = vfs_rename_other(old_dir,old_dentry,new_dir,new_dentry,delegated_inode); if (!error) fsnotify_move(old_dir, new_dir, old_name, is_dir, new_dentry->d_inode, old_dentry); @@ -4098,6 +4129,7 @@ SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname, struct dentry *old_dentry, *new_dentry; struct dentry *trap; struct nameidata oldnd, newnd; + struct inode *delegated_inode = NULL; struct filename *from; struct filename *to; unsigned int lookup_flags = 0; @@ -4137,6 +4169,7 @@ retry: newnd.flags &= ~LOOKUP_PARENT; newnd.flags |= LOOKUP_RENAME_TARGET; +retry_deleg: trap = lock_rename(new_dir, old_dir); old_dentry = lookup_hash(&oldnd); @@ -4173,13 +4206,19 @@ retry: if (error) goto exit5; error = vfs_rename(old_dir->d_inode, old_dentry, - new_dir->d_inode, new_dentry); + new_dir->d_inode, new_dentry, + &delegated_inode); exit5: dput(new_dentry); exit4: dput(old_dentry); exit3: unlock_rename(new_dir, old_dir); + if (delegated_inode) { + error = break_deleg_wait(&delegated_inode); + if (!error) + goto retry_deleg; + } mnt_drop_write(oldnd.path.mnt); exit2: if (retry_estale(error, lookup_flags)) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 7a810235d599..45bf0295894d 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1837,7 +1837,7 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, if (host_err) goto out_dput_new; } - host_err = vfs_rename(fdir, odentry, tdir, ndentry); + host_err = vfs_rename(fdir, odentry, tdir, ndentry, NULL); if (!host_err) { host_err = commit_metadata(tfhp); if (!host_err) diff --git a/include/linux/fs.h b/include/linux/fs.h index 931f919f44e1..5bcff883fa90 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1456,7 +1456,7 @@ extern int vfs_symlink(struct inode *, struct dentry *, const char *); extern int vfs_link(struct dentry *, struct inode *, struct dentry *); extern int vfs_rmdir(struct inode *, struct dentry *); extern int vfs_unlink(struct inode *, struct dentry *, struct inode **); -extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *); +extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *, struct inode **); /* * VFS dentry helper functions.