diff options
Diffstat (limited to 'fs/9p')
-rw-r--r-- | fs/9p/cache.c | 14 | ||||
-rw-r--r-- | fs/9p/fid.c | 2 | ||||
-rw-r--r-- | fs/9p/v9fs.c | 41 | ||||
-rw-r--r-- | fs/9p/v9fs.h | 23 | ||||
-rw-r--r-- | fs/9p/v9fs_vfs.h | 1 | ||||
-rw-r--r-- | fs/9p/vfs_dir.c | 102 | ||||
-rw-r--r-- | fs/9p/vfs_file.c | 27 | ||||
-rw-r--r-- | fs/9p/vfs_inode.c | 96 | ||||
-rw-r--r-- | fs/9p/vfs_super.c | 3 |
9 files changed, 181 insertions, 128 deletions
diff --git a/fs/9p/cache.c b/fs/9p/cache.c index 51c94e26a34..e777961939f 100644 --- a/fs/9p/cache.c +++ b/fs/9p/cache.c @@ -343,18 +343,7 @@ int __v9fs_fscache_release_page(struct page *page, gfp_t gfp) BUG_ON(!vcookie->fscache); - if (PageFsCache(page)) { - if (fscache_check_page_write(vcookie->fscache, page)) { - if (!(gfp & __GFP_WAIT)) - return 0; - fscache_wait_on_page_write(vcookie->fscache, page); - } - - fscache_uncache_page(vcookie->fscache, page); - ClearPageFsCache(page); - } - - return 1; + return fscache_maybe_release_page(vcookie->fscache, page, gfp); } void __v9fs_fscache_invalidate_page(struct page *page) @@ -368,7 +357,6 @@ void __v9fs_fscache_invalidate_page(struct page *page) fscache_wait_on_page_write(vcookie->fscache, page); BUG_ON(!PageLocked(page)); fscache_uncache_page(vcookie->fscache, page); - ClearPageFsCache(page); } } diff --git a/fs/9p/fid.c b/fs/9p/fid.c index 14d94420457..08b2eb15704 100644 --- a/fs/9p/fid.c +++ b/fs/9p/fid.c @@ -151,7 +151,7 @@ struct p9_fid *v9fs_fid_lookup(struct dentry *dentry) if (access == V9FS_ACCESS_SINGLE) return ERR_PTR(-EPERM); - if (v9fs_extended(v9ses)) + if (v9fs_proto_dotu(v9ses)) uname = NULL; else uname = v9ses->uname; diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c index cf62b05e296..6c7f6a25111 100644 --- a/fs/9p/v9fs.c +++ b/fs/9p/v9fs.c @@ -84,7 +84,7 @@ static const match_table_t tokens = { static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts) { - char *options; + char *options, *tmp_options; substring_t args[MAX_OPT_ARGS]; char *p; int option = 0; @@ -102,9 +102,12 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts) if (!opts) return 0; - options = kstrdup(opts, GFP_KERNEL); - if (!options) + tmp_options = kstrdup(opts, GFP_KERNEL); + if (!tmp_options) { + ret = -ENOMEM; goto fail_option_alloc; + } + options = tmp_options; while ((p = strsep(&options, ",")) != NULL) { int token; @@ -159,8 +162,12 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts) break; case Opt_cache: s = match_strdup(&args[0]); - if (!s) - goto fail_option_alloc; + if (!s) { + ret = -ENOMEM; + P9_DPRINTK(P9_DEBUG_ERROR, + "problem allocating copy of cache arg\n"); + goto free_and_return; + } if (strcmp(s, "loose") == 0) v9ses->cache = CACHE_LOOSE; @@ -173,8 +180,12 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts) case Opt_access: s = match_strdup(&args[0]); - if (!s) - goto fail_option_alloc; + if (!s) { + ret = -ENOMEM; + P9_DPRINTK(P9_DEBUG_ERROR, + "problem allocating copy of access arg\n"); + goto free_and_return; + } v9ses->flags &= ~V9FS_ACCESS_MASK; if (strcmp(s, "user") == 0) @@ -194,13 +205,11 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts) continue; } } - kfree(options); - return ret; +free_and_return: + kfree(tmp_options); fail_option_alloc: - P9_DPRINTK(P9_DEBUG_ERROR, - "failed to allocate copy of option argument\n"); - return -ENOMEM; + return ret; } /** @@ -232,7 +241,7 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses, list_add(&v9ses->slist, &v9fs_sessionlist); spin_unlock(&v9fs_sessionlist_lock); - v9ses->flags = V9FS_EXTENDED | V9FS_ACCESS_USER; + v9ses->flags = V9FS_PROTO_2000U | V9FS_ACCESS_USER; strcpy(v9ses->uname, V9FS_DEFUSER); strcpy(v9ses->aname, V9FS_DEFANAME); v9ses->uid = ~0; @@ -253,13 +262,13 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses, goto error; } - if (!v9ses->clnt->dotu) - v9ses->flags &= ~V9FS_EXTENDED; + if (!p9_is_proto_dotu(v9ses->clnt)) + v9ses->flags &= ~V9FS_PROTO_2000U; v9ses->maxdata = v9ses->clnt->msize - P9_IOHDRSZ; /* for legacy mode, fall back to V9FS_ACCESS_ANY */ - if (!v9fs_extended(v9ses) && + if (!v9fs_proto_dotu(v9ses) && ((v9ses->flags&V9FS_ACCESS_MASK) == V9FS_ACCESS_USER)) { v9ses->flags &= ~V9FS_ACCESS_MASK; diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h index 019f4ccb70c..6b801d1ddf4 100644 --- a/fs/9p/v9fs.h +++ b/fs/9p/v9fs.h @@ -23,7 +23,8 @@ /** * enum p9_session_flags - option flags for each 9P session - * @V9FS_EXTENDED: whether or not to use 9P2000.u extensions + * @V9FS_PROTO_2000U: whether or not to use 9P2000.u extensions + * @V9FS_PROTO_2000L: whether or not to use 9P2000.l extensions * @V9FS_ACCESS_SINGLE: only the mounting user can access the hierarchy * @V9FS_ACCESS_USER: a new attach will be issued for every user (default) * @V9FS_ACCESS_ANY: use a single attach for all users @@ -32,11 +33,12 @@ * Session flags reflect options selected by users at mount time */ enum p9_session_flags { - V9FS_EXTENDED = 0x01, - V9FS_ACCESS_SINGLE = 0x02, - V9FS_ACCESS_USER = 0x04, - V9FS_ACCESS_ANY = 0x06, - V9FS_ACCESS_MASK = 0x06, + V9FS_PROTO_2000U = 0x01, + V9FS_PROTO_2000L = 0x02, + V9FS_ACCESS_SINGLE = 0x04, + V9FS_ACCESS_USER = 0x08, + V9FS_ACCESS_ANY = 0x0C, + V9FS_ACCESS_MASK = 0x0C, }; /* possible values of ->cache */ @@ -121,7 +123,12 @@ static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode) return (inode->i_sb->s_fs_info); } -static inline int v9fs_extended(struct v9fs_session_info *v9ses) +static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses) { - return v9ses->flags & V9FS_EXTENDED; + return v9ses->flags & V9FS_PROTO_2000U; +} + +static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses) +{ + return v9ses->flags & V9FS_PROTO_2000L; } diff --git a/fs/9p/v9fs_vfs.h b/fs/9p/v9fs_vfs.h index 3a7560e3586..ed835836e0d 100644 --- a/fs/9p/v9fs_vfs.h +++ b/fs/9p/v9fs_vfs.h @@ -60,3 +60,4 @@ void v9fs_dentry_release(struct dentry *); int v9fs_uflags2omode(int uflags, int extended); ssize_t v9fs_file_readn(struct file *, char *, char __user *, u32, u64); +void v9fs_blank_wstat(struct p9_wstat *wstat); diff --git a/fs/9p/vfs_dir.c b/fs/9p/vfs_dir.c index 873cd31baa4..d8a3afe4ff7 100644 --- a/fs/9p/vfs_dir.c +++ b/fs/9p/vfs_dir.c @@ -40,6 +40,24 @@ #include "fid.h" /** + * struct p9_rdir - readdir accounting + * @mutex: mutex protecting readdir + * @head: start offset of current dirread buffer + * @tail: end offset of current dirread buffer + * @buf: dirread buffer + * + * private structure for keeping track of readdir + * allocated on demand + */ + +struct p9_rdir { + struct mutex mutex; + int head; + int tail; + uint8_t *buf; +}; + +/** * dt_type - return file type * @mistat: mistat structure * @@ -58,6 +76,15 @@ static inline int dt_type(struct p9_wstat *mistat) return rettype; } +static void p9stat_init(struct p9_wstat *stbuf) +{ + stbuf->name = NULL; + stbuf->uid = NULL; + stbuf->gid = NULL; + stbuf->muid = NULL; + stbuf->extension = NULL; +} + /** * v9fs_dir_readdir - read a directory * @filp: opened file structure @@ -70,56 +97,79 @@ static int v9fs_dir_readdir(struct file *filp, void *dirent, filldir_t filldir) { int over; struct p9_wstat st; - int err; + int err = 0; struct p9_fid *fid; int buflen; - char *statbuf; - int n, i = 0; + int reclen = 0; + struct p9_rdir *rdir; P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", filp->f_path.dentry->d_name.name); fid = filp->private_data; buflen = fid->clnt->msize - P9_IOHDRSZ; - statbuf = kmalloc(buflen, GFP_KERNEL); - if (!statbuf) - return -ENOMEM; - - while (1) { - err = v9fs_file_readn(filp, statbuf, NULL, buflen, - fid->rdir_fpos); - if (err <= 0) - break; - - n = err; - while (i < n) { - err = p9stat_read(statbuf + i, buflen-i, &st, - fid->clnt->dotu); + + /* allocate rdir on demand */ + if (!fid->rdir) { + rdir = kmalloc(sizeof(struct p9_rdir) + buflen, GFP_KERNEL); + + if (rdir == NULL) { + err = -ENOMEM; + goto exit; + } + spin_lock(&filp->f_dentry->d_lock); + if (!fid->rdir) { + rdir->buf = (uint8_t *)rdir + sizeof(struct p9_rdir); + mutex_init(&rdir->mutex); + rdir->head = rdir->tail = 0; + fid->rdir = (void *) rdir; + rdir = NULL; + } + spin_unlock(&filp->f_dentry->d_lock); + kfree(rdir); + } + rdir = (struct p9_rdir *) fid->rdir; + + err = mutex_lock_interruptible(&rdir->mutex); + while (err == 0) { + if (rdir->tail == rdir->head) { + err = v9fs_file_readn(filp, rdir->buf, NULL, + buflen, filp->f_pos); + if (err <= 0) + goto unlock_and_exit; + + rdir->head = 0; + rdir->tail = err; + } + while (rdir->head < rdir->tail) { + p9stat_init(&st); + err = p9stat_read(rdir->buf + rdir->head, + buflen - rdir->head, &st, + fid->clnt->proto_version); if (err) { P9_DPRINTK(P9_DEBUG_VFS, "returned %d\n", err); err = -EIO; p9stat_free(&st); - goto free_and_exit; + goto unlock_and_exit; } - - i += st.size+2; - fid->rdir_fpos += st.size+2; + reclen = st.size+2; over = filldir(dirent, st.name, strlen(st.name), filp->f_pos, v9fs_qid2ino(&st.qid), dt_type(&st)); - filp->f_pos += st.size+2; - p9stat_free(&st); if (over) { err = 0; - goto free_and_exit; + goto unlock_and_exit; } + rdir->head += reclen; + filp->f_pos += reclen; } } -free_and_exit: - kfree(statbuf); +unlock_and_exit: + mutex_unlock(&rdir->mutex); +exit: return err; } diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c index 3902bf43a08..df52d488d2a 100644 --- a/fs/9p/vfs_file.c +++ b/fs/9p/vfs_file.c @@ -61,7 +61,7 @@ int v9fs_file_open(struct inode *inode, struct file *file) P9_DPRINTK(P9_DEBUG_VFS, "inode: %p file: %p \n", inode, file); v9ses = v9fs_inode2v9ses(inode); - omode = v9fs_uflags2omode(file->f_flags, v9fs_extended(v9ses)); + omode = v9fs_uflags2omode(file->f_flags, v9fs_proto_dotu(v9ses)); fid = file->private_data; if (!fid) { fid = v9fs_fid_clone(file->f_path.dentry); @@ -77,7 +77,7 @@ int v9fs_file_open(struct inode *inode, struct file *file) i_size_write(inode, 0); inode->i_blocks = 0; } - if ((file->f_flags & O_APPEND) && (!v9fs_extended(v9ses))) + if ((file->f_flags & O_APPEND) && (!v9fs_proto_dotu(v9ses))) generic_file_llseek(file, 0, SEEK_END); } @@ -114,7 +114,7 @@ static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl) P9_DPRINTK(P9_DEBUG_VFS, "filp: %p lock: %p\n", filp, fl); /* No mandatory locks */ - if (__mandatory_lock(inode)) + if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK) return -ENOLCK; if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) { @@ -215,7 +215,7 @@ v9fs_file_write(struct file *filp, const char __user * data, struct p9_fid *fid; struct p9_client *clnt; struct inode *inode = filp->f_path.dentry->d_inode; - int origin = *offset; + loff_t origin = *offset; unsigned long pg_start, pg_end; P9_DPRINTK(P9_DEBUG_VFS, "data %p count %d offset %x\n", data, @@ -257,6 +257,23 @@ v9fs_file_write(struct file *filp, const char __user * data, return total; } +static int v9fs_file_fsync(struct file *filp, struct dentry *dentry, + int datasync) +{ + struct p9_fid *fid; + struct p9_wstat wstat; + int retval; + + P9_DPRINTK(P9_DEBUG_VFS, "filp %p dentry %p datasync %x\n", filp, + dentry, datasync); + + fid = filp->private_data; + v9fs_blank_wstat(&wstat); + + retval = p9_client_wstat(fid, &wstat); + return retval; +} + static const struct file_operations v9fs_cached_file_operations = { .llseek = generic_file_llseek, .read = do_sync_read, @@ -266,6 +283,7 @@ static const struct file_operations v9fs_cached_file_operations = { .release = v9fs_dir_release, .lock = v9fs_file_lock, .mmap = generic_file_readonly_mmap, + .fsync = v9fs_file_fsync, }; const struct file_operations v9fs_file_operations = { @@ -276,4 +294,5 @@ const struct file_operations v9fs_file_operations = { .release = v9fs_dir_release, .lock = v9fs_file_lock, .mmap = generic_file_readonly_mmap, + .fsync = v9fs_file_fsync, }; diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c index 5947628aefe..5fe45d692c9 100644 --- a/fs/9p/vfs_inode.c +++ b/fs/9p/vfs_inode.c @@ -60,7 +60,7 @@ static int unixmode2p9mode(struct v9fs_session_info *v9ses, int mode) res = mode & 0777; if (S_ISDIR(mode)) res |= P9_DMDIR; - if (v9fs_extended(v9ses)) { + if (v9fs_proto_dotu(v9ses)) { if (S_ISLNK(mode)) res |= P9_DMSYMLINK; if (v9ses->nodev == 0) { @@ -102,21 +102,21 @@ static int p9mode2unixmode(struct v9fs_session_info *v9ses, int mode) if ((mode & P9_DMDIR) == P9_DMDIR) res |= S_IFDIR; - else if ((mode & P9_DMSYMLINK) && (v9fs_extended(v9ses))) + else if ((mode & P9_DMSYMLINK) && (v9fs_proto_dotu(v9ses))) res |= S_IFLNK; - else if ((mode & P9_DMSOCKET) && (v9fs_extended(v9ses)) + else if ((mode & P9_DMSOCKET) && (v9fs_proto_dotu(v9ses)) && (v9ses->nodev == 0)) res |= S_IFSOCK; - else if ((mode & P9_DMNAMEDPIPE) && (v9fs_extended(v9ses)) + else if ((mode & P9_DMNAMEDPIPE) && (v9fs_proto_dotu(v9ses)) && (v9ses->nodev == 0)) res |= S_IFIFO; - else if ((mode & P9_DMDEVICE) && (v9fs_extended(v9ses)) + else if ((mode & P9_DMDEVICE) && (v9fs_proto_dotu(v9ses)) && (v9ses->nodev == 0)) res |= S_IFBLK; else res |= S_IFREG; - if (v9fs_extended(v9ses)) { + if (v9fs_proto_dotu(v9ses)) { if ((mode & P9_DMSETUID) == P9_DMSETUID) res |= S_ISUID; @@ -176,7 +176,7 @@ int v9fs_uflags2omode(int uflags, int extended) * */ -static void +void v9fs_blank_wstat(struct p9_wstat *wstat) { wstat->type = ~0; @@ -265,7 +265,7 @@ struct inode *v9fs_get_inode(struct super_block *sb, int mode) case S_IFBLK: case S_IFCHR: case S_IFSOCK: - if (!v9fs_extended(v9ses)) { + if (!v9fs_proto_dotu(v9ses)) { P9_DPRINTK(P9_DEBUG_ERROR, "special files without extended mode\n"); err = -EINVAL; @@ -278,7 +278,7 @@ struct inode *v9fs_get_inode(struct super_block *sb, int mode) inode->i_fop = &v9fs_file_operations; break; case S_IFLNK: - if (!v9fs_extended(v9ses)) { + if (!v9fs_proto_dotu(v9ses)) { P9_DPRINTK(P9_DEBUG_ERROR, "extended modes used w/o 9P2000.u\n"); err = -EINVAL; @@ -288,7 +288,7 @@ struct inode *v9fs_get_inode(struct super_block *sb, int mode) break; case S_IFDIR: inc_nlink(inode); - if (v9fs_extended(v9ses)) + if (v9fs_proto_dotu(v9ses)) inode->i_op = &v9fs_dir_inode_operations_ext; else inode->i_op = &v9fs_dir_inode_operations; @@ -575,7 +575,8 @@ v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode, flags = O_RDWR; fid = v9fs_create(v9ses, dir, dentry, NULL, perm, - v9fs_uflags2omode(flags, v9fs_extended(v9ses))); + v9fs_uflags2omode(flags, + v9fs_proto_dotu(v9ses))); if (IS_ERR(fid)) { err = PTR_ERR(fid); fid = NULL; @@ -858,7 +859,7 @@ static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr) if (iattr->ia_valid & ATTR_SIZE) wstat.length = iattr->ia_size; - if (v9fs_extended(v9ses)) { + if (v9fs_proto_dotu(v9ses)) { if (iattr->ia_valid & ATTR_UID) wstat.n_uid = iattr->ia_uid; @@ -886,6 +887,8 @@ v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode, struct super_block *sb) { char ext[32]; + char tag_name[14]; + unsigned int i_nlink; struct v9fs_session_info *v9ses = sb->s_fs_info; inode->i_nlink = 1; @@ -897,11 +900,26 @@ v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode, inode->i_uid = v9ses->dfltuid; inode->i_gid = v9ses->dfltgid; - if (v9fs_extended(v9ses)) { + if (v9fs_proto_dotu(v9ses)) { inode->i_uid = stat->n_uid; inode->i_gid = stat->n_gid; } - + if ((S_ISREG(inode->i_mode)) || (S_ISDIR(inode->i_mode))) { + if (v9fs_proto_dotu(v9ses) && (stat->extension[0] != '\0')) { + /* + * Hadlink support got added later to + * to the .u extension. So there can be + * server out there that doesn't support + * this even with .u extension. So check + * for non NULL stat->extension + */ + strncpy(ext, stat->extension, sizeof(ext)); + /* HARDLINKCOUNT %u */ + sscanf(ext, "%13s %u", tag_name, &i_nlink); + if (!strncmp(tag_name, "HARDLINKCOUNT", 13)) + inode->i_nlink = i_nlink; + } + } inode->i_mode = p9mode2unixmode(v9ses, stat->mode); if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode))) { char type = 0; @@ -976,7 +994,7 @@ static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen) if (IS_ERR(fid)) return PTR_ERR(fid); - if (!v9fs_extended(v9ses)) + if (!v9fs_proto_dotu(v9ses)) return -EBADF; st = p9_client_stat(fid); @@ -994,52 +1012,13 @@ static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen) P9_DPRINTK(P9_DEBUG_VFS, "%s -> %s (%s)\n", dentry->d_name.name, st->extension, buffer); - retval = buflen; - + retval = strnlen(buffer, buflen); done: kfree(st); return retval; } /** - * v9fs_vfs_readlink - read a symlink's location - * @dentry: dentry for symlink - * @buffer: buffer to load symlink location into - * @buflen: length of buffer - * - */ - -static int v9fs_vfs_readlink(struct dentry *dentry, char __user * buffer, - int buflen) -{ - int retval; - int ret; - char *link = __getname(); - - if (unlikely(!link)) - return -ENOMEM; - - if (buflen > PATH_MAX) - buflen = PATH_MAX; - - P9_DPRINTK(P9_DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_name.name, - dentry); - - retval = v9fs_readlink(dentry, link, buflen); - - if (retval > 0) { - if ((ret = copy_to_user(buffer, link, retval)) != 0) { - P9_DPRINTK(P9_DEBUG_ERROR, - "problem copying to user: %d\n", ret); - retval = ret; - } - } - - __putname(link); - return retval; -} - -/** * v9fs_vfs_follow_link - follow a symlink path * @dentry: dentry for symlink * @nd: nameidata @@ -1062,7 +1041,7 @@ static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd) __putname(link); link = ERR_PTR(len); } else - link[len] = 0; + link[min(len, PATH_MAX-1)] = 0; } nd_set_link(nd, link); @@ -1105,7 +1084,7 @@ static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry, struct p9_fid *fid; v9ses = v9fs_inode2v9ses(dir); - if (!v9fs_extended(v9ses)) { + if (!v9fs_proto_dotu(v9ses)) { P9_DPRINTK(P9_DEBUG_ERROR, "not extended\n"); return -EPERM; } @@ -1231,7 +1210,6 @@ static const struct inode_operations v9fs_dir_inode_operations_ext = { .rmdir = v9fs_vfs_rmdir, .mknod = v9fs_vfs_mknod, .rename = v9fs_vfs_rename, - .readlink = v9fs_vfs_readlink, .getattr = v9fs_vfs_getattr, .setattr = v9fs_vfs_setattr, }; @@ -1254,7 +1232,7 @@ static const struct inode_operations v9fs_file_inode_operations = { }; static const struct inode_operations v9fs_symlink_inode_operations = { - .readlink = v9fs_vfs_readlink, + .readlink = generic_readlink, .follow_link = v9fs_vfs_follow_link, .put_link = v9fs_vfs_put_link, .getattr = v9fs_vfs_getattr, diff --git a/fs/9p/vfs_super.c b/fs/9p/vfs_super.c index 14a86448572..69357c0d989 100644 --- a/fs/9p/vfs_super.c +++ b/fs/9p/vfs_super.c @@ -188,7 +188,8 @@ static void v9fs_kill_super(struct super_block *s) P9_DPRINTK(P9_DEBUG_VFS, " %p\n", s); - v9fs_dentry_release(s->s_root); /* clunk root */ + if (s->s_root) + v9fs_dentry_release(s->s_root); /* clunk root */ kill_anon_super(s); |