diff options
Diffstat (limited to 'fs/ceph/export.c')
| -rw-r--r-- | fs/ceph/export.c | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/fs/ceph/export.c b/fs/ceph/export.c new file mode 100644 index 000000000..4cfe1154d --- /dev/null +++ b/fs/ceph/export.c @@ -0,0 +1,248 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/ceph/ceph_debug.h> + +#include <linux/exportfs.h> +#include <linux/slab.h> +#include <asm/unaligned.h> + +#include "super.h" +#include "mds_client.h" + +/* + * Basic fh + */ +struct ceph_nfs_fh { + u64 ino; +} __attribute__ ((packed)); + +/* + * Larger fh that includes parent ino. + */ +struct ceph_nfs_confh { + u64 ino, parent_ino; +} __attribute__ ((packed)); + +static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len, + struct inode *parent_inode) +{ + 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; + + if (parent_inode && (*max_len < connected_handle_length)) { + *max_len = connected_handle_length; + return FILEID_INVALID; + } else if (*max_len < handle_length) { + *max_len = handle_length; + return FILEID_INVALID; + } + + if (parent_inode) { + dout("encode_fh %llx with parent %llx\n", + ceph_ino(inode), ceph_ino(parent_inode)); + cfh->ino = ceph_ino(inode); + cfh->parent_ino = ceph_ino(parent_inode); + *max_len = connected_handle_length; + type = FILEID_INO32_GEN_PARENT; + } else { + dout("encode_fh %llx\n", ceph_ino(inode)); + fh->ino = ceph_ino(inode); + *max_len = handle_length; + type = FILEID_INO32_GEN; + } + return type; +} + +static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino) +{ + struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc; + struct inode *inode; + struct ceph_vino vino; + int err; + + vino.ino = ino; + vino.snap = CEPH_NOSNAP; + inode = ceph_find_inode(sb, vino); + if (!inode) { + struct ceph_mds_request *req; + int mask; + + 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.getattr.mask = cpu_to_le32(mask); + + req->r_ino1 = vino; + req->r_num_caps = 1; + err = ceph_mdsc_do_request(mdsc, NULL, req); + inode = req->r_target_inode; + 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 d_obtain_alias(inode); +} + +/* + * convert regular fh to dentry + */ +static struct dentry *ceph_fh_to_dentry(struct super_block *sb, + struct fid *fid, + int fh_len, int fh_type) +{ + struct ceph_nfs_fh *fh = (void *)fid->raw; + + if (fh_type != FILEID_INO32_GEN && + fh_type != FILEID_INO32_GEN_PARENT) + return NULL; + if (fh_len < sizeof(*fh) / 4) + return NULL; + + dout("fh_to_dentry %llx\n", fh->ino); + return __fh_to_dentry(sb, fh->ino); +} + +static struct dentry *__get_parent(struct super_block *sb, + struct dentry *child, u64 ino) +{ + struct ceph_mds_client *mdsc = ceph_sb_to_client(sb)->mdsc; + struct ceph_mds_request *req; + struct inode *inode; + int mask; + int err; + + req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPPARENT, + USE_ANY_MDS); + if (IS_ERR(req)) + return ERR_CAST(req); + + if (child) { + req->r_inode = d_inode(child); + ihold(d_inode(child)); + } else { + req->r_ino1 = (struct ceph_vino) { + .ino = ino, + .snap = CEPH_NOSNAP, + }; + } + + 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_num_caps = 1; + err = ceph_mdsc_do_request(mdsc, NULL, req); + if (err) { + ceph_mdsc_put_request(req); + return ERR_PTR(err); + } + + inode = req->r_target_inode; + if (inode) + ihold(inode); + ceph_mdsc_put_request(req); + if (!inode) + return ERR_PTR(-ENOENT); + + return d_obtain_alias(inode); +} + +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); +} + +/* + * convert regular fh to parent + */ +static struct dentry *ceph_fh_to_parent(struct super_block *sb, + struct fid *fid, + int fh_len, int fh_type) +{ + struct ceph_nfs_confh *cfh = (void *)fid->raw; + struct dentry *dentry; + + if (fh_type != FILEID_INO32_GEN_PARENT) + return NULL; + if (fh_len < sizeof(*cfh) / 4) + return NULL; + + dout("fh_to_parent %llx\n", cfh->parent_ino); + dentry = __get_parent(sb, NULL, cfh->ino); + if (unlikely(dentry == ERR_PTR(-ENOENT))) + dentry = __fh_to_dentry(sb, cfh->parent_ino); + return dentry; +} + +static int ceph_get_name(struct dentry *parent, char *name, + struct dentry *child) +{ + struct ceph_mds_client *mdsc; + struct ceph_mds_request *req; + int err; + + mdsc = ceph_inode_to_client(d_inode(child))->mdsc; + req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPNAME, + USE_ANY_MDS); + if (IS_ERR(req)) + return PTR_ERR(req); + + inode_lock(d_inode(parent)); + + req->r_inode = d_inode(child); + ihold(d_inode(child)); + 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); + req->r_num_caps = 2; + err = ceph_mdsc_do_request(mdsc, NULL, req); + + inode_unlock(d_inode(parent)); + + if (!err) { + struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info; + 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); + } else { + dout("get_name %p ino %llx.%llx err %d\n", + child, ceph_vinop(d_inode(child)), err); + } + + ceph_mdsc_put_request(req); + return err; +} + +const struct export_operations ceph_export_ops = { + .encode_fh = ceph_encode_fh, + .fh_to_dentry = ceph_fh_to_dentry, + .fh_to_parent = ceph_fh_to_parent, + .get_parent = ceph_get_parent, + .get_name = ceph_get_name, +}; |