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 enable_async_dirops module option,
along with async unlinks, and on the server supporting the necessary
CephFS feature bit.
Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
---
fs/ceph/file.c | 196 +++++++++++++++++++++++++++++++++--
include/linux/ceph/ceph_fs.h | 3 +
2 files changed, 190 insertions(+), 9 deletions(-)
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index b44ccbc85fe4..2742417fa5ec 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -448,6 +448,169 @@ 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,
+ unsigned long *pino)
+{
+ struct ceph_inode_info *ci = ceph_inode(dir);
+ bool ret = false;
+ unsigned long 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;
+
+ /* Use LOOKUP_RCU since we're under i_ceph_lock */
+ if (!__ceph_dir_is_complete(ci) &&
+ !dentry_lease_is_valid(dentry, LOOKUP_RCU))
+ goto no_async;
+
+ if (!(__ceph_caps_issued(ci, NULL) &
+ (CEPH_CAP_FILE_EXCL | CEPH_CAP_DIR_CREATE)))
+ 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)
+{
+ mapping_set_error(req->r_parent->i_mapping, req->r_err);
+
+ 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%lx target=0x%llx\n",
+ __func__, req->r_err, req->r_deleg_ino, ino);
+ mapping_set_error(req->r_target_inode->i_mapping, req->r_err);
+
+ 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%lx\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);
+ 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 +623,7 @@ 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 = enable_async_dirops;
int mask;
int err;
@@ -492,28 +656,41 @@ 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_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);
+ 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 +704,7 @@ 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 +720,10 @@ 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)
