From c8ccbe032feb127a977c66865cb63d72d9a6e08b Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Tue, 5 Jun 2012 15:10:22 +0200 Subject: [PATCH] fuse: 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 Signed-off-by: Al Viro --- fs/fuse/dir.c | 94 ++++++++++++++++++++++++++++++++++++++++++----------------- 1 file changed, 67 insertions(+), 27 deletions(-) diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index f7543f7..e42442f 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -369,8 +369,9 @@ static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry, * If the filesystem doesn't support this, then fall back to separate * 'mknod' + 'open' requests. */ -static int fuse_create_open(struct inode *dir, struct dentry *entry, - umode_t mode, struct nameidata *nd) +static struct file *fuse_create_open(struct inode *dir, struct dentry *entry, + struct opendata *od, unsigned flags, + umode_t mode) { int err; struct inode *inode; @@ -382,14 +383,11 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry, struct fuse_entry_out outentry; struct fuse_file *ff; struct file *file; - int flags = nd->intent.open.flags; - - if (fc->no_create) - return -ENOSYS; forget = fuse_alloc_forget(); + err = -ENOMEM; if (!forget) - return -ENOMEM; + goto out_err; req = fuse_get_req(fc); err = PTR_ERR(req); @@ -428,11 +426,8 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry, req->out.args[1].value = &outopen; fuse_request_send(fc, req); err = req->out.h.error; - if (err) { - if (err == -ENOSYS) - fc->no_create = 1; + if (err) goto out_free_ff; - } err = -EIO; if (!S_ISREG(outentry.attr.mode) || invalid_nodeid(outentry.nodeid)) @@ -448,28 +443,78 @@ static int fuse_create_open(struct inode *dir, struct dentry *entry, flags &= ~(O_CREAT | O_EXCL | O_TRUNC); fuse_sync_release(ff, flags); fuse_queue_forget(fc, forget, outentry.nodeid, 1); - return -ENOMEM; + err = -ENOMEM; + goto out_err; } kfree(forget); d_instantiate(entry, inode); fuse_change_entry_timeout(entry, &outentry); fuse_invalidate_attr(dir); - file = lookup_instantiate_filp(nd, entry, generic_file_open); + file = finish_open(od, entry, generic_file_open); if (IS_ERR(file)) { fuse_sync_release(ff, flags); - return PTR_ERR(file); + } else { + file->private_data = fuse_file_get(ff); + fuse_finish_open(inode, file); } - file->private_data = fuse_file_get(ff); - fuse_finish_open(inode, file); - return 0; + return file; - out_free_ff: +out_free_ff: fuse_file_free(ff); - out_put_request: +out_put_request: fuse_put_request(fc, req); - out_put_forget_req: +out_put_forget_req: kfree(forget); - return err; +out_err: + return ERR_PTR(err); +} + +static int fuse_mknod(struct inode *, struct dentry *, umode_t, dev_t); +static struct file *fuse_atomic_open(struct inode *dir, struct dentry *entry, + struct opendata *od, unsigned flags, + umode_t mode, bool *created) +{ + int err; + struct fuse_conn *fc = get_fuse_conn(dir); + struct file *file; + struct dentry *res = NULL; + + if (d_unhashed(entry)) { + res = fuse_lookup(dir, entry, NULL); + if (IS_ERR(res)) + return ERR_CAST(res); + + if (res) + entry = res; + } + + if (!(flags & O_CREAT) || entry->d_inode) + goto no_open; + + /* Only creates */ + *created = true; + + if (fc->no_create) + goto mknod; + + file = fuse_create_open(dir, entry, od, flags, mode); + if (PTR_ERR(file) == -ENOSYS) { + fc->no_create = 1; + goto mknod; + } +out_dput: + dput(res); + return file; + +mknod: + err = fuse_mknod(dir, entry, mode, 0); + if (err) { + file = ERR_PTR(err); + goto out_dput; + } +no_open: + finish_no_open(od, res); + return NULL; } /* @@ -573,12 +618,6 @@ static int fuse_mknod(struct inode *dir, struct dentry *entry, umode_t mode, static int fuse_create(struct inode *dir, struct dentry *entry, umode_t mode, struct nameidata *nd) { - if (nd) { - int err = fuse_create_open(dir, entry, mode, nd); - if (err != -ENOSYS) - return err; - /* Fall back on mknod */ - } return fuse_mknod(dir, entry, mode, 0); } @@ -1646,6 +1685,7 @@ static const struct inode_operations fuse_dir_inode_operations = { .link = fuse_link, .setattr = fuse_setattr, .create = fuse_create, + .atomic_open = fuse_atomic_open, .mknod = fuse_mknod, .permission = fuse_permission, .getattr = fuse_getattr, -- 2.7.4