ceph: add a new flag to indicate whether parent is locked

struct ceph_mds_request has an r_locked_dir pointer, which is set to
indicate the parent inode and that its i_rwsem is locked.  In some
critical places, we need to be able to indicate the parent inode to the
request handling code, even when its i_rwsem may not be locked.

Most of the code that operates on r_locked_dir doesn't require that the
i_rwsem be locked. We only really need it to handle manipulation of the
dcache. The rest (filling of the inode, updating dentry leases, etc.)
already has its own locking.

Add a new r_req_flags bit that indicates whether the parent is locked
when doing the request, and rename the pointer to "r_parent". For now,
all the places that set r_parent also set this flag, but that will
change in a later patch.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
This commit is contained in:
Jeff Layton 2017-01-31 10:28:26 -05:00 committed by Ilya Dryomov
parent bc2de10dc4
commit 3dd69aabce
6 changed files with 39 additions and 28 deletions

View File

@ -752,7 +752,8 @@ static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
mask |= CEPH_CAP_XATTR_SHARED;
req->r_args.getattr.mask = cpu_to_le32(mask);
req->r_locked_dir = dir;
req->r_parent = dir;
set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
err = ceph_mdsc_do_request(mdsc, NULL, req);
err = ceph_handle_snapdir(req, dentry, err);
dentry = ceph_finish_lookup(req, dentry, err);
@ -813,7 +814,8 @@ static int ceph_mknod(struct inode *dir, struct dentry *dentry,
}
req->r_dentry = dget(dentry);
req->r_num_caps = 2;
req->r_locked_dir = dir;
req->r_parent = dir;
set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
req->r_args.mknod.mode = cpu_to_le32(mode);
req->r_args.mknod.rdev = cpu_to_le32(rdev);
req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
@ -864,7 +866,8 @@ static int ceph_symlink(struct inode *dir, struct dentry *dentry,
ceph_mdsc_put_request(req);
goto out;
}
req->r_locked_dir = dir;
req->r_parent = dir;
set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
req->r_dentry = dget(dentry);
req->r_num_caps = 2;
req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
@ -913,7 +916,8 @@ static int ceph_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
req->r_dentry = dget(dentry);
req->r_num_caps = 2;
req->r_locked_dir = dir;
req->r_parent = dir;
set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
req->r_args.mkdir.mode = cpu_to_le32(mode);
req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
@ -957,7 +961,8 @@ static int ceph_link(struct dentry *old_dentry, struct inode *dir,
req->r_dentry = dget(dentry);
req->r_num_caps = 2;
req->r_old_dentry = dget(old_dentry);
req->r_locked_dir = dir;
req->r_parent = dir;
set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
/* release LINK_SHARED on source inode (mds will lock it) */
@ -1023,7 +1028,8 @@ static int ceph_unlink(struct inode *dir, struct dentry *dentry)
}
req->r_dentry = dget(dentry);
req->r_num_caps = 2;
req->r_locked_dir = dir;
req->r_parent = dir;
set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
req->r_inode_drop = drop_caps_for_unlink(inode);
@ -1066,7 +1072,8 @@ static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry,
req->r_num_caps = 2;
req->r_old_dentry = dget(old_dentry);
req->r_old_dentry_dir = old_dir;
req->r_locked_dir = new_dir;
req->r_parent = new_dir;
set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
req->r_old_dentry_drop = CEPH_CAP_FILE_SHARED;
req->r_old_dentry_unless = CEPH_CAP_FILE_EXCL;
req->r_dentry_drop = CEPH_CAP_FILE_SHARED;

View File

@ -207,7 +207,8 @@ static int ceph_get_name(struct dentry *parent, char *name,
req->r_inode = d_inode(child);
ihold(d_inode(child));
req->r_ino2 = ceph_vino(d_inode(parent));
req->r_locked_dir = d_inode(parent);
req->r_parent = d_inode(parent);
set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
req->r_num_caps = 2;
err = ceph_mdsc_do_request(mdsc, NULL, req);

View File

@ -379,7 +379,8 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
mask |= CEPH_CAP_XATTR_SHARED;
req->r_args.open.mask = cpu_to_le32(mask);
req->r_locked_dir = dir; /* caller holds dir->i_mutex */
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);

View File

@ -1122,13 +1122,13 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req)
if (!rinfo->head->is_target && !rinfo->head->is_dentry) {
dout("fill_trace reply is empty!\n");
if (rinfo->head->result == 0 && req->r_locked_dir)
if (rinfo->head->result == 0 && req->r_parent)
ceph_invalidate_dir_request(req);
return 0;
}
if (rinfo->head->is_dentry) {
struct inode *dir = req->r_locked_dir;
struct inode *dir = req->r_parent;
if (dir) {
err = fill_inode(dir, NULL,
@ -1213,8 +1213,9 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req)
* ignore null lease/binding on snapdir ENOENT, or else we
* will have trouble splicing in the virtual snapdir later
*/
if (rinfo->head->is_dentry && req->r_locked_dir &&
!test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags) &&
if (rinfo->head->is_dentry &&
!test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags) &&
test_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags) &&
(rinfo->head->is_target || strncmp(req->r_dentry->d_name.name,
fsc->mount_options->snapdir_name,
req->r_dentry->d_name.len))) {
@ -1223,7 +1224,7 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req)
* mknod symlink mkdir : null -> new inode
* unlink : linked -> null
*/
struct inode *dir = req->r_locked_dir;
struct inode *dir = req->r_parent;
struct dentry *dn = req->r_dentry;
bool have_dir_cap, have_lease;
@ -1321,7 +1322,7 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req)
req->r_op == CEPH_MDS_OP_MKSNAP) &&
!test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags)) {
struct dentry *dn = req->r_dentry;
struct inode *dir = req->r_locked_dir;
struct inode *dir = req->r_parent;
/* fill out a snapdir LOOKUPSNAP dentry */
BUG_ON(!dn);

View File

@ -547,8 +547,8 @@ void ceph_mdsc_release_request(struct kref *kref)
ceph_put_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN);
iput(req->r_inode);
}
if (req->r_locked_dir)
ceph_put_cap_refs(ceph_inode(req->r_locked_dir), CEPH_CAP_PIN);
if (req->r_parent)
ceph_put_cap_refs(ceph_inode(req->r_parent), CEPH_CAP_PIN);
iput(req->r_target_inode);
if (req->r_dentry)
dput(req->r_dentry);
@ -735,7 +735,7 @@ static int __choose_mds(struct ceph_mds_client *mdsc,
rcu_read_lock();
parent = req->r_dentry->d_parent;
dir = req->r_locked_dir ? : d_inode_rcu(parent);
dir = req->r_parent ? : d_inode_rcu(parent);
if (!dir || dir->i_sb != mdsc->fsc->sb) {
/* not this fs or parent went negative */
@ -1894,7 +1894,7 @@ static struct ceph_msg *create_request_message(struct ceph_mds_client *mdsc,
int ret;
ret = set_request_path_attr(req->r_inode, req->r_dentry,
req->r_locked_dir, req->r_path1, req->r_ino1.ino,
req->r_parent, req->r_path1, req->r_ino1.ino,
&path1, &pathlen1, &ino1, &freepath1);
if (ret < 0) {
msg = ERR_PTR(ret);
@ -1956,7 +1956,7 @@ static struct ceph_msg *create_request_message(struct ceph_mds_client *mdsc,
mds, req->r_inode_drop, req->r_inode_unless, 0);
if (req->r_dentry_drop)
releases += ceph_encode_dentry_release(&p, req->r_dentry,
req->r_locked_dir, mds, req->r_dentry_drop,
req->r_parent, mds, req->r_dentry_drop,
req->r_dentry_unless);
if (req->r_old_dentry_drop)
releases += ceph_encode_dentry_release(&p, req->r_old_dentry,
@ -2095,14 +2095,14 @@ static int __prepare_send_request(struct ceph_mds_client *mdsc,
rhead->oldest_client_tid = cpu_to_le64(__get_oldest_tid(mdsc));
if (test_bit(CEPH_MDS_R_GOT_UNSAFE, &req->r_req_flags))
flags |= CEPH_MDS_FLAG_REPLAY;
if (req->r_locked_dir)
if (req->r_parent)
flags |= CEPH_MDS_FLAG_WANT_DENTRY;
rhead->flags = cpu_to_le32(flags);
rhead->num_fwd = req->r_num_fwd;
rhead->num_retry = req->r_attempts - 1;
rhead->ino = 0;
dout(" r_locked_dir = %p\n", req->r_locked_dir);
dout(" r_parent = %p\n", req->r_parent);
return 0;
}
@ -2282,11 +2282,11 @@ int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
dout("do_request on %p\n", req);
/* take CAP_PIN refs for r_inode, r_locked_dir, r_old_dentry */
/* take CAP_PIN refs for r_inode, r_parent, r_old_dentry */
if (req->r_inode)
ceph_get_cap_refs(ceph_inode(req->r_inode), CEPH_CAP_PIN);
if (req->r_locked_dir)
ceph_get_cap_refs(ceph_inode(req->r_locked_dir), CEPH_CAP_PIN);
if (req->r_parent)
ceph_get_cap_refs(ceph_inode(req->r_parent), CEPH_CAP_PIN);
if (req->r_old_dentry_dir)
ceph_get_cap_refs(ceph_inode(req->r_old_dentry_dir),
CEPH_CAP_PIN);
@ -2336,7 +2336,7 @@ int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
set_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags);
mutex_unlock(&req->r_fill_mutex);
if (req->r_locked_dir &&
if (req->r_parent &&
(req->r_op & CEPH_MDS_OP_WRITE))
ceph_invalidate_dir_request(req);
} else {
@ -2355,7 +2355,7 @@ int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
*/
void ceph_invalidate_dir_request(struct ceph_mds_request *req)
{
struct inode *inode = req->r_locked_dir;
struct inode *inode = req->r_parent;
dout("invalidate_dir_request %p (complete, lease(s))\n", inode);

View File

@ -202,7 +202,7 @@ struct ceph_mds_request {
char *r_path1, *r_path2;
struct ceph_vino r_ino1, r_ino2;
struct inode *r_locked_dir; /* dir (if any) i_mutex locked by vfs */
struct inode *r_parent; /* parent dir inode */
struct inode *r_target_inode; /* resulting inode */
#define CEPH_MDS_R_DIRECT_IS_HASH (1) /* r_direct_hash is valid */
@ -211,6 +211,7 @@ struct ceph_mds_request {
#define CEPH_MDS_R_GOT_SAFE (4) /* got a safe reply */
#define CEPH_MDS_R_GOT_RESULT (5) /* got a result */
#define CEPH_MDS_R_DID_PREPOPULATE (6) /* prepopulated readdir */
#define CEPH_MDS_R_PARENT_LOCKED (7) /* is r_parent->i_rwsem wlocked? */
unsigned long r_req_flags;
struct mutex r_fill_mutex;