diff options
| -rw-r--r-- | fs/smb/client/cifs_swn.c | 314 | ||||
| -rw-r--r-- | fs/smb/client/trace.h | 2 |
2 files changed, 262 insertions, 54 deletions
diff --git a/fs/smb/client/cifs_swn.c b/fs/smb/client/cifs_swn.c index 9753a432d099..9951817d0d7f 100644 --- a/fs/smb/client/cifs_swn.c +++ b/fs/smb/client/cifs_swn.c @@ -28,10 +28,54 @@ struct cifs_swn_reg { bool net_name_notify; bool share_name_notify; bool ip_notify; +}; - struct cifs_tcon *tcon; +struct cifs_swn_reg_info { + int id; + unsigned int ref_count; + const char *net_name; + const char *share_name; + bool net_name_notify; + bool share_name_notify; + bool ip_notify; }; +static void cifs_swn_snapshot_reg(struct cifs_swn_reg *swnreg, + struct cifs_swn_reg_info *info) +{ + info->id = swnreg->id; + info->ref_count = kref_read(&swnreg->ref_count); + info->net_name = swnreg->net_name; + info->share_name = swnreg->share_name; + info->net_name_notify = swnreg->net_name_notify; + info->share_name_notify = swnreg->share_name_notify; + info->ip_notify = swnreg->ip_notify; +} + +static int cifs_swn_dup_reg(struct cifs_swn_reg *swnreg, + struct cifs_swn_reg_info *info) +{ + cifs_swn_snapshot_reg(swnreg, info); + + info->net_name = kstrdup(swnreg->net_name, GFP_KERNEL); + if (!info->net_name) + return -ENOMEM; + + info->share_name = kstrdup(swnreg->share_name, GFP_KERNEL); + if (!info->share_name) { + kfree(info->net_name); + return -ENOMEM; + } + + return 0; +} + +static void cifs_swn_free_reg_info(struct cifs_swn_reg_info *info) +{ + kfree(info->net_name); + kfree(info->share_name); +} + static int cifs_swn_auth_info_krb(struct cifs_tcon *tcon, struct sk_buff *skb) { int ret; @@ -73,7 +117,8 @@ static int cifs_swn_auth_info_ntlm(struct cifs_tcon *tcon, struct sk_buff *skb) * The authentication information to connect to the witness service is bundled * into the message. */ -static int cifs_swn_send_register_message(struct cifs_swn_reg *swnreg) +static int cifs_swn_send_register_message(struct cifs_swn_reg_info *swnreg, + struct cifs_tcon *tcon) { struct sk_buff *skb; struct genlmsghdr *hdr; @@ -109,10 +154,10 @@ static int cifs_swn_send_register_message(struct cifs_swn_reg *swnreg) * told to switch to it (client move message). In these cases we unregister from the * server address and register to the new address when we receive the notification. */ - if (swnreg->tcon->ses->server->use_swn_dstaddr) - addr = &swnreg->tcon->ses->server->swn_dstaddr; + if (tcon->ses->server->use_swn_dstaddr) + addr = &tcon->ses->server->swn_dstaddr; else - addr = &swnreg->tcon->ses->server->dstaddr; + addr = &tcon->ses->server->dstaddr; ret = nla_put(skb, CIFS_GENL_ATTR_SWN_IP, sizeof(struct sockaddr_storage), addr); if (ret < 0) @@ -136,10 +181,10 @@ static int cifs_swn_send_register_message(struct cifs_swn_reg *swnreg) goto nlmsg_fail; } - authtype = cifs_select_sectype(swnreg->tcon->ses->server, swnreg->tcon->ses->sectype); + authtype = cifs_select_sectype(tcon->ses->server, tcon->ses->sectype); switch (authtype) { case Kerberos: - ret = cifs_swn_auth_info_krb(swnreg->tcon, skb); + ret = cifs_swn_auth_info_krb(tcon, skb); if (ret < 0) { cifs_dbg(VFS, "%s: Failed to get kerberos auth info: %d\n", __func__, ret); goto nlmsg_fail; @@ -147,7 +192,7 @@ static int cifs_swn_send_register_message(struct cifs_swn_reg *swnreg) break; case NTLMv2: case RawNTLMSSP: - ret = cifs_swn_auth_info_ntlm(swnreg->tcon, skb); + ret = cifs_swn_auth_info_ntlm(tcon, skb); if (ret < 0) { cifs_dbg(VFS, "%s: Failed to get NTLM auth info: %d\n", __func__, ret); goto nlmsg_fail; @@ -176,7 +221,8 @@ nlmsg_fail: /* * Sends an uregister message to the userspace daemon based on the registration */ -static int cifs_swn_send_unregister_message(struct cifs_swn_reg *swnreg) +static int cifs_swn_send_unregister_message(struct cifs_swn_reg_info *swnreg, + struct cifs_tcon *tcon) { struct sk_buff *skb; struct genlmsghdr *hdr; @@ -205,7 +251,7 @@ static int cifs_swn_send_unregister_message(struct cifs_swn_reg *swnreg) goto nlmsg_fail; ret = nla_put(skb, CIFS_GENL_ATTR_SWN_IP, sizeof(struct sockaddr_storage), - &swnreg->tcon->ses->server->dstaddr); + &tcon->ses->server->dstaddr); if (ret < 0) goto nlmsg_fail; @@ -242,6 +288,88 @@ nlmsg_fail: } /* + * Allocation-free mirror of extract_hostname() + extract_sharename() from + * fs/smb/client/unc.c. Those helpers kmalloc(GFP_KERNEL); this runs under + * cifs_tcp_ses_lock and tcon->tc_lock, both spinlocks, so we mirror their + * parsing in place against the caller's stable net_name/share_name strings. + * Keep in sync with unc.c. + */ +static bool cifs_swn_tcon_matches(struct cifs_tcon *tcon, + const char *net_name, + const char *share_name) +{ + const char *unc = tcon->tree_name; + const char *host, *share, *delim; + size_t host_len, share_len; + + if (!tcon->use_witness) + return false; + + /* extract_hostname: require strlen(unc) >= 3 */ + if (strnlen(unc, 3) < 3) + return false; + /* extract_hostname: skip all leading '\' characters */ + for (host = unc; *host == '\\'; host++) + ; + if (!*host) + return false; + delim = strchr(host, '\\'); + if (!delim) + return false; + host_len = delim - host; + if (strlen(net_name) != host_len || + strncasecmp(host, net_name, host_len)) + return false; + + /* extract_sharename: start at unc + 2, then first '\' onward */ + share = unc + 2; + delim = strchr(share, '\\'); + if (!delim) + return false; + share = delim + 1; + share_len = strlen(share); + + return strlen(share_name) == share_len && + !strncasecmp(share, share_name, share_len); +} + +/* + * One SWN registration id represents one net/share name pair. Multiple + * mounted tcons can therefore share the id. Pick a live representative at + * use time instead of caching the first tcon pointer in the registration. + */ +static struct cifs_tcon *cifs_swn_get_tcon(struct cifs_swn_reg_info *swnreg) +{ + struct TCP_Server_Info *server; + struct cifs_ses *ses; + struct cifs_tcon *tcon; + + spin_lock(&cifs_tcp_ses_lock); + list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) { + list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) { + list_for_each_entry(tcon, &ses->tcon_list, tcon_list) { + spin_lock(&tcon->tc_lock); + if (tcon->status == TID_EXITING || + !cifs_swn_tcon_matches(tcon, swnreg->net_name, + swnreg->share_name)) { + spin_unlock(&tcon->tc_lock); + continue; + } + ++tcon->tc_count; + trace_smb3_tcon_ref(tcon->debug_id, + tcon->tc_count, + netfs_trace_tcon_ref_get_swn_notify); + spin_unlock(&tcon->tc_lock); + spin_unlock(&cifs_tcp_ses_lock); + return tcon; + } + } + } + spin_unlock(&cifs_tcp_ses_lock); + return NULL; +} + +/* * Try to find a matching registration for the tcon's server name and share name. * Calls to this function must be protected by cifs_swnreg_idr_mutex. * TODO Try to avoid memory allocations @@ -347,8 +475,6 @@ static struct cifs_swn_reg *cifs_get_swn_reg(struct cifs_tcon *tcon) reg->net_name_notify = true; reg->share_name_notify = true; reg->ip_notify = (tcon->capabilities & SMB2_SHARE_CAP_SCALEOUT); - - reg->tcon = tcon; unlock: mutex_unlock(&cifs_swnreg_idr_mutex); @@ -368,11 +494,6 @@ fail_unlock: static void cifs_swn_reg_release(struct kref *ref) { struct cifs_swn_reg *swnreg = container_of(ref, struct cifs_swn_reg, ref_count); - int ret; - - ret = cifs_swn_send_unregister_message(swnreg); - if (ret < 0) - cifs_dbg(VFS, "%s: Failed to send unregister message: %d\n", __func__, ret); idr_remove(&cifs_swnreg_idr, swnreg->id); kfree(swnreg->net_name); @@ -380,23 +501,33 @@ static void cifs_swn_reg_release(struct kref *ref) kfree(swnreg); } -static void cifs_put_swn_reg(struct cifs_swn_reg *swnreg) +static void cifs_put_swn_reg_locked(struct cifs_swn_reg *swnreg, + struct cifs_tcon *tcon) { - mutex_lock(&cifs_swnreg_idr_mutex); + if (kref_read(&swnreg->ref_count) == 1) { + struct cifs_swn_reg_info swnreg_info; + int ret; + + cifs_swn_snapshot_reg(swnreg, &swnreg_info); + ret = cifs_swn_send_unregister_message(&swnreg_info, tcon); + if (ret < 0) + cifs_dbg(VFS, "%s: Failed to send unregister message: %d\n", + __func__, ret); + } + kref_put(&swnreg->ref_count, cifs_swn_reg_release); - mutex_unlock(&cifs_swnreg_idr_mutex); } -static int cifs_swn_resource_state_changed(struct cifs_swn_reg *swnreg, const char *name, int state) +static int cifs_swn_resource_state_changed(struct cifs_tcon *tcon, const char *name, int state) { switch (state) { case CIFS_SWN_RESOURCE_STATE_UNAVAILABLE: cifs_dbg(FYI, "%s: resource name '%s' become unavailable\n", __func__, name); - cifs_signal_cifsd_for_reconnect(swnreg->tcon->ses->server, true); + cifs_signal_cifsd_for_reconnect(tcon->ses->server, true); break; case CIFS_SWN_RESOURCE_STATE_AVAILABLE: cifs_dbg(FYI, "%s: resource name '%s' become available\n", __func__, name); - cifs_signal_cifsd_for_reconnect(swnreg->tcon->ses->server, true); + cifs_signal_cifsd_for_reconnect(tcon->ses->server, true); break; case CIFS_SWN_RESOURCE_STATE_UNKNOWN: cifs_dbg(FYI, "%s: resource name '%s' changed to unknown state\n", __func__, name); @@ -502,7 +633,7 @@ unlock: return ret; } -static int cifs_swn_client_move(struct cifs_swn_reg *swnreg, struct sockaddr_storage *addr) +static int cifs_swn_client_move(struct cifs_tcon *tcon, struct sockaddr_storage *addr) { struct sockaddr_in *ipv4 = (struct sockaddr_in *)addr; struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)addr; @@ -512,14 +643,17 @@ static int cifs_swn_client_move(struct cifs_swn_reg *swnreg, struct sockaddr_sto else if (addr->ss_family == AF_INET6) cifs_dbg(FYI, "%s: move to %pI6\n", __func__, &ipv6->sin6_addr); - return cifs_swn_reconnect(swnreg->tcon, addr); + return cifs_swn_reconnect(tcon, addr); } int cifs_swn_notify(struct sk_buff *skb, struct genl_info *info) { struct cifs_swn_reg *swnreg; + struct cifs_swn_reg_info swnreg_info; + struct cifs_tcon *tcon; char name[256]; int type; + int ret = 0; if (info->attrs[CIFS_GENL_ATTR_SWN_REGISTRATION_ID]) { int swnreg_id; @@ -527,21 +661,34 @@ int cifs_swn_notify(struct sk_buff *skb, struct genl_info *info) swnreg_id = nla_get_u32(info->attrs[CIFS_GENL_ATTR_SWN_REGISTRATION_ID]); mutex_lock(&cifs_swnreg_idr_mutex); swnreg = idr_find(&cifs_swnreg_idr, swnreg_id); - mutex_unlock(&cifs_swnreg_idr_mutex); if (swnreg == NULL) { + mutex_unlock(&cifs_swnreg_idr_mutex); cifs_dbg(FYI, "%s: registration id %d not found\n", __func__, swnreg_id); return -EINVAL; } + ret = cifs_swn_dup_reg(swnreg, &swnreg_info); + mutex_unlock(&cifs_swnreg_idr_mutex); + if (ret) + return ret; } else { cifs_dbg(FYI, "%s: missing registration id attribute\n", __func__); return -EINVAL; } + tcon = cifs_swn_get_tcon(&swnreg_info); + if (!tcon) { + cifs_dbg(FYI, "%s: registration id %d has no live tcon\n", + __func__, swnreg_info.id); + ret = -ENODEV; + goto free_info; + } + if (info->attrs[CIFS_GENL_ATTR_SWN_NOTIFICATION_TYPE]) { type = nla_get_u32(info->attrs[CIFS_GENL_ATTR_SWN_NOTIFICATION_TYPE]); } else { cifs_dbg(FYI, "%s: missing notification type attribute\n", __func__); - return -EINVAL; + ret = -EINVAL; + goto out; } switch (type) { @@ -553,15 +700,18 @@ int cifs_swn_notify(struct sk_buff *skb, struct genl_info *info) sizeof(name)); } else { cifs_dbg(FYI, "%s: missing resource name attribute\n", __func__); - return -EINVAL; + ret = -EINVAL; + goto out; } if (info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_STATE]) { state = nla_get_u32(info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_STATE]); } else { cifs_dbg(FYI, "%s: missing resource state attribute\n", __func__); - return -EINVAL; + ret = -EINVAL; + goto out; } - return cifs_swn_resource_state_changed(swnreg, name, state); + ret = cifs_swn_resource_state_changed(tcon, name, state); + break; } case CIFS_SWN_NOTIFICATION_CLIENT_MOVE: { struct sockaddr_storage addr; @@ -570,28 +720,36 @@ int cifs_swn_notify(struct sk_buff *skb, struct genl_info *info) nla_memcpy(&addr, info->attrs[CIFS_GENL_ATTR_SWN_IP], sizeof(addr)); } else { cifs_dbg(FYI, "%s: missing IP address attribute\n", __func__); - return -EINVAL; + ret = -EINVAL; + goto out; } - return cifs_swn_client_move(swnreg, &addr); + ret = cifs_swn_client_move(tcon, &addr); + break; } default: cifs_dbg(FYI, "%s: unknown notification type %d\n", __func__, type); break; } - return 0; +out: + cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_swn_notify); +free_info: + cifs_swn_free_reg_info(&swnreg_info); + return ret; } int cifs_swn_register(struct cifs_tcon *tcon) { struct cifs_swn_reg *swnreg; + struct cifs_swn_reg_info swnreg_info; int ret; swnreg = cifs_get_swn_reg(tcon); if (IS_ERR(swnreg)) return PTR_ERR(swnreg); - ret = cifs_swn_send_register_message(swnreg); + cifs_swn_snapshot_reg(swnreg, &swnreg_info); + ret = cifs_swn_send_register_message(&swnreg_info, tcon); if (ret < 0) { cifs_dbg(VFS, "%s: Failed to send swn register message: %d\n", __func__, ret); /* Do not put the swnreg or return error, the echo task will retry */ @@ -612,35 +770,68 @@ int cifs_swn_unregister(struct cifs_tcon *tcon) return PTR_ERR(swnreg); } + cifs_put_swn_reg_locked(swnreg, tcon); mutex_unlock(&cifs_swnreg_idr_mutex); - cifs_put_swn_reg(swnreg); - return 0; } -void cifs_swn_dump(struct seq_file *m) +/* + * Snapshot one registration under cifs_swnreg_idr_mutex and return. Callers + * intentionally do the per-registration network/genlmsg work without the + * mutex held, both to keep the critical section short and to avoid nesting + * cifs_swnreg_idr_mutex inside the higher tc_lock when a live tcon is then + * pinned for the send. + */ +static int cifs_swn_get_next_reg_info(int *id, struct cifs_swn_reg_info *info) { struct cifs_swn_reg *swnreg; + int ret = 0; + + mutex_lock(&cifs_swnreg_idr_mutex); + swnreg = idr_get_next(&cifs_swnreg_idr, id); + if (swnreg) { + ret = cifs_swn_dup_reg(swnreg, info); + if (!ret) { + *id = swnreg->id + 1; + ret = 1; + } + } + mutex_unlock(&cifs_swnreg_idr_mutex); + + return ret; +} + +void cifs_swn_dump(struct seq_file *m) +{ + struct cifs_swn_reg_info swnreg_info; + struct cifs_tcon *tcon; struct sockaddr_in *sa; struct sockaddr_in6 *sa6; - int id; + int id = 0; + int ret; seq_puts(m, "Witness registrations:"); - mutex_lock(&cifs_swnreg_idr_mutex); - idr_for_each_entry(&cifs_swnreg_idr, swnreg, id) { + while ((ret = cifs_swn_get_next_reg_info(&id, &swnreg_info)) > 0) { seq_printf(m, "\nId: %u Refs: %u Network name: '%s'%s Share name: '%s'%s Ip address: ", - id, kref_read(&swnreg->ref_count), - swnreg->net_name, swnreg->net_name_notify ? "(y)" : "(n)", - swnreg->share_name, swnreg->share_name_notify ? "(y)" : "(n)"); - switch (swnreg->tcon->ses->server->dstaddr.ss_family) { + swnreg_info.id, swnreg_info.ref_count, + swnreg_info.net_name, swnreg_info.net_name_notify ? "(y)" : "(n)", + swnreg_info.share_name, swnreg_info.share_name_notify ? "(y)" : "(n)"); + + tcon = cifs_swn_get_tcon(&swnreg_info); + if (!tcon) { + seq_puts(m, "(no live tcon)"); + goto next; + } + + switch (tcon->ses->server->dstaddr.ss_family) { case AF_INET: - sa = (struct sockaddr_in *) &swnreg->tcon->ses->server->dstaddr; + sa = (struct sockaddr_in *)&tcon->ses->server->dstaddr; seq_printf(m, "%pI4", &sa->sin_addr.s_addr); break; case AF_INET6: - sa6 = (struct sockaddr_in6 *) &swnreg->tcon->ses->server->dstaddr; + sa6 = (struct sockaddr_in6 *)&tcon->ses->server->dstaddr; seq_printf(m, "%pI6", &sa6->sin6_addr.s6_addr); if (sa6->sin6_scope_id) seq_printf(m, "%%%u", sa6->sin6_scope_id); @@ -648,23 +839,38 @@ void cifs_swn_dump(struct seq_file *m) default: seq_puts(m, "(unknown)"); } - seq_printf(m, "%s", swnreg->ip_notify ? "(y)" : "(n)"); + cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_swn_notify); +next: + seq_printf(m, "%s", swnreg_info.ip_notify ? "(y)" : "(n)"); + cifs_swn_free_reg_info(&swnreg_info); } - mutex_unlock(&cifs_swnreg_idr_mutex); + if (ret < 0) + seq_printf(m, "\nFailed to snapshot witness registration: %d", ret); seq_puts(m, "\n"); } void cifs_swn_check(void) { - struct cifs_swn_reg *swnreg; - int id; + struct cifs_swn_reg_info swnreg_info; + struct cifs_tcon *tcon; + int id = 0; int ret; - mutex_lock(&cifs_swnreg_idr_mutex); - idr_for_each_entry(&cifs_swnreg_idr, swnreg, id) { - ret = cifs_swn_send_register_message(swnreg); + while ((ret = cifs_swn_get_next_reg_info(&id, &swnreg_info)) > 0) { + tcon = cifs_swn_get_tcon(&swnreg_info); + if (!tcon) { + cifs_dbg(FYI, "%s: registration id %d has no live tcon\n", + __func__, swnreg_info.id); + goto free_info; + } + + ret = cifs_swn_send_register_message(&swnreg_info, tcon); if (ret < 0) cifs_dbg(FYI, "%s: Failed to send register message: %d\n", __func__, ret); + cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_swn_notify); +free_info: + cifs_swn_free_reg_info(&swnreg_info); } - mutex_unlock(&cifs_swnreg_idr_mutex); + if (ret < 0) + cifs_dbg(FYI, "%s: Failed to snapshot registration: %d\n", __func__, ret); } diff --git a/fs/smb/client/trace.h b/fs/smb/client/trace.h index b99ec5a417fa..5b21ad3c15fb 100644 --- a/fs/smb/client/trace.h +++ b/fs/smb/client/trace.h @@ -181,6 +181,7 @@ EM(netfs_trace_tcon_ref_get_find, "GET Find ") \ EM(netfs_trace_tcon_ref_get_find_sess_tcon, "GET FndSes") \ EM(netfs_trace_tcon_ref_get_reconnect_server, "GET Reconn") \ + EM(netfs_trace_tcon_ref_get_swn_notify, "GET SwnNot") \ EM(netfs_trace_tcon_ref_new, "NEW ") \ EM(netfs_trace_tcon_ref_new_ipc, "NEW Ipc ") \ EM(netfs_trace_tcon_ref_new_reconnect_server, "NEW Reconn") \ @@ -192,6 +193,7 @@ EM(netfs_trace_tcon_ref_put_mnt_ctx, "PUT MntCtx") \ EM(netfs_trace_tcon_ref_put_dfs_refer, "PUT DfsRfr") \ EM(netfs_trace_tcon_ref_put_reconnect_server, "PUT Reconn") \ + EM(netfs_trace_tcon_ref_put_swn_notify, "PUT SwnNot") \ EM(netfs_trace_tcon_ref_put_tlink, "PUT Tlink ") \ EM(netfs_trace_tcon_ref_see_cancelled_close, "SEE Cn-Cls") \ EM(netfs_trace_tcon_ref_see_fscache_collision, "SEE FV-CO!") \ |