@@ -21,18 +21,77 @@ struct ceph_nfs_confh {
u64 ino, parent_ino;
} __attribute__ ((packed));
+/*
+ * fh for snapped inode
+ */
+struct ceph_nfs_snapfh {
+ u64 ino;
+ u64 snapid;
+ u64 parent_ino;
+ u32 hash;
+} __attribute__ ((packed));
+
+static int ceph_encode_snapfh(struct inode *inode, u32 *rawfh, int *max_len,
+ struct inode *parent_inode)
+{
+ const static int snap_handle_length =
+ sizeof(struct ceph_nfs_snapfh) >> 2;
+ struct ceph_nfs_snapfh *sfh = (void *)rawfh;
+ u64 snapid = ceph_snap(inode);
+ int ret;
+ bool no_parent = true;
+
+ if (*max_len < snap_handle_length) {
+ *max_len = snap_handle_length;
+ ret = FILEID_INVALID;
+ goto out;
+ }
+
+ ret = -EINVAL;
+ if (snapid != CEPH_SNAPDIR) {
+ struct inode *dir;
+ struct dentry *dentry = d_find_alias(inode);
+ if (!dentry)
+ goto out;
+
+ rcu_read_lock();
+ dir = d_inode_rcu(dentry->d_parent);
+ if (ceph_snap(dir) != CEPH_SNAPDIR) {
+ sfh->parent_ino = ceph_ino(dir);
+ sfh->hash = ceph_dentry_hash(dir, dentry);
+ no_parent = false;
+ }
+ rcu_read_unlock();
+ dput(dentry);
+ }
+
+ if (no_parent) {
+ if (!S_ISDIR(inode->i_mode))
+ goto out;
+ sfh->parent_ino = sfh->ino;
+ sfh->hash = 0;
+ }
+ sfh->ino = ceph_ino(inode);
+ sfh->snapid = snapid;
+
+ *max_len = snap_handle_length;
+ ret = FILEID_BTRFS_WITH_PARENT;
+out:
+ dout("encode_snapfh %llx.%llx ret=%d\n", ceph_vinop(inode), ret);
+ return ret;
+}
+
static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len,
struct inode *parent_inode)
{
+ const static int handle_length =
+ sizeof(struct ceph_nfs_fh) >> 2;
+ const static int connected_handle_length =
+ sizeof(struct ceph_nfs_confh) >> 2;
int type;
- struct ceph_nfs_fh *fh = (void *)rawfh;
- struct ceph_nfs_confh *cfh = (void *)rawfh;
- int connected_handle_length = sizeof(*cfh)/4;
- int handle_length = sizeof(*fh)/4;
- /* don't re-export snaps */
if (ceph_snap(inode) != CEPH_NOSNAP)
- return -EINVAL;
+ return ceph_encode_snapfh(inode, rawfh, max_len, parent_inode);
if (parent_inode && (*max_len < connected_handle_length)) {
*max_len = connected_handle_length;
@@ -43,6 +102,7 @@ static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len,
}
if (parent_inode) {
+ struct ceph_nfs_confh *cfh = (void *)rawfh;
dout("encode_fh %llx with parent %llx\n",
ceph_ino(inode), ceph_ino(parent_inode));
cfh->ino = ceph_ino(inode);
@@ -50,6 +110,7 @@ static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len,
*max_len = connected_handle_length;
type = FILEID_INO32_GEN_PARENT;
} else {
+ struct ceph_nfs_fh *fh = (void *)rawfh;
dout("encode_fh %llx\n", ceph_ino(inode));
fh->ino = ceph_ino(inode);
*max_len = handle_length;
@@ -58,7 +119,7 @@ static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len,
return type;
}
-static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino)
+static struct inode *__lookup_inode(struct super_block *sb, u64 ino)
{
struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc;
struct inode *inode;
@@ -80,7 +141,7 @@ static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino)
mask = CEPH_STAT_CAP_INODE;
if (ceph_security_xattr_wanted(d_inode(sb->s_root)))
mask |= CEPH_CAP_XATTR_SHARED;
- req->r_args.getattr.mask = cpu_to_le32(mask);
+ req->r_args.lookupino.mask = cpu_to_le32(mask);
req->r_ino1 = vino;
req->r_num_caps = 1;
@@ -89,17 +150,101 @@ static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino)
if (inode)
ihold(inode);
ceph_mdsc_put_request(req);
- if (!inode)
- return ERR_PTR(-ESTALE);
- if (inode->i_nlink == 0) {
- iput(inode);
- return ERR_PTR(-ESTALE);
- }
}
+ return inode ? inode : ERR_PTR(-ESTALE);
+}
+static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino)
+{
+ struct inode *inode = __lookup_inode(sb, ino);
+ if (IS_ERR(inode))
+ return ERR_CAST(inode);
+ if (inode->i_nlink == 0) {
+ iput(inode);
+ return ERR_PTR(-ESTALE);
+ }
return d_obtain_alias(inode);
}
+static struct dentry *__snapfh_to_dentry(struct super_block *sb,
+ struct ceph_nfs_snapfh *sfh,
+ bool want_parent)
+{
+ struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc;
+ struct ceph_mds_request *req;
+ struct inode *inode;
+ struct ceph_vino vino;
+ int mask;
+ int err;
+ bool unlinked = false;
+
+ if (want_parent) {
+ vino.ino = sfh->parent_ino;
+ if (sfh->snapid == CEPH_SNAPDIR)
+ vino.snap = CEPH_NOSNAP;
+ else if (sfh->ino == sfh->parent_ino)
+ vino.snap = CEPH_SNAPDIR;
+ else
+ vino.snap = sfh->snapid;
+ } else {
+ vino.ino = sfh->ino;
+ vino.snap = sfh->snapid;
+ }
+ inode = ceph_find_inode(sb, vino);
+ if (inode)
+ return d_obtain_alias(inode);
+
+ req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPINO,
+ USE_ANY_MDS);
+ if (IS_ERR(req))
+ return ERR_CAST(req);
+
+ mask = CEPH_STAT_CAP_INODE;
+ if (ceph_security_xattr_wanted(d_inode(sb->s_root)))
+ mask |= CEPH_CAP_XATTR_SHARED;
+ req->r_args.lookupino.mask = cpu_to_le32(mask);
+ if (vino.snap < CEPH_NOSNAP) {
+ req->r_args.lookupino.snapid = cpu_to_le64(vino.snap);
+ if (!want_parent && sfh->ino != sfh->parent_ino) {
+ req->r_args.lookupino.parent =
+ cpu_to_le64(sfh->parent_ino);
+ req->r_args.lookupino.hash =
+ cpu_to_le32(sfh->hash);
+ }
+ }
+
+ req->r_ino1 = vino;
+ req->r_num_caps = 1;
+ err = ceph_mdsc_do_request(mdsc, NULL, req);
+ inode = req->r_target_inode;
+ if (inode) {
+ if (vino.snap == CEPH_SNAPDIR) {
+ if (inode->i_nlink == 0)
+ unlinked = true;
+ inode = ceph_get_snapdir(inode);
+ } else if (ceph_snap(inode) == vino.snap) {
+ ihold(inode);
+ } else {
+ /* mds does not support lookup snapped inode */
+ err = -EOPNOTSUPP;
+ inode = NULL;
+ }
+ }
+ ceph_mdsc_put_request(req);
+
+ if (want_parent) {
+ dout("snapfh_to_parent %llx.%llx\n err=%d\n",
+ vino.ino, vino.snap, err);
+ } else {
+ dout("snapfh_to_dentry %llx.%llx parent %llx hash %x err=%d",
+ vino.ino, vino.snap, sfh->parent_ino, sfh->hash, err);
+ }
+ if (!inode)
+ return ERR_PTR(-ESTALE);
+ /* see comments in ceph_get_parent() */
+ return unlinked ? d_obtain_root(inode) : d_obtain_alias(inode);
+}
+
/*
* convert regular fh to dentry
*/
@@ -109,6 +254,11 @@ static struct dentry *ceph_fh_to_dentry(struct super_block *sb,
{
struct ceph_nfs_fh *fh = (void *)fid->raw;
+ if (fh_type == FILEID_BTRFS_WITH_PARENT) {
+ struct ceph_nfs_snapfh *sfh = (void *)fid->raw;
+ return __snapfh_to_dentry(sb, sfh, false);
+ }
+
if (fh_type != FILEID_INO32_GEN &&
fh_type != FILEID_INO32_GEN_PARENT)
return NULL;
@@ -162,13 +312,49 @@ static struct dentry *__get_parent(struct super_block *sb,
static struct dentry *ceph_get_parent(struct dentry *child)
{
- /* don't re-export snaps */
- if (ceph_snap(d_inode(child)) != CEPH_NOSNAP)
- return ERR_PTR(-EINVAL);
-
- dout("get_parent %p ino %llx.%llx\n",
- child, ceph_vinop(d_inode(child)));
- return __get_parent(child->d_sb, child, 0);
+ struct inode *inode = d_inode(child);
+ struct dentry *dn;
+
+ if (ceph_snap(inode) != CEPH_NOSNAP) {
+ struct inode* dir;
+ bool unlinked = false;
+ /* do not support non-directory */
+ if (!d_is_dir(child)) {
+ dn = ERR_PTR(-EINVAL);
+ goto out;
+ }
+ dir = __lookup_inode(inode->i_sb, ceph_ino(inode));
+ if (IS_ERR(dir)) {
+ dn = ERR_CAST(dir);
+ goto out;
+ }
+ /* There can be multiple paths to access snapped inode.
+ * For simplicity, treat snapdir of head inode as parent */
+ if (ceph_snap(inode) != CEPH_SNAPDIR) {
+ struct inode *snapdir = ceph_get_snapdir(dir);
+ if (dir->i_nlink == 0)
+ unlinked = true;
+ iput(dir);
+ if (IS_ERR(snapdir)) {
+ dn = ERR_CAST(snapdir);
+ goto out;
+ }
+ dir = snapdir;
+ }
+ /* If directory has already been deleted, futher get_parent
+ * will fail. Do not mark snapdir dentry as disconnected,
+ * this prevent exportfs from doing futher get_parent. */
+ if (unlinked)
+ dn = d_obtain_root(dir);
+ else
+ dn = d_obtain_alias(dir);
+ } else {
+ dn = __get_parent(child->d_sb, child, 0);
+ }
+out:
+ dout("get_parent %p ino %llx.%llx err=%ld\n",
+ child, ceph_vinop(inode), (IS_ERR(dn) ? PTR_ERR(dn) : 0));
+ return dn;
}
/*
@@ -181,6 +367,11 @@ static struct dentry *ceph_fh_to_parent(struct super_block *sb,
struct ceph_nfs_confh *cfh = (void *)fid->raw;
struct dentry *dentry;
+ if (fh_type == FILEID_BTRFS_WITH_PARENT) {
+ struct ceph_nfs_snapfh *sfh = (void *)fid->raw;
+ return __snapfh_to_dentry(sb, sfh, true);
+ }
+
if (fh_type != FILEID_INO32_GEN_PARENT)
return NULL;
if (fh_len < sizeof(*cfh) / 4)
@@ -193,14 +384,115 @@ static struct dentry *ceph_fh_to_parent(struct super_block *sb,
return dentry;
}
+static int __get_snap_name(struct dentry *parent, char *name,
+ struct dentry *child)
+{
+ struct inode *inode = d_inode(child);
+ struct inode *dir = d_inode(parent);
+ struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+ struct ceph_mds_request *req = NULL;
+ char *last_name = NULL;
+ unsigned next_offset = 2;
+ int err = -EINVAL;
+
+ if (ceph_ino(inode) != ceph_ino(dir))
+ goto out;
+ if (ceph_snap(inode) == CEPH_SNAPDIR) {
+ if (ceph_snap(dir) == CEPH_NOSNAP) {
+ strcpy(name, fsc->mount_options->snapdir_name);
+ err = 0;
+ }
+ goto out;
+ }
+ if (ceph_snap(dir) != CEPH_SNAPDIR)
+ goto out;
+
+ while (1) {
+ struct ceph_mds_reply_info_parsed *rinfo;
+ struct ceph_mds_reply_dir_entry *rde;
+ int i;
+
+ req = ceph_mdsc_create_request(fsc->mdsc, CEPH_MDS_OP_LSSNAP,
+ USE_AUTH_MDS);
+ if (IS_ERR(req)) {
+ err = PTR_ERR(req);
+ req = NULL;
+ goto out;
+ }
+ err = ceph_alloc_readdir_reply_buffer(req, inode);
+ if (err)
+ goto out;
+
+ req->r_direct_mode = USE_AUTH_MDS;
+ req->r_readdir_offset = next_offset;
+ req->r_args.readdir.flags =
+ cpu_to_le16(CEPH_READDIR_REPLY_BITFLAGS);
+ if (last_name) {
+ req->r_path2 = last_name;
+ last_name = NULL;
+ }
+
+ req->r_inode = dir;
+ ihold(dir);
+ req->r_dentry = dget(parent);
+
+ inode_lock(dir);
+ err = ceph_mdsc_do_request(fsc->mdsc, NULL, req);
+ inode_unlock(dir);
+
+ if (err < 0)
+ goto out;
+
+ rinfo = &req->r_reply_info;
+ for (i = 0; i < rinfo->dir_nr; i++) {
+ rde = rinfo->dir_entries + i;
+ BUG_ON(!rde->inode.in);
+ if (ceph_snap(inode) ==
+ le64_to_cpu(rde->inode.in->snapid)) {
+ memcpy(name, rde->name, rde->name_len);
+ name[rde->name_len] = '\0';
+ err = 0;
+ goto out;
+ }
+ }
+
+ if (rinfo->dir_end)
+ break;
+
+ BUG_ON(rinfo->dir_nr <= 0);
+ rde = rinfo->dir_entries + (rinfo->dir_nr - 1);
+ next_offset += rinfo->dir_nr;
+ last_name = kstrndup(rde->name, rde->name_len, GFP_KERNEL);
+ if (!last_name) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ ceph_mdsc_put_request(req);
+ req = NULL;
+ }
+ err = -ENOENT;
+out:
+ if (req)
+ ceph_mdsc_put_request(req);
+ kfree(last_name);
+ dout("get_snap_name %p ino %llx.%llx err=%d\n",
+ child, ceph_vinop(inode), err);
+ return err;
+}
+
static int ceph_get_name(struct dentry *parent, char *name,
struct dentry *child)
{
struct ceph_mds_client *mdsc;
struct ceph_mds_request *req;
+ struct inode *inode = d_inode(child);
int err;
- mdsc = ceph_inode_to_client(d_inode(child))->mdsc;
+ if (ceph_snap(inode) != CEPH_NOSNAP)
+ return __get_snap_name(parent, name, child);
+
+ mdsc = ceph_inode_to_client(inode)->mdsc;
req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPNAME,
USE_ANY_MDS);
if (IS_ERR(req))
@@ -208,8 +500,8 @@ static int ceph_get_name(struct dentry *parent, char *name,
inode_lock(d_inode(parent));
- req->r_inode = d_inode(child);
- ihold(d_inode(child));
+ req->r_inode = inode;
+ ihold(inode);
req->r_ino2 = ceph_vino(d_inode(parent));
req->r_parent = d_inode(parent);
set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
@@ -223,10 +515,10 @@ static int ceph_get_name(struct dentry *parent, char *name,
memcpy(name, rinfo->dname, rinfo->dname_len);
name[rinfo->dname_len] = 0;
dout("get_name %p ino %llx.%llx name %s\n",
- child, ceph_vinop(d_inode(child)), name);
+ child, ceph_vinop(inode), name);
} else {
dout("get_name %p ino %llx.%llx err %d\n",
- child, ceph_vinop(d_inode(child)), err);
+ child, ceph_vinop(inode), err);
}
ceph_mdsc_put_request(req);
@@ -434,6 +434,12 @@ union ceph_mds_request_args {
__le64 length; /* num bytes to lock from start */
__u8 wait; /* will caller wait for lock to become available? */
} __attribute__ ((packed)) filelock_change;
+ struct {
+ __le32 mask; /* CEPH_CAP_* */
+ __le64 snapid;
+ __le64 parent;
+ __le32 hash;
+ } __attribute__ ((packed)) lookupino;
} __attribute__ ((packed));
#define CEPH_MDS_FLAG_REPLAY 1 /* this is a replayed op */
To support snapshot nfs re-export, we need a way to lookup snapped inode by file handle. For directory inode, snapped metadata are always stored together with head inode. Client just need to pass vinodeno_t to MDS. For non-directory inode, there can be multiple version of snapped inodes and they can be stored in different dirfrags. Besides vinodeno_t, client also need to tell mds from which dirfrag it got the snapped inode. Another problem of supporting snapshot nfs re-export is that there can be multiple paths to access a snapped inode. For example: mkdir -p d1/d2/d3 mkdir d1/.snap/s1 Paths 'd1/.snap/s1/d2/d3', 'd1/d2/.snap/_s1_<inode number of d1>/d3' and 'd1/d2/d3/.snap/_s1_<inode number of d1>' are all reference to the same snapped inode. For a given snapped inode, There is no convenient way to get the first form and the second form paths. For simplicity, ceph_get_parent() return snapdir. Furthermore, client may access snapshot of deleted directory. For example: mkdir -p d1/d2 mkdir d1/.snap/s1 open d1/.snap/s1/d2 rm -rf d1/d2 <nfs server restart> The path constucted by ceph_get_parent() and ceph_get_name() is '<inode of d2>/.snap/_s1_<inode number of d1>'. Futher lookup parent of <inode of d2> will fail. To workaround this case, this patch uses d_obtain_root() to get dentry for snapdir of deleted directory. snapdir dentry has no DCACHE_DISCONNECTED flag set, reconnect_path() stops when it reaches snapdir dentry. MDS patch is at https://github.com/ceph/ceph/pull/18942 Fixes: http://tracker.ceph.com/issues/22105 Signed-off-by: "Yan, Zheng" <zyan@redhat.com> --- fs/ceph/export.c | 344 +++++++++++++++++++++++++++++++++++++++---- include/linux/ceph/ceph_fs.h | 6 + 2 files changed, 324 insertions(+), 26 deletions(-) change since v1: handle deleted directory