From 11a60d159259dbadf9188534b508e5003769af61 Mon Sep 17 00:00:00 2001 From: Scott Mayhew Date: Mon, 9 Sep 2019 16:10:30 -0400 Subject: [PATCH] nfsd: add a "GetVersion" upcall for nfsdcld Add a "GetVersion" upcall to allow nfsd to determine the maximum upcall version that the nfsdcld userspace daemon supports. If the daemon responds with -EOPNOTSUPP, then we know it only supports v1. Signed-off-by: Scott Mayhew Signed-off-by: J. Bruce Fields --- fs/nfsd/nfs4recover.c | 167 ++++++++++++++++++++++++---------- include/uapi/linux/nfsd/cld.h | 11 ++- 2 files changed, 127 insertions(+), 51 deletions(-) diff --git a/fs/nfsd/nfs4recover.c b/fs/nfsd/nfs4recover.c index 87679557d0d6..58a61339d40c 100644 --- a/fs/nfsd/nfs4recover.c +++ b/fs/nfsd/nfs4recover.c @@ -59,8 +59,12 @@ struct nfsd4_client_tracking_ops { void (*remove)(struct nfs4_client *); int (*check)(struct nfs4_client *); void (*grace_done)(struct nfsd_net *); + uint8_t version; + size_t msglen; }; +static const struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops; + /* Globals */ static char user_recovery_dirname[PATH_MAX] = "/var/lib/nfs/v4recovery"; @@ -718,6 +722,8 @@ static const struct nfsd4_client_tracking_ops nfsd4_legacy_tracking_ops = { .remove = nfsd4_remove_clid_dir, .check = nfsd4_check_legacy_client, .grace_done = nfsd4_recdir_purge_old, + .version = 1, + .msglen = 0, }; /* Globals */ @@ -737,19 +743,24 @@ struct cld_upcall { struct list_head cu_list; struct cld_net *cu_net; struct completion cu_done; - struct cld_msg cu_msg; + union { + struct cld_msg_hdr cu_hdr; + struct cld_msg cu_msg; + } cu_u; }; static int -__cld_pipe_upcall(struct rpc_pipe *pipe, struct cld_msg *cmsg) +__cld_pipe_upcall(struct rpc_pipe *pipe, void *cmsg) { int ret; struct rpc_pipe_msg msg; - struct cld_upcall *cup = container_of(cmsg, struct cld_upcall, cu_msg); + struct cld_upcall *cup = container_of(cmsg, struct cld_upcall, cu_u); + struct nfsd_net *nn = net_generic(pipe->dentry->d_sb->s_fs_info, + nfsd_net_id); memset(&msg, 0, sizeof(msg)); msg.data = cmsg; - msg.len = sizeof(*cmsg); + msg.len = nn->client_tracking_ops->msglen; ret = rpc_queue_upcall(pipe, &msg); if (ret < 0) { @@ -765,7 +776,7 @@ out: } static int -cld_pipe_upcall(struct rpc_pipe *pipe, struct cld_msg *cmsg) +cld_pipe_upcall(struct rpc_pipe *pipe, void *cmsg) { int ret; @@ -809,7 +820,7 @@ __cld_pipe_inprogress_downcall(const struct cld_msg __user *cmsg, kfree(name.data); return -EFAULT; } - return sizeof(*cmsg); + return nn->client_tracking_ops->msglen; } return -EFAULT; } @@ -818,6 +829,7 @@ static ssize_t cld_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) { struct cld_upcall *tmp, *cup; + struct cld_msg_hdr __user *hdr = (struct cld_msg_hdr __user *)src; struct cld_msg __user *cmsg = (struct cld_msg __user *)src; uint32_t xid; struct nfsd_net *nn = net_generic(file_inode(filp)->i_sb->s_fs_info, @@ -825,14 +837,14 @@ cld_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) struct cld_net *cn = nn->cld_net; int16_t status; - if (mlen != sizeof(*cmsg)) { + if (mlen != nn->client_tracking_ops->msglen) { dprintk("%s: got %zu bytes, expected %zu\n", __func__, mlen, - sizeof(*cmsg)); + nn->client_tracking_ops->msglen); return -EINVAL; } /* copy just the xid so we can try to find that */ - if (copy_from_user(&xid, &cmsg->cm_xid, sizeof(xid)) != 0) { + if (copy_from_user(&xid, &hdr->cm_xid, sizeof(xid)) != 0) { dprintk("%s: error when copying xid from userspace", __func__); return -EFAULT; } @@ -842,7 +854,7 @@ cld_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) * list (for -EINPROGRESS, we just want to make sure the xid is * valid, not remove the upcall from the list) */ - if (get_user(status, &cmsg->cm_status)) { + if (get_user(status, &hdr->cm_status)) { dprintk("%s: error when copying status from userspace", __func__); return -EFAULT; } @@ -851,7 +863,7 @@ cld_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) cup = NULL; spin_lock(&cn->cn_lock); list_for_each_entry(tmp, &cn->cn_list, cu_list) { - if (get_unaligned(&tmp->cu_msg.cm_xid) == xid) { + if (get_unaligned(&tmp->cu_u.cu_hdr.cm_xid) == xid) { cup = tmp; if (status != -EINPROGRESS) list_del_init(&cup->cu_list); @@ -869,7 +881,7 @@ cld_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) if (status == -EINPROGRESS) return __cld_pipe_inprogress_downcall(cmsg, nn); - if (copy_from_user(&cup->cu_msg, src, mlen) != 0) + if (copy_from_user(&cup->cu_u.cu_msg, src, mlen) != 0) return -EFAULT; complete(&cup->cu_done); @@ -881,7 +893,7 @@ cld_pipe_destroy_msg(struct rpc_pipe_msg *msg) { struct cld_msg *cmsg = msg->data; struct cld_upcall *cup = container_of(cmsg, struct cld_upcall, - cu_msg); + cu_u.cu_msg); /* errno >= 0 means we got a downcall */ if (msg->errno >= 0) @@ -1012,9 +1024,10 @@ nfsd4_remove_cld_pipe(struct net *net) } static struct cld_upcall * -alloc_cld_upcall(struct cld_net *cn) +alloc_cld_upcall(struct nfsd_net *nn) { struct cld_upcall *new, *tmp; + struct cld_net *cn = nn->cld_net; new = kzalloc(sizeof(*new), GFP_KERNEL); if (!new) @@ -1024,20 +1037,20 @@ alloc_cld_upcall(struct cld_net *cn) restart_search: spin_lock(&cn->cn_lock); list_for_each_entry(tmp, &cn->cn_list, cu_list) { - if (tmp->cu_msg.cm_xid == cn->cn_xid) { + if (tmp->cu_u.cu_msg.cm_xid == cn->cn_xid) { cn->cn_xid++; spin_unlock(&cn->cn_lock); goto restart_search; } } init_completion(&new->cu_done); - new->cu_msg.cm_vers = CLD_UPCALL_VERSION; - put_unaligned(cn->cn_xid++, &new->cu_msg.cm_xid); + new->cu_u.cu_msg.cm_vers = nn->client_tracking_ops->version; + put_unaligned(cn->cn_xid++, &new->cu_u.cu_msg.cm_xid); new->cu_net = cn; list_add(&new->cu_list, &cn->cn_list); spin_unlock(&cn->cn_lock); - dprintk("%s: allocated xid %u\n", __func__, new->cu_msg.cm_xid); + dprintk("%s: allocated xid %u\n", __func__, new->cu_u.cu_msg.cm_xid); return new; } @@ -1066,20 +1079,20 @@ nfsd4_cld_create(struct nfs4_client *clp) if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) return; - cup = alloc_cld_upcall(cn); + cup = alloc_cld_upcall(nn); if (!cup) { ret = -ENOMEM; goto out_err; } - cup->cu_msg.cm_cmd = Cld_Create; - cup->cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len; - memcpy(cup->cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data, + cup->cu_u.cu_msg.cm_cmd = Cld_Create; + cup->cu_u.cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len; + memcpy(cup->cu_u.cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data, clp->cl_name.len); - ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg); + ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg); if (!ret) { - ret = cup->cu_msg.cm_status; + ret = cup->cu_u.cu_msg.cm_status; set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags); } @@ -1103,20 +1116,20 @@ nfsd4_cld_remove(struct nfs4_client *clp) if (!test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) return; - cup = alloc_cld_upcall(cn); + cup = alloc_cld_upcall(nn); if (!cup) { ret = -ENOMEM; goto out_err; } - cup->cu_msg.cm_cmd = Cld_Remove; - cup->cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len; - memcpy(cup->cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data, + cup->cu_u.cu_msg.cm_cmd = Cld_Remove; + cup->cu_u.cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len; + memcpy(cup->cu_u.cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data, clp->cl_name.len); - ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg); + ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg); if (!ret) { - ret = cup->cu_msg.cm_status; + ret = cup->cu_u.cu_msg.cm_status; clear_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags); } @@ -1145,21 +1158,21 @@ nfsd4_cld_check_v0(struct nfs4_client *clp) if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) return 0; - cup = alloc_cld_upcall(cn); + cup = alloc_cld_upcall(nn); if (!cup) { printk(KERN_ERR "NFSD: Unable to check client record on " "stable storage: %d\n", -ENOMEM); return -ENOMEM; } - cup->cu_msg.cm_cmd = Cld_Check; - cup->cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len; - memcpy(cup->cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data, + cup->cu_u.cu_msg.cm_cmd = Cld_Check; + cup->cu_u.cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len; + memcpy(cup->cu_u.cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data, clp->cl_name.len); - ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg); + ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg); if (!ret) { - ret = cup->cu_msg.cm_status; + ret = cup->cu_u.cu_msg.cm_status; set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags); } @@ -1223,16 +1236,16 @@ nfsd4_cld_grace_start(struct nfsd_net *nn) struct cld_upcall *cup; struct cld_net *cn = nn->cld_net; - cup = alloc_cld_upcall(cn); + cup = alloc_cld_upcall(nn); if (!cup) { ret = -ENOMEM; goto out_err; } - cup->cu_msg.cm_cmd = Cld_GraceStart; - ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg); + cup->cu_u.cu_msg.cm_cmd = Cld_GraceStart; + ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg); if (!ret) - ret = cup->cu_msg.cm_status; + ret = cup->cu_u.cu_msg.cm_status; free_cld_upcall(cup); out_err: @@ -1250,17 +1263,17 @@ nfsd4_cld_grace_done_v0(struct nfsd_net *nn) struct cld_upcall *cup; struct cld_net *cn = nn->cld_net; - cup = alloc_cld_upcall(cn); + cup = alloc_cld_upcall(nn); if (!cup) { ret = -ENOMEM; goto out_err; } - cup->cu_msg.cm_cmd = Cld_GraceDone; - cup->cu_msg.cm_u.cm_gracetime = (int64_t)nn->boot_time; - ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg); + cup->cu_u.cu_msg.cm_cmd = Cld_GraceDone; + cup->cu_u.cu_msg.cm_u.cm_gracetime = (int64_t)nn->boot_time; + ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg); if (!ret) - ret = cup->cu_msg.cm_status; + ret = cup->cu_u.cu_msg.cm_status; free_cld_upcall(cup); out_err: @@ -1279,16 +1292,16 @@ nfsd4_cld_grace_done(struct nfsd_net *nn) struct cld_upcall *cup; struct cld_net *cn = nn->cld_net; - cup = alloc_cld_upcall(cn); + cup = alloc_cld_upcall(nn); if (!cup) { ret = -ENOMEM; goto out_err; } - cup->cu_msg.cm_cmd = Cld_GraceDone; - ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg); + cup->cu_u.cu_msg.cm_cmd = Cld_GraceDone; + ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg); if (!ret) - ret = cup->cu_msg.cm_status; + ret = cup->cu_u.cu_msg.cm_status; free_cld_upcall(cup); out_err: @@ -1336,6 +1349,50 @@ cld_running(struct nfsd_net *nn) return pipe->nreaders || pipe->nwriters; } +static int +nfsd4_cld_get_version(struct nfsd_net *nn) +{ + int ret = 0; + struct cld_upcall *cup; + struct cld_net *cn = nn->cld_net; + uint8_t version; + + cup = alloc_cld_upcall(nn); + if (!cup) { + ret = -ENOMEM; + goto out_err; + } + cup->cu_u.cu_msg.cm_cmd = Cld_GetVersion; + ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg); + if (!ret) { + ret = cup->cu_u.cu_msg.cm_status; + if (ret) + goto out_free; + version = cup->cu_u.cu_msg.cm_u.cm_version; + dprintk("%s: userspace returned version %u\n", + __func__, version); + if (version < 1) + version = 1; + else if (version > CLD_UPCALL_VERSION) + version = CLD_UPCALL_VERSION; + + switch (version) { + case 1: + nn->client_tracking_ops = &nfsd4_cld_tracking_ops; + break; + default: + break; + } + } +out_free: + free_cld_upcall(cup); +out_err: + if (ret) + dprintk("%s: Unable to get version from userspace: %d\n", + __func__, ret); + return ret; +} + static int nfsd4_cld_tracking_init(struct net *net) { @@ -1368,10 +1425,14 @@ nfsd4_cld_tracking_init(struct net *net) goto err_remove; } + status = nfsd4_cld_get_version(nn); + if (status == -EOPNOTSUPP) + pr_warn("NFSD: nfsdcld GetVersion upcall failed. Please upgrade nfsdcld.\n"); + status = nfsd4_cld_grace_start(nn); if (status) { if (status == -EOPNOTSUPP) - printk(KERN_WARNING "NFSD: Please upgrade nfsdcld.\n"); + pr_warn("NFSD: nfsdcld GraceStart upcall failed. Please upgrade nfsdcld.\n"); nfs4_release_reclaim(nn); goto err_remove; } else @@ -1403,6 +1464,8 @@ static const struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops_v0 = { .remove = nfsd4_cld_remove, .check = nfsd4_cld_check_v0, .grace_done = nfsd4_cld_grace_done_v0, + .version = 1, + .msglen = sizeof(struct cld_msg), }; /* For newer nfsdcld's */ @@ -1413,6 +1476,8 @@ static const struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops = { .remove = nfsd4_cld_remove, .check = nfsd4_cld_check, .grace_done = nfsd4_cld_grace_done, + .version = 1, + .msglen = sizeof(struct cld_msg), }; /* upcall via usermodehelper */ @@ -1760,6 +1825,8 @@ static const struct nfsd4_client_tracking_ops nfsd4_umh_tracking_ops = { .remove = nfsd4_umh_cltrack_remove, .check = nfsd4_umh_cltrack_check, .grace_done = nfsd4_umh_cltrack_grace_done, + .version = 1, + .msglen = 0, }; int diff --git a/include/uapi/linux/nfsd/cld.h b/include/uapi/linux/nfsd/cld.h index b1e9de4f07d5..c5aad16d10c0 100644 --- a/include/uapi/linux/nfsd/cld.h +++ b/include/uapi/linux/nfsd/cld.h @@ -36,7 +36,8 @@ enum cld_command { Cld_Remove, /* remove record of this cm_id */ Cld_Check, /* is this cm_id allowed? */ Cld_GraceDone, /* grace period is complete */ - Cld_GraceStart, + Cld_GraceStart, /* grace start (upload client records) */ + Cld_GetVersion, /* query max supported upcall version */ }; /* representation of long-form NFSv4 client ID */ @@ -54,7 +55,15 @@ struct cld_msg { union { __s64 cm_gracetime; /* grace period start time */ struct cld_name cm_name; + __u8 cm_version; /* for getting max version */ } __attribute__((packed)) cm_u; } __attribute__((packed)); +struct cld_msg_hdr { + __u8 cm_vers; /* upcall version */ + __u8 cm_cmd; /* upcall command */ + __s16 cm_status; /* return code */ + __u32 cm_xid; /* transaction id */ +} __attribute__((packed)); + #endif /* !_NFSD_CLD_H */