From e43ae79c540270865918dab5ac914c74f43101e2 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Tue, 5 Jun 2012 15:10:26 +0200 Subject: [PATCH] 9p: implement i_op->atomic_open() Add an ->atomic_open implementation which replaces the atomic open+create operation implemented via ->create. No functionality is changed. Signed-off-by: Miklos Szeredi CC: Eric Van Hensbergen Signed-off-by: Al Viro --- fs/9p/vfs_inode.c | 169 +++++++++++++++++++++++++---------------- fs/9p/vfs_inode_dotl.c | 52 ++++++++----- 2 files changed, 137 insertions(+), 84 deletions(-) diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c index 57ccb7537dae..e8c42ceb89ba 100644 --- a/fs/9p/vfs_inode.c +++ b/fs/9p/vfs_inode.c @@ -712,11 +712,14 @@ error: } /** - * v9fs_vfs_create - VFS hook to create files + * v9fs_vfs_create - VFS hook to create a regular file + * + * open(.., O_CREAT) is handled in v9fs_vfs_atomic_open(). This is only called + * for mknod(2). + * * @dir: directory inode that is being created * @dentry: dentry that is being deleted * @mode: create permissions - * @nd: path information * */ @@ -724,76 +727,19 @@ static int v9fs_vfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, struct nameidata *nd) { - int err; - u32 perm; - int flags; - struct file *filp; - struct v9fs_inode *v9inode; - struct v9fs_session_info *v9ses; - struct p9_fid *fid, *inode_fid; - - err = 0; - fid = NULL; - v9ses = v9fs_inode2v9ses(dir); - perm = unixmode2p9mode(v9ses, mode); - if (nd) - flags = nd->intent.open.flags; - else - flags = O_RDWR; + struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir); + u32 perm = unixmode2p9mode(v9ses, mode); + struct p9_fid *fid; - fid = v9fs_create(v9ses, dir, dentry, NULL, perm, - v9fs_uflags2omode(flags, - v9fs_proto_dotu(v9ses))); - if (IS_ERR(fid)) { - err = PTR_ERR(fid); - fid = NULL; - goto error; - } + /* P9_OEXCL? */ + fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_ORDWR); + if (IS_ERR(fid)) + return PTR_ERR(fid); v9fs_invalidate_inode_attr(dir); - /* if we are opening a file, assign the open fid to the file */ - if (nd) { - v9inode = V9FS_I(dentry->d_inode); - mutex_lock(&v9inode->v_mutex); - if (v9ses->cache && !v9inode->writeback_fid && - ((flags & O_ACCMODE) != O_RDONLY)) { - /* - * clone a fid and add it to writeback_fid - * we do it during open time instead of - * page dirty time via write_begin/page_mkwrite - * because we want write after unlink usecase - * to work. - */ - inode_fid = v9fs_writeback_fid(dentry); - if (IS_ERR(inode_fid)) { - err = PTR_ERR(inode_fid); - mutex_unlock(&v9inode->v_mutex); - goto error; - } - v9inode->writeback_fid = (void *) inode_fid; - } - mutex_unlock(&v9inode->v_mutex); - filp = lookup_instantiate_filp(nd, dentry, generic_file_open); - if (IS_ERR(filp)) { - err = PTR_ERR(filp); - goto error; - } - - filp->private_data = fid; -#ifdef CONFIG_9P_FSCACHE - if (v9ses->cache) - v9fs_cache_inode_set_cookie(dentry->d_inode, filp); -#endif - } else - p9_client_clunk(fid); + p9_client_clunk(fid); return 0; - -error: - if (fid) - p9_client_clunk(fid); - - return err; } /** @@ -910,6 +856,93 @@ error: return ERR_PTR(result); } +static struct file * +v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry, + struct opendata *od, unsigned flags, umode_t mode, + bool *created) +{ + int err; + u32 perm; + struct file *filp; + struct v9fs_inode *v9inode; + struct v9fs_session_info *v9ses; + struct p9_fid *fid, *inode_fid; + struct dentry *res = NULL; + + if (d_unhashed(dentry)) { + res = v9fs_vfs_lookup(dir, dentry, NULL); + if (IS_ERR(res)) + return ERR_CAST(res); + + if (res) + dentry = res; + } + + /* Only creates */ + if (!(flags & O_CREAT) || dentry->d_inode) { + finish_no_open(od, res); + return NULL; + } + + err = 0; + fid = NULL; + v9ses = v9fs_inode2v9ses(dir); + perm = unixmode2p9mode(v9ses, mode); + fid = v9fs_create(v9ses, dir, dentry, NULL, perm, + v9fs_uflags2omode(flags, + v9fs_proto_dotu(v9ses))); + if (IS_ERR(fid)) { + err = PTR_ERR(fid); + fid = NULL; + goto error; + } + + v9fs_invalidate_inode_attr(dir); + v9inode = V9FS_I(dentry->d_inode); + mutex_lock(&v9inode->v_mutex); + if (v9ses->cache && !v9inode->writeback_fid && + ((flags & O_ACCMODE) != O_RDONLY)) { + /* + * clone a fid and add it to writeback_fid + * we do it during open time instead of + * page dirty time via write_begin/page_mkwrite + * because we want write after unlink usecase + * to work. + */ + inode_fid = v9fs_writeback_fid(dentry); + if (IS_ERR(inode_fid)) { + err = PTR_ERR(inode_fid); + mutex_unlock(&v9inode->v_mutex); + goto error; + } + v9inode->writeback_fid = (void *) inode_fid; + } + mutex_unlock(&v9inode->v_mutex); + filp = finish_open(od, dentry, generic_file_open); + if (IS_ERR(filp)) { + err = PTR_ERR(filp); + goto error; + } + + filp->private_data = fid; +#ifdef CONFIG_9P_FSCACHE + if (v9ses->cache) + v9fs_cache_inode_set_cookie(dentry->d_inode, filp); +#endif + + *created = true; +out: + dput(res); + return filp; + +error: + if (fid) + p9_client_clunk(fid); + + filp = ERR_PTR(err); + goto out; +} + /** * v9fs_vfs_unlink - VFS unlink hook to delete an inode * @i: inode that is being unlinked @@ -1488,6 +1521,7 @@ out: static const struct inode_operations v9fs_dir_inode_operations_dotu = { .create = v9fs_vfs_create, .lookup = v9fs_vfs_lookup, + .atomic_open = v9fs_vfs_atomic_open, .symlink = v9fs_vfs_symlink, .link = v9fs_vfs_link, .unlink = v9fs_vfs_unlink, @@ -1502,6 +1536,7 @@ static const struct inode_operations v9fs_dir_inode_operations_dotu = { static const struct inode_operations v9fs_dir_inode_operations = { .create = v9fs_vfs_create, .lookup = v9fs_vfs_lookup, + .atomic_open = v9fs_vfs_atomic_open, .unlink = v9fs_vfs_unlink, .mkdir = v9fs_vfs_mkdir, .rmdir = v9fs_vfs_rmdir, diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c index e3dd2a1e2bfc..a354fe2cb234 100644 --- a/fs/9p/vfs_inode_dotl.c +++ b/fs/9p/vfs_inode_dotl.c @@ -230,17 +230,23 @@ int v9fs_open_to_dotl_flags(int flags) * @dir: directory inode that is being created * @dentry: dentry that is being deleted * @mode: create permissions - * @nd: path information * */ static int v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode, struct nameidata *nd) +{ + return v9fs_vfs_mknod_dotl(dir, dentry, omode, 0); +} + +static struct file * +v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry, + struct opendata *od, unsigned flags, umode_t omode, + bool *created) { int err = 0; gid_t gid; - int flags; umode_t mode; char *name = NULL; struct file *filp; @@ -251,19 +257,25 @@ v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode, struct p9_fid *dfid, *ofid, *inode_fid; struct v9fs_session_info *v9ses; struct posix_acl *pacl = NULL, *dacl = NULL; + struct dentry *res = NULL; - v9ses = v9fs_inode2v9ses(dir); - if (nd) - flags = nd->intent.open.flags; - else { - /* - * create call without LOOKUP_OPEN is due - * to mknod of regular files. So use mknod - * operation. - */ - return v9fs_vfs_mknod_dotl(dir, dentry, omode, 0); + if (d_unhashed(dentry)) { + res = v9fs_vfs_lookup(dir, dentry, NULL); + if (IS_ERR(res)) + return ERR_CAST(res); + + if (res) + dentry = res; + } + + /* Only creates */ + if (!(flags & O_CREAT) || dentry->d_inode) { + finish_no_open(od, res); + return NULL; } + v9ses = v9fs_inode2v9ses(dir); + name = (char *) dentry->d_name.name; p9_debug(P9_DEBUG_VFS, "name:%s flags:0x%x mode:0x%hx\n", name, flags, omode); @@ -272,7 +284,7 @@ v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode, if (IS_ERR(dfid)) { err = PTR_ERR(dfid); p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err); - return err; + goto err_return; } /* clone a fid to use for creation */ @@ -280,7 +292,7 @@ v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode, if (IS_ERR(ofid)) { err = PTR_ERR(ofid); p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err); - return err; + goto err_return; } gid = v9fs_get_fsgid_for_create(dir); @@ -345,7 +357,7 @@ v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode, } mutex_unlock(&v9inode->v_mutex); /* Since we are opening a file, assign the open fid to the file */ - filp = lookup_instantiate_filp(nd, dentry, generic_file_open); + filp = finish_open(od, dentry, generic_file_open); if (IS_ERR(filp)) { err = PTR_ERR(filp); goto err_clunk_old_fid; @@ -355,7 +367,10 @@ v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode, if (v9ses->cache) v9fs_cache_inode_set_cookie(inode, filp); #endif - return 0; + *created = true; +out: + dput(res); + return filp; error: if (fid) @@ -364,7 +379,9 @@ err_clunk_old_fid: if (ofid) p9_client_clunk(ofid); v9fs_set_create_acl(NULL, &dacl, &pacl); - return err; +err_return: + filp = ERR_PTR(err); + goto out; } /** @@ -982,6 +999,7 @@ out: const struct inode_operations v9fs_dir_inode_operations_dotl = { .create = v9fs_vfs_create_dotl, + .atomic_open = v9fs_vfs_atomic_open_dotl, .lookup = v9fs_vfs_lookup, .link = v9fs_vfs_link_dotl, .symlink = v9fs_vfs_symlink_dotl, -- 2.30.2