diff options
| -rw-r--r-- | fs/nfs/getroot.c | 81 |
1 files changed, 27 insertions, 54 deletions
diff --git a/fs/nfs/getroot.c b/fs/nfs/getroot.c index 522e5ad4d8a..0ee43843f4e 100644 --- a/fs/nfs/getroot.c +++ b/fs/nfs/getroot.c @@ -43,6 +43,25 @@ #define NFSDBG_FACILITY NFSDBG_CLIENT /* + * Set the superblock root dentry. + * Note that this function frees the inode in case of error. + */ +static int nfs_superblock_set_dummy_root(struct super_block *sb, struct inode *inode) +{ + /* The mntroot acts as the dummy root dentry for this superblock */ + if (sb->s_root == NULL) { + sb->s_root = d_alloc_root(inode); + if (sb->s_root == NULL) { + iput(inode); + return -ENOMEM; + } + /* Circumvent igrab(): we know the inode is not being freed */ + atomic_inc(&inode->i_count); + } + return 0; +} + +/* * get an NFS2/NFS3 root dentry from the root filehandle */ struct dentry *nfs_get_root(struct super_block *sb, struct nfs_fh *mntfh) @@ -54,33 +73,6 @@ struct dentry *nfs_get_root(struct super_block *sb, struct nfs_fh *mntfh) struct inode *inode; int error; - /* create a dummy root dentry with dummy inode for this superblock */ - if (!sb->s_root) { - struct nfs_fh dummyfh; - struct dentry *root; - struct inode *iroot; - - memset(&dummyfh, 0, sizeof(dummyfh)); - memset(&fattr, 0, sizeof(fattr)); - nfs_fattr_init(&fattr); - fattr.valid = NFS_ATTR_FATTR; - fattr.type = NFDIR; - fattr.mode = S_IFDIR | S_IRUSR | S_IWUSR; - fattr.nlink = 2; - - iroot = nfs_fhget(sb, &dummyfh, &fattr); - if (IS_ERR(iroot)) - return ERR_PTR(PTR_ERR(iroot)); - - root = d_alloc_root(iroot); - if (!root) { - iput(iroot); - return ERR_PTR(-ENOMEM); - } - - sb->s_root = root; - } - /* get the actual root for this mount */ fsinfo.fattr = &fattr; @@ -96,6 +88,10 @@ struct dentry *nfs_get_root(struct super_block *sb, struct nfs_fh *mntfh) return ERR_PTR(PTR_ERR(inode)); } + error = nfs_superblock_set_dummy_root(sb, inode); + if (error != 0) + return ERR_PTR(error); + /* root dentries normally start off anonymous and get spliced in later * if the dentry tree reaches them; however if the dentry already * exists, we'll pick it up at this point and use it as the root @@ -241,33 +237,6 @@ struct dentry *nfs4_get_root(struct super_block *sb, struct nfs_fh *mntfh) dprintk("--> nfs4_get_root()\n"); - /* create a dummy root dentry with dummy inode for this superblock */ - if (!sb->s_root) { - struct nfs_fh dummyfh; - struct dentry *root; - struct inode *iroot; - - memset(&dummyfh, 0, sizeof(dummyfh)); - memset(&fattr, 0, sizeof(fattr)); - nfs_fattr_init(&fattr); - fattr.valid = NFS_ATTR_FATTR; - fattr.type = NFDIR; - fattr.mode = S_IFDIR | S_IRUSR | S_IWUSR; - fattr.nlink = 2; - - iroot = nfs_fhget(sb, &dummyfh, &fattr); - if (IS_ERR(iroot)) - return ERR_PTR(PTR_ERR(iroot)); - - root = d_alloc_root(iroot); - if (!root) { - iput(iroot); - return ERR_PTR(-ENOMEM); - } - - sb->s_root = root; - } - /* get the info about the server and filesystem */ error = nfs4_server_capabilities(server, mntfh); if (error < 0) { @@ -289,6 +258,10 @@ struct dentry *nfs4_get_root(struct super_block *sb, struct nfs_fh *mntfh) return ERR_PTR(PTR_ERR(inode)); } + error = nfs_superblock_set_dummy_root(sb, inode); + if (error != 0) + return ERR_PTR(error); + /* root dentries normally start off anonymous and get spliced in later * if the dentry tree reaches them; however if the dentry already * exists, we'll pick it up at this point and use it as the root |