diff options
| -rw-r--r-- | fs/fuse/dir.c | 108 | ||||
| -rw-r--r-- | fs/fuse/fuse_i.h | 3 | ||||
| -rw-r--r-- | fs/fuse/inode.c | 4 | ||||
| -rw-r--r-- | include/uapi/linux/fuse.h | 3 |
4 files changed, 92 insertions, 26 deletions
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index 7b8f63e7489f..47395b0c3b35 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -1160,38 +1160,78 @@ static int fuse_permission(struct inode *inode, int mask) return err; } -static const char *fuse_get_link(struct dentry *dentry, - struct inode *inode, - struct delayed_call *done) +static int fuse_readlink_page(struct inode *inode, struct page *page) { struct fuse_conn *fc = get_fuse_conn(inode); - FUSE_ARGS(args); - char *link; - ssize_t ret; + struct fuse_req *req; + int err; - if (!dentry) - return ERR_PTR(-ECHILD); + req = fuse_get_req(fc, 1); + if (IS_ERR(req)) + return PTR_ERR(req); + + req->out.page_zeroing = 1; + req->out.argpages = 1; + req->num_pages = 1; + req->pages[0] = page; + req->page_descs[0].length = PAGE_SIZE - 1; + req->in.h.opcode = FUSE_READLINK; + req->in.h.nodeid = get_node_id(inode); + req->out.argvar = 1; + req->out.numargs = 1; + req->out.args[0].size = PAGE_SIZE - 1; + fuse_request_send(fc, req); + err = req->out.h.error; - link = kmalloc(PAGE_SIZE, GFP_KERNEL); - if (!link) - return ERR_PTR(-ENOMEM); + if (!err) { + char *link = page_address(page); + size_t len = req->out.args[0].size; - args.in.h.opcode = FUSE_READLINK; - args.in.h.nodeid = get_node_id(inode); - args.out.argvar = 1; - args.out.numargs = 1; - args.out.args[0].size = PAGE_SIZE - 1; - args.out.args[0].value = link; - ret = fuse_simple_request(fc, &args); - if (ret < 0) { - kfree(link); - link = ERR_PTR(ret); - } else { - link[ret] = '\0'; - set_delayed_call(done, kfree_link, link); + BUG_ON(len >= PAGE_SIZE); + link[len] = '\0'; } + + fuse_put_request(fc, req); fuse_invalidate_atime(inode); - return link; + + return err; +} + +static const char *fuse_get_link(struct dentry *dentry, struct inode *inode, + struct delayed_call *callback) +{ + struct fuse_conn *fc = get_fuse_conn(inode); + struct page *page; + int err; + + err = -EIO; + if (is_bad_inode(inode)) + goto out_err; + + if (fc->cache_symlinks) + return page_get_link(dentry, inode, callback); + + err = -ECHILD; + if (!dentry) + goto out_err; + + page = alloc_page(GFP_KERNEL); + err = -ENOMEM; + if (!page) + goto out_err; + + err = fuse_readlink_page(inode, page); + if (err) { + __free_page(page); + goto out_err; + } + + set_delayed_call(callback, page_put_link, page); + + return page_address(page); + +out_err: + return ERR_PTR(err); } static int fuse_dir_open(struct inode *inode, struct file *file) @@ -1644,7 +1684,25 @@ void fuse_init_dir(struct inode *inode) fi->rdc.version = 0; } +static int fuse_symlink_readpage(struct file *null, struct page *page) +{ + int err = fuse_readlink_page(page->mapping->host, page); + + if (!err) + SetPageUptodate(page); + + unlock_page(page); + + return err; +} + +static const struct address_space_operations fuse_symlink_aops = { + .readpage = fuse_symlink_readpage, +}; + void fuse_init_symlink(struct inode *inode) { inode->i_op = &fuse_symlink_inode_operations; + inode->i_data.a_ops = &fuse_symlink_aops; + inode_nohighmem(inode); } diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index 0e32524e66bb..e9f712e81c7d 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -613,6 +613,9 @@ struct fuse_conn { /** handle fs handles killing suid/sgid/cap on write/chown/trunc */ unsigned handle_killpriv:1; + /** cache READLINK responses in page cache */ + unsigned cache_symlinks:1; + /* * The following bitfields are only for optimization purposes * and hence races in setting them will not cause malfunction diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index d5f845aefbc9..0b94b23b02d4 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -928,6 +928,8 @@ static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req) fc->posix_acl = 1; fc->sb->s_xattr = fuse_acl_xattr_handlers; } + if (arg->flags & FUSE_CACHE_SYMLINKS) + fc->cache_symlinks = 1; if (arg->flags & FUSE_ABORT_ERROR) fc->abort_err = 1; if (arg->flags & FUSE_MAX_PAGES) { @@ -966,7 +968,7 @@ static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req) FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO | FUSE_WRITEBACK_CACHE | FUSE_NO_OPEN_SUPPORT | FUSE_PARALLEL_DIROPS | FUSE_HANDLE_KILLPRIV | FUSE_POSIX_ACL | - FUSE_ABORT_ERROR | FUSE_MAX_PAGES; + FUSE_ABORT_ERROR | FUSE_MAX_PAGES | FUSE_CACHE_SYMLINKS; req->in.h.opcode = FUSE_INIT; req->in.numargs = 1; req->in.args[0].size = sizeof(*arg); diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h index 76f46f159992..b4967d48bfda 100644 --- a/include/uapi/linux/fuse.h +++ b/include/uapi/linux/fuse.h @@ -121,6 +121,7 @@ * - add FUSE_COPY_FILE_RANGE * - add FOPEN_CACHE_DIR * - add FUSE_MAX_PAGES, add max_pages to init_out + * - add FUSE_CACHE_SYMLINKS */ #ifndef _LINUX_FUSE_H @@ -257,6 +258,7 @@ struct fuse_file_lock { * FUSE_POSIX_ACL: filesystem supports posix acls * FUSE_ABORT_ERROR: reading the device after abort returns ECONNABORTED * FUSE_MAX_PAGES: init_out.max_pages contains the max number of req pages + * FUSE_CACHE_SYMLINKS: cache READLINK responses */ #define FUSE_ASYNC_READ (1 << 0) #define FUSE_POSIX_LOCKS (1 << 1) @@ -281,6 +283,7 @@ struct fuse_file_lock { #define FUSE_POSIX_ACL (1 << 20) #define FUSE_ABORT_ERROR (1 << 21) #define FUSE_MAX_PAGES (1 << 22) +#define FUSE_CACHE_SYMLINKS (1 << 23) /** * CUSE INIT request/reply flags |