--- zzzz-none-000/linux-3.10.107/fs/ceph/export.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/fs/ceph/export.c 2021-02-04 17:41:59.000000000 +0000 @@ -8,23 +8,6 @@ #include "mds_client.h" /* - * NFS export support - * - * NFS re-export of a ceph mount is, at present, only semireliable. - * The basic issue is that the Ceph architectures doesn't lend itself - * well to generating filehandles that will remain valid forever. - * - * So, we do our best. If you're lucky, your inode will be in the - * client's cache. If it's not, and you have a connectable fh, then - * the MDS server may be able to find it for you. Otherwise, you get - * ESTALE. - * - * There are ways to this more reliable, but in the non-connectable fh - * case, we won't every work perfectly, and in the connectable case, - * some changes are needed on the MDS side to work better. - */ - -/* * Basic fh */ struct ceph_nfs_fh { @@ -32,22 +15,12 @@ } __attribute__ ((packed)); /* - * Larger 'connectable' fh that includes parent ino and name hash. - * Use this whenever possible, as it works more reliably. + * Larger fh that includes parent ino. */ struct ceph_nfs_confh { u64 ino, parent_ino; - u32 parent_name_hash; } __attribute__ ((packed)); -/* - * The presence of @parent_inode here tells us whether NFS wants a - * connectable file handle. However, we want to make a connectionable - * file handle unconditionally so that the MDS gets as much of a hint - * as possible. That means we only use @parent_dentry to indicate - * whether nfsd wants a connectable fh, and whether we should indicate - * failure from a too-small @max_len. - */ static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len, struct inode *parent_inode) { @@ -56,54 +29,36 @@ struct ceph_nfs_confh *cfh = (void *)rawfh; int connected_handle_length = sizeof(*cfh)/4; int handle_length = sizeof(*fh)/4; - struct dentry *dentry; - struct dentry *parent; /* don't re-export snaps */ if (ceph_snap(inode) != CEPH_NOSNAP) return -EINVAL; - dentry = d_find_alias(inode); + 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 we found an alias, generate a connectable fh */ - if (*max_len >= connected_handle_length && dentry) { - dout("encode_fh %p connectable\n", dentry); - spin_lock(&dentry->d_lock); - parent = dentry->d_parent; + 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->d_inode); - cfh->parent_name_hash = ceph_dentry_hash(parent->d_inode, - dentry); + cfh->parent_ino = ceph_ino(parent_inode); *max_len = connected_handle_length; - type = 2; - spin_unlock(&dentry->d_lock); - } else if (*max_len >= handle_length) { - if (parent_inode) { - /* nfsd wants connectable */ - *max_len = connected_handle_length; - type = FILEID_INVALID; - } else { - dout("encode_fh %p\n", dentry); - fh->ino = ceph_ino(inode); - *max_len = handle_length; - type = 1; - } + 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_INVALID; + type = FILEID_INO32_GEN; } - if (dentry) - dput(dentry); return type; } -/* - * convert regular fh to dentry - * - * FIXME: we should try harder by querying the mds for the ino. - */ -static struct dentry *__fh_to_dentry(struct super_block *sb, - struct ceph_nfs_fh *fh, int fh_len) +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; @@ -111,11 +66,7 @@ struct ceph_vino vino; int err; - if (fh_len < sizeof(*fh) / 4) - return ERR_PTR(-ESTALE); - - dout("__fh_to_dentry %llx\n", fh->ino); - vino.ino = fh->ino; + vino.ino = ino; vino.snap = CEPH_NOSNAP; inode = ceph_find_inode(sb, vino); if (!inode) { @@ -139,139 +90,161 @@ dentry = d_obtain_alias(inode); if (IS_ERR(dentry)) { - pr_err("fh_to_dentry %llx -- inode %p but ENOMEM\n", - fh->ino, inode); iput(inode); return dentry; } err = ceph_init_dentry(dentry); if (err < 0) { - iput(inode); + dput(dentry); return ERR_PTR(err); } - dout("__fh_to_dentry %llx %p dentry %p\n", fh->ino, inode, dentry); + dout("__fh_to_dentry %llx %p dentry %p\n", ino, inode, dentry); return dentry; } /* - * convert connectable fh to dentry + * convert regular fh to dentry */ -static struct dentry *__cfh_to_dentry(struct super_block *sb, - struct ceph_nfs_confh *cfh, int fh_len) +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; struct dentry *dentry; - struct ceph_vino vino; int err; - if (fh_len < sizeof(*cfh) / 4) - return ERR_PTR(-ESTALE); - - dout("__cfh_to_dentry %llx (%llx/%x)\n", - cfh->ino, cfh->parent_ino, cfh->parent_name_hash); - - vino.ino = cfh->ino; - vino.snap = CEPH_NOSNAP; - inode = ceph_find_inode(sb, vino); - if (!inode) { - struct ceph_mds_request *req; - - req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LOOKUPHASH, - USE_ANY_MDS); - if (IS_ERR(req)) - return ERR_CAST(req); - - req->r_ino1 = vino; - req->r_ino2.ino = cfh->parent_ino; - req->r_ino2.snap = CEPH_NOSNAP; - req->r_path2 = kmalloc(16, GFP_NOFS); - snprintf(req->r_path2, 16, "%d", cfh->parent_name_hash); - 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(err ? err : -ESTALE); - } + 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, + }; + } + 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(-ENOENT); dentry = d_obtain_alias(inode); if (IS_ERR(dentry)) { - pr_err("cfh_to_dentry %llx -- inode %p but ENOMEM\n", - cfh->ino, inode); iput(inode); return dentry; } err = ceph_init_dentry(dentry); if (err < 0) { - iput(inode); + dput(dentry); return ERR_PTR(err); } - dout("__cfh_to_dentry %llx %p dentry %p\n", cfh->ino, inode, dentry); + dout("__get_parent ino %llx parent %p ino %llx.%llx\n", + child ? ceph_ino(d_inode(child)) : ino, + dentry, ceph_vinop(inode)); return dentry; } -static struct dentry *ceph_fh_to_dentry(struct super_block *sb, struct fid *fid, - int fh_len, int fh_type) +static struct dentry *ceph_get_parent(struct dentry *child) { - if (fh_type == 1) - return __fh_to_dentry(sb, (struct ceph_nfs_fh *)fid->raw, - fh_len); - else - return __cfh_to_dentry(sb, (struct ceph_nfs_confh *)fid->raw, - fh_len); + /* 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); } /* - * get parent, if possible. - * - * FIXME: we could do better by querying the mds to discover the - * parent. + * convert regular fh to parent */ static struct dentry *ceph_fh_to_parent(struct super_block *sb, - struct fid *fid, + struct fid *fid, int fh_len, int fh_type) { struct ceph_nfs_confh *cfh = (void *)fid->raw; - struct ceph_vino vino; - struct inode *inode; struct dentry *dentry; - int err; - if (fh_type == 1) - return ERR_PTR(-ESTALE); + if (fh_type != FILEID_INO32_GEN_PARENT) + return NULL; if (fh_len < sizeof(*cfh) / 4) - return ERR_PTR(-ESTALE); + return NULL; - pr_debug("fh_to_parent %llx/%d\n", cfh->parent_ino, - cfh->parent_name_hash); + dout("fh_to_parent %llx\n", cfh->parent_ino); + dentry = __get_parent(sb, NULL, cfh->ino); + if (IS_ERR(dentry) && PTR_ERR(dentry) == -ENOENT) + dentry = __fh_to_dentry(sb, cfh->parent_ino); + return dentry; +} - vino.ino = cfh->ino; - vino.snap = CEPH_NOSNAP; - inode = ceph_find_inode(sb, vino); - if (!inode) - return ERR_PTR(-ESTALE); +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; - dentry = d_obtain_alias(inode); - if (IS_ERR(dentry)) { - pr_err("fh_to_parent %llx -- inode %p but ENOMEM\n", - cfh->ino, inode); - iput(inode); - return dentry; - } - err = ceph_init_dentry(dentry); - if (err < 0) { - iput(inode); - return ERR_PTR(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); + + mutex_lock(&d_inode(parent)->i_mutex); + + 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_num_caps = 2; + err = ceph_mdsc_do_request(mdsc, NULL, req); + + mutex_unlock(&d_inode(parent)->i_mutex); + + 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); } - dout("fh_to_parent %llx %p dentry %p\n", cfh->ino, inode, dentry); - return dentry; + + 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, };