diff mbox series

[v4,9/9] ceph: attempt to do async create when possible

Message ID 20200212172729.260752-10-jlayton@kernel.org (mailing list archive)
State New, archived
Headers show
Series ceph: add support for asynchronous directory operations | expand

Commit Message

Jeffrey Layton Feb. 12, 2020, 5:27 p.m. UTC
With the Octopus release, the MDS will hand out directory create caps.

If we have Fxc caps on the directory, and complete directory information
or a known negative dentry, then we can return without waiting on the
reply, allowing the open() call to return very quickly to userland.

We use the normal ceph_fill_inode() routine to fill in the inode, so we
have to gin up some reply inode information with what we'd expect the
newly-created inode to have. The client assumes that it has a full set
of caps on the new inode, and that the MDS will revoke them when there
is conflicting access.

This functionality is gated on the wsync/nowsync mount options.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
 fs/ceph/file.c               | 231 +++++++++++++++++++++++++++++++++--
 include/linux/ceph/ceph_fs.h |   3 +
 2 files changed, 224 insertions(+), 10 deletions(-)

Comments

Yan, Zheng Feb. 13, 2020, 12:44 p.m. UTC | #1
On Thu, Feb 13, 2020 at 1:30 AM Jeff Layton <jlayton@kernel.org> wrote:
>
> With the Octopus release, the MDS will hand out directory create caps.
>
> If we have Fxc caps on the directory, and complete directory information
> or a known negative dentry, then we can return without waiting on the
> reply, allowing the open() call to return very quickly to userland.
>
> We use the normal ceph_fill_inode() routine to fill in the inode, so we
> have to gin up some reply inode information with what we'd expect the
> newly-created inode to have. The client assumes that it has a full set
> of caps on the new inode, and that the MDS will revoke them when there
> is conflicting access.
>
> This functionality is gated on the wsync/nowsync mount options.
>
> Signed-off-by: Jeff Layton <jlayton@kernel.org>
> ---
>  fs/ceph/file.c               | 231 +++++++++++++++++++++++++++++++++--
>  include/linux/ceph/ceph_fs.h |   3 +
>  2 files changed, 224 insertions(+), 10 deletions(-)
>
> diff --git a/fs/ceph/file.c b/fs/ceph/file.c
> index 472d90ccdf44..814ff435832c 100644
> --- a/fs/ceph/file.c
> +++ b/fs/ceph/file.c
> @@ -448,6 +448,196 @@ cache_file_layout(struct inode *dst, struct inode *src)
>         spin_unlock(&cdst->i_ceph_lock);
>  }
>
> +/*
> + * Try to set up an async create. We need caps, a file layout, and inode number,
> + * and either a lease on the dentry or complete dir info. If any of those
> + * criteria are not satisfied, then return false and the caller can go
> + * synchronous.
> + */
> +static bool try_prep_async_create(struct inode *dir, struct dentry *dentry,
> +                                 struct ceph_file_layout *lo, u64 *pino)
> +{
> +       struct ceph_inode_info *ci = ceph_inode(dir);
> +       struct ceph_dentry_info *di = ceph_dentry(dentry);
> +       bool ret = false;
> +       u64 ino;
> +
> +       spin_lock(&ci->i_ceph_lock);
> +       /* No auth cap means no chance for Dc caps */
> +       if (!ci->i_auth_cap)
> +               goto no_async;
> +
> +       /* Any delegated inos? */
> +       if (xa_empty(&ci->i_auth_cap->session->s_delegated_inos))
> +               goto no_async;
> +
> +       if (!ceph_file_layout_is_valid(&ci->i_cached_layout))
> +               goto no_async;
> +
> +       if ((__ceph_caps_issued(ci, NULL) &
> +            (CEPH_CAP_FILE_EXCL | CEPH_CAP_DIR_CREATE)) !=
> +           (CEPH_CAP_FILE_EXCL | CEPH_CAP_DIR_CREATE))
> +               goto no_async;
> +
> +       if (d_in_lookup(dentry)) {
> +               if (!__ceph_dir_is_complete(ci))
> +                       goto no_async;
> +       } else if (atomic_read(&ci->i_shared_gen) !=
> +                  READ_ONCE(di->lease_shared_gen)) {
> +               goto no_async;
> +       }
> +
> +       ino = ceph_get_deleg_ino(ci->i_auth_cap->session);
> +       if (!ino)
> +               goto no_async;
> +
> +       *pino = ino;
> +       ceph_take_cap_refs(ci, CEPH_CAP_FILE_EXCL | CEPH_CAP_DIR_CREATE, false);
> +       memcpy(lo, &ci->i_cached_layout, sizeof(*lo));
> +       rcu_assign_pointer(lo->pool_ns,
> +                          ceph_try_get_string(ci->i_cached_layout.pool_ns));
> +       ret = true;
> +no_async:
> +       spin_unlock(&ci->i_ceph_lock);
> +       return ret;
> +}
> +
> +static void ceph_async_create_cb(struct ceph_mds_client *mdsc,
> +                                 struct ceph_mds_request *req)
> +{
> +       int result = req->r_err ? req->r_err :
> +                       le32_to_cpu(req->r_reply_info.head->result);
> +
> +       mapping_set_error(req->r_parent->i_mapping, result);
> +
> +       if (result) {
> +               struct dentry *dentry = req->r_dentry;
> +               int pathlen;
> +               u64 base;
> +               char *path = ceph_mdsc_build_path(req->r_dentry, &pathlen,
> +                                                 &base, 0);
> +
> +               ceph_dir_clear_complete(req->r_parent);
> +               if (!d_unhashed(dentry))
> +                       d_drop(dentry);
> +
> +               /* FIXME: start returning I/O errors on all accesses? */
> +               pr_warn("ceph: async create failure path=(%llx)%s result=%d!\n",
> +                       base, IS_ERR(path) ? "<<bad>>" : path, result);
> +               ceph_mdsc_free_path(path, pathlen);
> +       }
> +
> +       if (req->r_target_inode) {
> +               struct ceph_inode_info *ci = ceph_inode(req->r_target_inode);
> +               u64 ino = ceph_vino(req->r_target_inode).ino;
> +
> +               if (req->r_deleg_ino != ino)
> +                       pr_warn("%s: inode number mismatch! err=%d deleg_ino=0x%llx target=0x%llx\n",
> +                               __func__, req->r_err, req->r_deleg_ino, ino);
> +               mapping_set_error(req->r_target_inode->i_mapping, result);
> +
> +               spin_lock(&ci->i_ceph_lock);
> +               if (ci->i_ceph_flags & CEPH_I_ASYNC_CREATE) {
> +                       ci->i_ceph_flags &= ~CEPH_I_ASYNC_CREATE;
> +                       wake_up_bit(&ci->i_ceph_flags, CEPH_ASYNC_CREATE_BIT);
> +               }
> +               spin_unlock(&ci->i_ceph_lock);
> +       } else {
> +               pr_warn("%s: no req->r_target_inode for 0x%llx\n", __func__,
> +                       req->r_deleg_ino);
> +       }
> +       ceph_put_cap_refs(ceph_inode(req->r_parent),
> +                         CEPH_CAP_FILE_EXCL | CEPH_CAP_DIR_CREATE);
> +}
> +
> +static int ceph_finish_async_create(struct inode *dir, struct dentry *dentry,
> +                                   struct file *file, umode_t mode,
> +                                   struct ceph_mds_request *req,
> +                                   struct ceph_acl_sec_ctx *as_ctx,
> +                                   struct ceph_file_layout *lo)
> +{
> +       int ret;
> +       char xattr_buf[4];
> +       struct ceph_mds_reply_inode in = { };
> +       struct ceph_mds_reply_info_in iinfo = { .in = &in };
> +       struct ceph_inode_info *ci = ceph_inode(dir);
> +       struct inode *inode;
> +       struct timespec64 now;
> +       struct ceph_vino vino = { .ino = req->r_deleg_ino,
> +                                 .snap = CEPH_NOSNAP };
> +
> +       ktime_get_real_ts64(&now);
> +
> +       inode = ceph_get_inode(dentry->d_sb, vino);
> +       if (IS_ERR(inode))
> +               return PTR_ERR(inode);
> +
> +       iinfo.inline_version = CEPH_INLINE_NONE;
> +       iinfo.change_attr = 1;
> +       ceph_encode_timespec64(&iinfo.btime, &now);
> +
> +       iinfo.xattr_len = ARRAY_SIZE(xattr_buf);
> +       iinfo.xattr_data = xattr_buf;
> +       memset(iinfo.xattr_data, 0, iinfo.xattr_len);
> +
> +       in.ino = cpu_to_le64(vino.ino);
> +       in.snapid = cpu_to_le64(CEPH_NOSNAP);
> +       in.version = cpu_to_le64(1);    // ???
> +       in.cap.caps = in.cap.wanted = cpu_to_le32(CEPH_CAP_ALL_FILE);
> +       in.cap.cap_id = cpu_to_le64(1);
> +       in.cap.realm = cpu_to_le64(ci->i_snap_realm->ino);
> +       in.cap.flags = CEPH_CAP_FLAG_AUTH;
> +       in.ctime = in.mtime = in.atime = iinfo.btime;
> +       in.mode = cpu_to_le32((u32)mode);
> +       in.truncate_seq = cpu_to_le32(1);
> +       in.truncate_size = cpu_to_le64(-1ULL);
> +       in.xattr_version = cpu_to_le64(1);
> +       in.uid = cpu_to_le32(from_kuid(&init_user_ns, current_fsuid()));
> +       in.gid = cpu_to_le32(from_kgid(&init_user_ns, dir->i_mode & S_ISGID ?
> +                               dir->i_gid : current_fsgid()));
> +       in.nlink = cpu_to_le32(1);
> +       in.max_size = cpu_to_le64(lo->stripe_unit);
> +
> +       ceph_file_layout_to_legacy(lo, &in.layout);
> +
> +       ret = ceph_fill_inode(inode, NULL, &iinfo, NULL, req->r_session,
> +                             req->r_fmode, NULL);
> +       if (ret) {
> +               dout("%s failed to fill inode: %d\n", __func__, ret);
> +               ceph_dir_clear_complete(dir);
> +               if (!d_unhashed(dentry))
> +                       d_drop(dentry);
> +               if (inode->i_state & I_NEW)
> +                       discard_new_inode(inode);
> +       } else {
> +               struct dentry *dn;
> +
> +               dout("%s d_adding new inode 0x%llx to 0x%lx/%s\n", __func__,
> +                       vino.ino, dir->i_ino, dentry->d_name.name);
> +               ceph_dir_clear_ordered(dir);
> +               ceph_init_inode_acls(inode, as_ctx);
> +               if (inode->i_state & I_NEW) {
> +                       /*
> +                        * If it's not I_NEW, then someone created this before
> +                        * we got here. Assume the server is aware of it at
> +                        * that point and don't worry about setting
> +                        * CEPH_I_ASYNC_CREATE.
> +                        */
> +                       ceph_inode(inode)->i_ceph_flags = CEPH_I_ASYNC_CREATE;
> +                       unlock_new_inode(inode);
> +               }
> +               if (d_in_lookup(dentry) || d_really_is_negative(dentry)) {
> +                       if (!d_unhashed(dentry))
> +                               d_drop(dentry);
> +                       dn = d_splice_alias(inode, dentry);
> +                       WARN_ON_ONCE(dn && dn != dentry);
> +               }
> +               file->f_mode |= FMODE_CREATED;
> +               ret = finish_open(file, dentry, ceph_open);
> +       }
> +       return ret;
> +}
> +
>  /*
>   * Do a lookup + open with a single request.  If we get a non-existent
>   * file or symlink, return 1 so the VFS can retry.
> @@ -460,6 +650,7 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
>         struct ceph_mds_request *req;
>         struct dentry *dn;
>         struct ceph_acl_sec_ctx as_ctx = {};
> +       bool try_async = ceph_test_mount_opt(fsc, ASYNC_DIROPS);
>         int mask;
>         int err;
>
> @@ -483,7 +674,7 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
>                 /* If it's not being looked up, it's negative */
>                 return -ENOENT;
>         }
> -
> +retry:
>         /* do the open */
>         req = prepare_open_request(dir->i_sb, flags, mode);
>         if (IS_ERR(req)) {
> @@ -492,28 +683,47 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
>         }
>         req->r_dentry = dget(dentry);
>         req->r_num_caps = 2;
> +       mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
> +       if (ceph_security_xattr_wanted(dir))
> +               mask |= CEPH_CAP_XATTR_SHARED;
> +       req->r_args.open.mask = cpu_to_le32(mask);
> +       req->r_parent = dir;
> +
>         if (flags & O_CREAT) {
> +               struct ceph_file_layout lo;
> +
>                 req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
>                 req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
>                 if (as_ctx.pagelist) {
>                         req->r_pagelist = as_ctx.pagelist;
>                         as_ctx.pagelist = NULL;
>                 }
> +               if (try_async && try_prep_async_create(dir, dentry, &lo,
> +                                                      &req->r_deleg_ino)) {
> +                       set_bit(CEPH_MDS_R_ASYNC, &req->r_req_flags);
> +                       req->r_args.open.flags |= cpu_to_le32(CEPH_O_EXCL);
> +                       req->r_callback = ceph_async_create_cb;
> +                       err = ceph_mdsc_submit_request(mdsc, dir, req);
> +                       if (!err) {
> +                               err = ceph_finish_async_create(dir, dentry,
> +                                                       file, mode, req,
> +                                                       &as_ctx, &lo);
> +                       } else if (err == -EJUKEBOX) {
> +                               ceph_mdsc_put_request(req);
> +                               try_async = false;
> +                               goto retry;

put ino number back to s_delegated_inos

> +                       }
> +                       goto out_req;
> +               }
>         }
>
> -       mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
> -       if (ceph_security_xattr_wanted(dir))
> -               mask |= CEPH_CAP_XATTR_SHARED;
> -       req->r_args.open.mask = cpu_to_le32(mask);
> -
> -       req->r_parent = dir;
>         set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
>         err = ceph_mdsc_do_request(mdsc,
>                                    (flags & (O_CREAT|O_TRUNC)) ? dir : NULL,
>                                    req);
>         err = ceph_handle_snapdir(req, dentry, err);
>         if (err)
> -               goto out_req;
> +               goto out_fmode;
>
>         if ((flags & O_CREAT) && !req->r_reply_info.head->is_dentry)
>                 err = ceph_handle_notrace_create(dir, dentry);
> @@ -527,7 +737,7 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
>                 dn = NULL;
>         }
>         if (err)
> -               goto out_req;
> +               goto out_fmode;
>         if (dn || d_really_is_negative(dentry) || d_is_symlink(dentry)) {
>                 /* make vfs retry on splice, ENOENT, or symlink */
>                 dout("atomic_open finish_no_open on dn %p\n", dn);
> @@ -543,9 +753,10 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
>                 }
>                 err = finish_open(file, dentry, ceph_open);
>         }
> -out_req:
> +out_fmode:
>         if (!req->r_err && req->r_target_inode)
>                 ceph_put_fmode(ceph_inode(req->r_target_inode), req->r_fmode);
> +out_req:
>         ceph_mdsc_put_request(req);
>  out_ctx:
>         ceph_release_acl_sec_ctx(&as_ctx);
> diff --git a/include/linux/ceph/ceph_fs.h b/include/linux/ceph/ceph_fs.h
> index 91d09cf37649..e035c5194005 100644
> --- a/include/linux/ceph/ceph_fs.h
> +++ b/include/linux/ceph/ceph_fs.h
> @@ -659,6 +659,9 @@ int ceph_flags_to_mode(int flags);
>  #define CEPH_CAP_ANY      (CEPH_CAP_ANY_RD | CEPH_CAP_ANY_EXCL | \
>                            CEPH_CAP_ANY_FILE_WR | CEPH_CAP_FILE_LAZYIO | \
>                            CEPH_CAP_PIN)
> +#define CEPH_CAP_ALL_FILE (CEPH_CAP_PIN | CEPH_CAP_ANY_SHARED | \
> +                          CEPH_CAP_AUTH_EXCL | CEPH_CAP_XATTR_EXCL | \
> +                          CEPH_CAP_ANY_FILE_RD | CEPH_CAP_ANY_FILE_WR)
>
>  #define CEPH_CAP_LOCKS (CEPH_LOCK_IFILE | CEPH_LOCK_IAUTH | CEPH_LOCK_ILINK | \
>                         CEPH_LOCK_IXATTR)
> --
> 2.24.1
>
diff mbox series

Patch

diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 472d90ccdf44..814ff435832c 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -448,6 +448,196 @@  cache_file_layout(struct inode *dst, struct inode *src)
 	spin_unlock(&cdst->i_ceph_lock);
 }
 
+/*
+ * Try to set up an async create. We need caps, a file layout, and inode number,
+ * and either a lease on the dentry or complete dir info. If any of those
+ * criteria are not satisfied, then return false and the caller can go
+ * synchronous.
+ */
+static bool try_prep_async_create(struct inode *dir, struct dentry *dentry,
+				  struct ceph_file_layout *lo, u64 *pino)
+{
+	struct ceph_inode_info *ci = ceph_inode(dir);
+	struct ceph_dentry_info *di = ceph_dentry(dentry);
+	bool ret = false;
+	u64 ino;
+
+	spin_lock(&ci->i_ceph_lock);
+	/* No auth cap means no chance for Dc caps */
+	if (!ci->i_auth_cap)
+		goto no_async;
+
+	/* Any delegated inos? */
+	if (xa_empty(&ci->i_auth_cap->session->s_delegated_inos))
+		goto no_async;
+
+	if (!ceph_file_layout_is_valid(&ci->i_cached_layout))
+		goto no_async;
+
+	if ((__ceph_caps_issued(ci, NULL) &
+	     (CEPH_CAP_FILE_EXCL | CEPH_CAP_DIR_CREATE)) !=
+	    (CEPH_CAP_FILE_EXCL | CEPH_CAP_DIR_CREATE))
+		goto no_async;
+
+	if (d_in_lookup(dentry)) {
+		if (!__ceph_dir_is_complete(ci))
+			goto no_async;
+	} else if (atomic_read(&ci->i_shared_gen) !=
+		   READ_ONCE(di->lease_shared_gen)) {
+		goto no_async;
+	}
+
+	ino = ceph_get_deleg_ino(ci->i_auth_cap->session);
+	if (!ino)
+		goto no_async;
+
+	*pino = ino;
+	ceph_take_cap_refs(ci, CEPH_CAP_FILE_EXCL | CEPH_CAP_DIR_CREATE, false);
+	memcpy(lo, &ci->i_cached_layout, sizeof(*lo));
+	rcu_assign_pointer(lo->pool_ns,
+			   ceph_try_get_string(ci->i_cached_layout.pool_ns));
+	ret = true;
+no_async:
+	spin_unlock(&ci->i_ceph_lock);
+	return ret;
+}
+
+static void ceph_async_create_cb(struct ceph_mds_client *mdsc,
+                                 struct ceph_mds_request *req)
+{
+	int result = req->r_err ? req->r_err :
+			le32_to_cpu(req->r_reply_info.head->result);
+
+	mapping_set_error(req->r_parent->i_mapping, result);
+
+	if (result) {
+		struct dentry *dentry = req->r_dentry;
+		int pathlen;
+		u64 base;
+		char *path = ceph_mdsc_build_path(req->r_dentry, &pathlen,
+						  &base, 0);
+
+		ceph_dir_clear_complete(req->r_parent);
+		if (!d_unhashed(dentry))
+			d_drop(dentry);
+
+		/* FIXME: start returning I/O errors on all accesses? */
+		pr_warn("ceph: async create failure path=(%llx)%s result=%d!\n",
+			base, IS_ERR(path) ? "<<bad>>" : path, result);
+		ceph_mdsc_free_path(path, pathlen);
+	}
+
+	if (req->r_target_inode) {
+		struct ceph_inode_info *ci = ceph_inode(req->r_target_inode);
+		u64 ino = ceph_vino(req->r_target_inode).ino;
+
+		if (req->r_deleg_ino != ino)
+			pr_warn("%s: inode number mismatch! err=%d deleg_ino=0x%llx target=0x%llx\n",
+				__func__, req->r_err, req->r_deleg_ino, ino);
+		mapping_set_error(req->r_target_inode->i_mapping, result);
+
+		spin_lock(&ci->i_ceph_lock);
+		if (ci->i_ceph_flags & CEPH_I_ASYNC_CREATE) {
+			ci->i_ceph_flags &= ~CEPH_I_ASYNC_CREATE;
+			wake_up_bit(&ci->i_ceph_flags, CEPH_ASYNC_CREATE_BIT);
+		}
+		spin_unlock(&ci->i_ceph_lock);
+	} else {
+		pr_warn("%s: no req->r_target_inode for 0x%llx\n", __func__,
+			req->r_deleg_ino);
+	}
+	ceph_put_cap_refs(ceph_inode(req->r_parent),
+			  CEPH_CAP_FILE_EXCL | CEPH_CAP_DIR_CREATE);
+}
+
+static int ceph_finish_async_create(struct inode *dir, struct dentry *dentry,
+				    struct file *file, umode_t mode,
+				    struct ceph_mds_request *req,
+				    struct ceph_acl_sec_ctx *as_ctx,
+				    struct ceph_file_layout *lo)
+{
+	int ret;
+	char xattr_buf[4];
+	struct ceph_mds_reply_inode in = { };
+	struct ceph_mds_reply_info_in iinfo = { .in = &in };
+	struct ceph_inode_info *ci = ceph_inode(dir);
+	struct inode *inode;
+	struct timespec64 now;
+	struct ceph_vino vino = { .ino = req->r_deleg_ino,
+				  .snap = CEPH_NOSNAP };
+
+	ktime_get_real_ts64(&now);
+
+	inode = ceph_get_inode(dentry->d_sb, vino);
+	if (IS_ERR(inode))
+		return PTR_ERR(inode);
+
+	iinfo.inline_version = CEPH_INLINE_NONE;
+	iinfo.change_attr = 1;
+	ceph_encode_timespec64(&iinfo.btime, &now);
+
+	iinfo.xattr_len = ARRAY_SIZE(xattr_buf);
+	iinfo.xattr_data = xattr_buf;
+	memset(iinfo.xattr_data, 0, iinfo.xattr_len);
+
+	in.ino = cpu_to_le64(vino.ino);
+	in.snapid = cpu_to_le64(CEPH_NOSNAP);
+	in.version = cpu_to_le64(1);	// ???
+	in.cap.caps = in.cap.wanted = cpu_to_le32(CEPH_CAP_ALL_FILE);
+	in.cap.cap_id = cpu_to_le64(1);
+	in.cap.realm = cpu_to_le64(ci->i_snap_realm->ino);
+	in.cap.flags = CEPH_CAP_FLAG_AUTH;
+	in.ctime = in.mtime = in.atime = iinfo.btime;
+	in.mode = cpu_to_le32((u32)mode);
+	in.truncate_seq = cpu_to_le32(1);
+	in.truncate_size = cpu_to_le64(-1ULL);
+	in.xattr_version = cpu_to_le64(1);
+	in.uid = cpu_to_le32(from_kuid(&init_user_ns, current_fsuid()));
+	in.gid = cpu_to_le32(from_kgid(&init_user_ns, dir->i_mode & S_ISGID ?
+				dir->i_gid : current_fsgid()));
+	in.nlink = cpu_to_le32(1);
+	in.max_size = cpu_to_le64(lo->stripe_unit);
+
+	ceph_file_layout_to_legacy(lo, &in.layout);
+
+	ret = ceph_fill_inode(inode, NULL, &iinfo, NULL, req->r_session,
+			      req->r_fmode, NULL);
+	if (ret) {
+		dout("%s failed to fill inode: %d\n", __func__, ret);
+		ceph_dir_clear_complete(dir);
+		if (!d_unhashed(dentry))
+			d_drop(dentry);
+		if (inode->i_state & I_NEW)
+			discard_new_inode(inode);
+	} else {
+		struct dentry *dn;
+
+		dout("%s d_adding new inode 0x%llx to 0x%lx/%s\n", __func__,
+			vino.ino, dir->i_ino, dentry->d_name.name);
+		ceph_dir_clear_ordered(dir);
+		ceph_init_inode_acls(inode, as_ctx);
+		if (inode->i_state & I_NEW) {
+			/*
+			 * If it's not I_NEW, then someone created this before
+			 * we got here. Assume the server is aware of it at
+			 * that point and don't worry about setting
+			 * CEPH_I_ASYNC_CREATE.
+			 */
+			ceph_inode(inode)->i_ceph_flags = CEPH_I_ASYNC_CREATE;
+			unlock_new_inode(inode);
+		}
+		if (d_in_lookup(dentry) || d_really_is_negative(dentry)) {
+			if (!d_unhashed(dentry))
+				d_drop(dentry);
+			dn = d_splice_alias(inode, dentry);
+			WARN_ON_ONCE(dn && dn != dentry);
+		}
+		file->f_mode |= FMODE_CREATED;
+		ret = finish_open(file, dentry, ceph_open);
+	}
+	return ret;
+}
+
 /*
  * Do a lookup + open with a single request.  If we get a non-existent
  * file or symlink, return 1 so the VFS can retry.
@@ -460,6 +650,7 @@  int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
 	struct ceph_mds_request *req;
 	struct dentry *dn;
 	struct ceph_acl_sec_ctx as_ctx = {};
+	bool try_async = ceph_test_mount_opt(fsc, ASYNC_DIROPS);
 	int mask;
 	int err;
 
@@ -483,7 +674,7 @@  int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
 		/* If it's not being looked up, it's negative */
 		return -ENOENT;
 	}
-
+retry:
 	/* do the open */
 	req = prepare_open_request(dir->i_sb, flags, mode);
 	if (IS_ERR(req)) {
@@ -492,28 +683,47 @@  int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
 	}
 	req->r_dentry = dget(dentry);
 	req->r_num_caps = 2;
+	mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
+	if (ceph_security_xattr_wanted(dir))
+		mask |= CEPH_CAP_XATTR_SHARED;
+	req->r_args.open.mask = cpu_to_le32(mask);
+	req->r_parent = dir;
+
 	if (flags & O_CREAT) {
+		struct ceph_file_layout lo;
+
 		req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
 		req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 		if (as_ctx.pagelist) {
 			req->r_pagelist = as_ctx.pagelist;
 			as_ctx.pagelist = NULL;
 		}
+		if (try_async && try_prep_async_create(dir, dentry, &lo,
+						       &req->r_deleg_ino)) {
+			set_bit(CEPH_MDS_R_ASYNC, &req->r_req_flags);
+			req->r_args.open.flags |= cpu_to_le32(CEPH_O_EXCL);
+			req->r_callback = ceph_async_create_cb;
+			err = ceph_mdsc_submit_request(mdsc, dir, req);
+			if (!err) {
+				err = ceph_finish_async_create(dir, dentry,
+							file, mode, req,
+							&as_ctx, &lo);
+			} else if (err == -EJUKEBOX) {
+				ceph_mdsc_put_request(req);
+				try_async = false;
+				goto retry;
+			}
+			goto out_req;
+		}
 	}
 
-       mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
-       if (ceph_security_xattr_wanted(dir))
-               mask |= CEPH_CAP_XATTR_SHARED;
-       req->r_args.open.mask = cpu_to_le32(mask);
-
-	req->r_parent = dir;
 	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
 	err = ceph_mdsc_do_request(mdsc,
 				   (flags & (O_CREAT|O_TRUNC)) ? dir : NULL,
 				   req);
 	err = ceph_handle_snapdir(req, dentry, err);
 	if (err)
-		goto out_req;
+		goto out_fmode;
 
 	if ((flags & O_CREAT) && !req->r_reply_info.head->is_dentry)
 		err = ceph_handle_notrace_create(dir, dentry);
@@ -527,7 +737,7 @@  int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
 		dn = NULL;
 	}
 	if (err)
-		goto out_req;
+		goto out_fmode;
 	if (dn || d_really_is_negative(dentry) || d_is_symlink(dentry)) {
 		/* make vfs retry on splice, ENOENT, or symlink */
 		dout("atomic_open finish_no_open on dn %p\n", dn);
@@ -543,9 +753,10 @@  int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
 		}
 		err = finish_open(file, dentry, ceph_open);
 	}
-out_req:
+out_fmode:
 	if (!req->r_err && req->r_target_inode)
 		ceph_put_fmode(ceph_inode(req->r_target_inode), req->r_fmode);
+out_req:
 	ceph_mdsc_put_request(req);
 out_ctx:
 	ceph_release_acl_sec_ctx(&as_ctx);
diff --git a/include/linux/ceph/ceph_fs.h b/include/linux/ceph/ceph_fs.h
index 91d09cf37649..e035c5194005 100644
--- a/include/linux/ceph/ceph_fs.h
+++ b/include/linux/ceph/ceph_fs.h
@@ -659,6 +659,9 @@  int ceph_flags_to_mode(int flags);
 #define CEPH_CAP_ANY      (CEPH_CAP_ANY_RD | CEPH_CAP_ANY_EXCL | \
 			   CEPH_CAP_ANY_FILE_WR | CEPH_CAP_FILE_LAZYIO | \
 			   CEPH_CAP_PIN)
+#define CEPH_CAP_ALL_FILE (CEPH_CAP_PIN | CEPH_CAP_ANY_SHARED | \
+			   CEPH_CAP_AUTH_EXCL | CEPH_CAP_XATTR_EXCL | \
+			   CEPH_CAP_ANY_FILE_RD | CEPH_CAP_ANY_FILE_WR)
 
 #define CEPH_CAP_LOCKS (CEPH_LOCK_IFILE | CEPH_LOCK_IAUTH | CEPH_LOCK_ILINK | \
 			CEPH_LOCK_IXATTR)