diff mbox series

[v4,06/11] cifs: Set witness notification handler for messages from userspace daemon

Message ID 20201130180257.31787-7-scabrero@suse.de (mailing list archive)
State New, archived
Headers show
Series Witness protocol support for transparent failover | expand

Commit Message

Samuel Cabrero Nov. 30, 2020, 6:02 p.m. UTC 
+ Set a handler for the witness notification messages received from the
  userspace daemon.

+ Handle the resource state change notification. When the resource
  becomes unavailable or available set the tcp status to
  CifsNeedReconnect for all channels.

Signed-off-by: Samuel Cabrero <scabrero@suse.de>
---
 fs/cifs/cifs_swn.c                     | 86 ++++++++++++++++++++++++++
 fs/cifs/cifs_swn.h                     |  4 ++
 fs/cifs/netlink.c                      |  9 +++
 include/uapi/linux/cifs/cifs_netlink.h | 17 +++++
 4 files changed, 116 insertions(+)

Comments

Steve French Dec. 12, 2020, 5:55 a.m. UTC | #1 
tentatively merged into cifs-2.6.git for-next    Let me know if any
updates needed to it

On Mon, Nov 30, 2020 at 12:05 PM Samuel Cabrero <scabrero@suse.de> wrote:
>
> + Set a handler for the witness notification messages received from the
>   userspace daemon.
>
> + Handle the resource state change notification. When the resource
>   becomes unavailable or available set the tcp status to
>   CifsNeedReconnect for all channels.
>
> Signed-off-by: Samuel Cabrero <scabrero@suse.de>
> ---
>  fs/cifs/cifs_swn.c                     | 86 ++++++++++++++++++++++++++
>  fs/cifs/cifs_swn.h                     |  4 ++
>  fs/cifs/netlink.c                      |  9 +++
>  include/uapi/linux/cifs/cifs_netlink.h | 17 +++++
>  4 files changed, 116 insertions(+)
>
> diff --git a/fs/cifs/cifs_swn.c b/fs/cifs/cifs_swn.c
> index c0af03955d0c..63b0764af5d5 100644
> --- a/fs/cifs/cifs_swn.c
> +++ b/fs/cifs/cifs_swn.c
> @@ -383,6 +383,92 @@ static void cifs_put_swn_reg(struct cifs_swn_reg *swnreg)
>         mutex_unlock(&cifs_swnreg_idr_mutex);
>  }
>
> +static int cifs_swn_resource_state_changed(struct cifs_swn_reg *swnreg, const char *name, int state)
> +{
> +       int i;
> +
> +       switch (state) {
> +       case CIFS_SWN_RESOURCE_STATE_UNAVAILABLE:
> +               cifs_dbg(FYI, "%s: resource name '%s' become unavailable\n", __func__, name);
> +               for (i = 0; i < swnreg->tcon->ses->chan_count; i++) {
> +                       spin_lock(&GlobalMid_Lock);
> +                       if (swnreg->tcon->ses->chans[i].server->tcpStatus != CifsExiting)
> +                               swnreg->tcon->ses->chans[i].server->tcpStatus = CifsNeedReconnect;
> +                       spin_unlock(&GlobalMid_Lock);
> +               }
> +               break;
> +       case CIFS_SWN_RESOURCE_STATE_AVAILABLE:
> +               cifs_dbg(FYI, "%s: resource name '%s' become available\n", __func__, name);
> +               for (i = 0; i < swnreg->tcon->ses->chan_count; i++) {
> +                       spin_lock(&GlobalMid_Lock);
> +                       if (swnreg->tcon->ses->chans[i].server->tcpStatus != CifsExiting)
> +                               swnreg->tcon->ses->chans[i].server->tcpStatus = CifsNeedReconnect;
> +                       spin_unlock(&GlobalMid_Lock);
> +               }
> +               break;
> +       case CIFS_SWN_RESOURCE_STATE_UNKNOWN:
> +               cifs_dbg(FYI, "%s: resource name '%s' changed to unknown state\n", __func__, name);
> +               break;
> +       }
> +       return 0;
> +}
> +
> +int cifs_swn_notify(struct sk_buff *skb, struct genl_info *info)
> +{
> +       struct cifs_swn_reg *swnreg;
> +       char name[256];
> +       int type;
> +
> +       if (info->attrs[CIFS_GENL_ATTR_SWN_REGISTRATION_ID]) {
> +               int swnreg_id;
> +
> +               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) {
> +                       cifs_dbg(FYI, "%s: registration id %d not found\n", __func__, swnreg_id);
> +                       return -EINVAL;
> +               }
> +       } else {
> +               cifs_dbg(FYI, "%s: missing registration id attribute\n", __func__);
> +               return -EINVAL;
> +       }
> +
> +       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;
> +       }
> +
> +       switch (type) {
> +       case CIFS_SWN_NOTIFICATION_RESOURCE_CHANGE: {
> +               int state;
> +
> +               if (info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_NAME]) {
> +                       nla_strlcpy(name, info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_NAME],
> +                                       sizeof(name));
> +               } else {
> +                       cifs_dbg(FYI, "%s: missing resource name attribute\n", __func__);
> +                       return -EINVAL;
> +               }
> +               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;
> +               }
> +               return cifs_swn_resource_state_changed(swnreg, name, state);
> +       }
> +       default:
> +               cifs_dbg(FYI, "%s: unknown notification type %d\n", __func__, type);
> +               break;
> +       }
> +
> +       return 0;
> +}
> +
>  int cifs_swn_register(struct cifs_tcon *tcon)
>  {
>         struct cifs_swn_reg *swnreg;
> diff --git a/fs/cifs/cifs_swn.h b/fs/cifs/cifs_swn.h
> index 69c7bd1035da..7ef9ecedbd05 100644
> --- a/fs/cifs/cifs_swn.h
> +++ b/fs/cifs/cifs_swn.h
> @@ -9,9 +9,13 @@
>  #define _CIFS_SWN_H
>
>  struct cifs_tcon;
> +struct sk_buff;
> +struct genl_info;
>
>  extern int cifs_swn_register(struct cifs_tcon *tcon);
>
>  extern int cifs_swn_unregister(struct cifs_tcon *tcon);
>
> +extern int cifs_swn_notify(struct sk_buff *skb, struct genl_info *info);
> +
>  #endif /* _CIFS_SWN_H */
> diff --git a/fs/cifs/netlink.c b/fs/cifs/netlink.c
> index 83008a56def5..5aaabe4cc0a7 100644
> --- a/fs/cifs/netlink.c
> +++ b/fs/cifs/netlink.c
> @@ -11,6 +11,7 @@
>  #include "netlink.h"
>  #include "cifsglob.h"
>  #include "cifs_debug.h"
> +#include "cifs_swn.h"
>
>  static const struct nla_policy cifs_genl_policy[CIFS_GENL_ATTR_MAX + 1] = {
>         [CIFS_GENL_ATTR_SWN_REGISTRATION_ID]    = { .type = NLA_U32 },
> @@ -24,9 +25,17 @@ static const struct nla_policy cifs_genl_policy[CIFS_GENL_ATTR_MAX + 1] = {
>         [CIFS_GENL_ATTR_SWN_USER_NAME]          = { .type = NLA_STRING },
>         [CIFS_GENL_ATTR_SWN_PASSWORD]           = { .type = NLA_STRING },
>         [CIFS_GENL_ATTR_SWN_DOMAIN_NAME]        = { .type = NLA_STRING },
> +       [CIFS_GENL_ATTR_SWN_NOTIFICATION_TYPE]  = { .type = NLA_U32 },
> +       [CIFS_GENL_ATTR_SWN_RESOURCE_STATE]     = { .type = NLA_U32 },
> +       [CIFS_GENL_ATTR_SWN_RESOURCE_NAME]      = { .type = NLA_STRING},
>  };
>
>  static struct genl_ops cifs_genl_ops[] = {
> +       {
> +               .cmd = CIFS_GENL_CMD_SWN_NOTIFY,
> +               .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
> +               .doit = cifs_swn_notify,
> +       },
>  };
>
>  static const struct genl_multicast_group cifs_genl_mcgrps[] = {
> diff --git a/include/uapi/linux/cifs/cifs_netlink.h b/include/uapi/linux/cifs/cifs_netlink.h
> index 5662e2774513..da3107582f49 100644
> --- a/include/uapi/linux/cifs/cifs_netlink.h
> +++ b/include/uapi/linux/cifs/cifs_netlink.h
> @@ -31,6 +31,9 @@ enum cifs_genl_attributes {
>         CIFS_GENL_ATTR_SWN_USER_NAME,
>         CIFS_GENL_ATTR_SWN_PASSWORD,
>         CIFS_GENL_ATTR_SWN_DOMAIN_NAME,
> +       CIFS_GENL_ATTR_SWN_NOTIFICATION_TYPE,
> +       CIFS_GENL_ATTR_SWN_RESOURCE_STATE,
> +       CIFS_GENL_ATTR_SWN_RESOURCE_NAME,
>         __CIFS_GENL_ATTR_MAX,
>  };
>  #define CIFS_GENL_ATTR_MAX (__CIFS_GENL_ATTR_MAX - 1)
> @@ -39,8 +42,22 @@ enum cifs_genl_commands {
>         CIFS_GENL_CMD_UNSPEC,
>         CIFS_GENL_CMD_SWN_REGISTER,
>         CIFS_GENL_CMD_SWN_UNREGISTER,
> +       CIFS_GENL_CMD_SWN_NOTIFY,
>         __CIFS_GENL_CMD_MAX
>  };
>  #define CIFS_GENL_CMD_MAX (__CIFS_GENL_CMD_MAX - 1)
>
> +enum cifs_swn_notification_type {
> +       CIFS_SWN_NOTIFICATION_RESOURCE_CHANGE = 0x01,
> +       CIFS_SWN_NOTIFICATION_CLIENT_MOVE        = 0x02,
> +       CIFS_SWN_NOTIFICATION_SHARE_MOVE         = 0x03,
> +       CIFS_SWN_NOTIFICATION_IP_CHANGE  = 0x04,
> +};
> +
> +enum cifs_swn_resource_state {
> +       CIFS_SWN_RESOURCE_STATE_UNKNOWN     = 0x00,
> +       CIFS_SWN_RESOURCE_STATE_AVAILABLE   = 0x01,
> +       CIFS_SWN_RESOURCE_STATE_UNAVAILABLE = 0xFF
> +};
> +
>  #endif /* _UAPILINUX_CIFS_NETLINK_H */
> --
> 2.29.2
>
diff mbox series

Patch

diff --git a/fs/cifs/cifs_swn.c b/fs/cifs/cifs_swn.c
index c0af03955d0c..63b0764af5d5 100644
--- a/fs/cifs/cifs_swn.c
+++ b/fs/cifs/cifs_swn.c
@@ -383,6 +383,92 @@  static void cifs_put_swn_reg(struct cifs_swn_reg *swnreg)
 	mutex_unlock(&cifs_swnreg_idr_mutex);
 }
 
+static int cifs_swn_resource_state_changed(struct cifs_swn_reg *swnreg, const char *name, int state)
+{
+	int i;
+
+	switch (state) {
+	case CIFS_SWN_RESOURCE_STATE_UNAVAILABLE:
+		cifs_dbg(FYI, "%s: resource name '%s' become unavailable\n", __func__, name);
+		for (i = 0; i < swnreg->tcon->ses->chan_count; i++) {
+			spin_lock(&GlobalMid_Lock);
+			if (swnreg->tcon->ses->chans[i].server->tcpStatus != CifsExiting)
+				swnreg->tcon->ses->chans[i].server->tcpStatus = CifsNeedReconnect;
+			spin_unlock(&GlobalMid_Lock);
+		}
+		break;
+	case CIFS_SWN_RESOURCE_STATE_AVAILABLE:
+		cifs_dbg(FYI, "%s: resource name '%s' become available\n", __func__, name);
+		for (i = 0; i < swnreg->tcon->ses->chan_count; i++) {
+			spin_lock(&GlobalMid_Lock);
+			if (swnreg->tcon->ses->chans[i].server->tcpStatus != CifsExiting)
+				swnreg->tcon->ses->chans[i].server->tcpStatus = CifsNeedReconnect;
+			spin_unlock(&GlobalMid_Lock);
+		}
+		break;
+	case CIFS_SWN_RESOURCE_STATE_UNKNOWN:
+		cifs_dbg(FYI, "%s: resource name '%s' changed to unknown state\n", __func__, name);
+		break;
+	}
+	return 0;
+}
+
+int cifs_swn_notify(struct sk_buff *skb, struct genl_info *info)
+{
+	struct cifs_swn_reg *swnreg;
+	char name[256];
+	int type;
+
+	if (info->attrs[CIFS_GENL_ATTR_SWN_REGISTRATION_ID]) {
+		int swnreg_id;
+
+		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) {
+			cifs_dbg(FYI, "%s: registration id %d not found\n", __func__, swnreg_id);
+			return -EINVAL;
+		}
+	} else {
+		cifs_dbg(FYI, "%s: missing registration id attribute\n", __func__);
+		return -EINVAL;
+	}
+
+	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;
+	}
+
+	switch (type) {
+	case CIFS_SWN_NOTIFICATION_RESOURCE_CHANGE: {
+		int state;
+
+		if (info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_NAME]) {
+			nla_strlcpy(name, info->attrs[CIFS_GENL_ATTR_SWN_RESOURCE_NAME],
+					sizeof(name));
+		} else {
+			cifs_dbg(FYI, "%s: missing resource name attribute\n", __func__);
+			return -EINVAL;
+		}
+		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;
+		}
+		return cifs_swn_resource_state_changed(swnreg, name, state);
+	}
+	default:
+		cifs_dbg(FYI, "%s: unknown notification type %d\n", __func__, type);
+		break;
+	}
+
+	return 0;
+}
+
 int cifs_swn_register(struct cifs_tcon *tcon)
 {
 	struct cifs_swn_reg *swnreg;
diff --git a/fs/cifs/cifs_swn.h b/fs/cifs/cifs_swn.h
index 69c7bd1035da..7ef9ecedbd05 100644
--- a/fs/cifs/cifs_swn.h
+++ b/fs/cifs/cifs_swn.h
@@ -9,9 +9,13 @@ 
 #define _CIFS_SWN_H
 
 struct cifs_tcon;
+struct sk_buff;
+struct genl_info;
 
 extern int cifs_swn_register(struct cifs_tcon *tcon);
 
 extern int cifs_swn_unregister(struct cifs_tcon *tcon);
 
+extern int cifs_swn_notify(struct sk_buff *skb, struct genl_info *info);
+
 #endif /* _CIFS_SWN_H */
diff --git a/fs/cifs/netlink.c b/fs/cifs/netlink.c
index 83008a56def5..5aaabe4cc0a7 100644
--- a/fs/cifs/netlink.c
+++ b/fs/cifs/netlink.c
@@ -11,6 +11,7 @@ 
 #include "netlink.h"
 #include "cifsglob.h"
 #include "cifs_debug.h"
+#include "cifs_swn.h"
 
 static const struct nla_policy cifs_genl_policy[CIFS_GENL_ATTR_MAX + 1] = {
 	[CIFS_GENL_ATTR_SWN_REGISTRATION_ID]	= { .type = NLA_U32 },
@@ -24,9 +25,17 @@  static const struct nla_policy cifs_genl_policy[CIFS_GENL_ATTR_MAX + 1] = {
 	[CIFS_GENL_ATTR_SWN_USER_NAME]		= { .type = NLA_STRING },
 	[CIFS_GENL_ATTR_SWN_PASSWORD]		= { .type = NLA_STRING },
 	[CIFS_GENL_ATTR_SWN_DOMAIN_NAME]	= { .type = NLA_STRING },
+	[CIFS_GENL_ATTR_SWN_NOTIFICATION_TYPE]	= { .type = NLA_U32 },
+	[CIFS_GENL_ATTR_SWN_RESOURCE_STATE]	= { .type = NLA_U32 },
+	[CIFS_GENL_ATTR_SWN_RESOURCE_NAME]	= { .type = NLA_STRING},
 };
 
 static struct genl_ops cifs_genl_ops[] = {
+	{
+		.cmd = CIFS_GENL_CMD_SWN_NOTIFY,
+		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
+		.doit = cifs_swn_notify,
+	},
 };
 
 static const struct genl_multicast_group cifs_genl_mcgrps[] = {
diff --git a/include/uapi/linux/cifs/cifs_netlink.h b/include/uapi/linux/cifs/cifs_netlink.h
index 5662e2774513..da3107582f49 100644
--- a/include/uapi/linux/cifs/cifs_netlink.h
+++ b/include/uapi/linux/cifs/cifs_netlink.h
@@ -31,6 +31,9 @@  enum cifs_genl_attributes {
 	CIFS_GENL_ATTR_SWN_USER_NAME,
 	CIFS_GENL_ATTR_SWN_PASSWORD,
 	CIFS_GENL_ATTR_SWN_DOMAIN_NAME,
+	CIFS_GENL_ATTR_SWN_NOTIFICATION_TYPE,
+	CIFS_GENL_ATTR_SWN_RESOURCE_STATE,
+	CIFS_GENL_ATTR_SWN_RESOURCE_NAME,
 	__CIFS_GENL_ATTR_MAX,
 };
 #define CIFS_GENL_ATTR_MAX (__CIFS_GENL_ATTR_MAX - 1)
@@ -39,8 +42,22 @@  enum cifs_genl_commands {
 	CIFS_GENL_CMD_UNSPEC,
 	CIFS_GENL_CMD_SWN_REGISTER,
 	CIFS_GENL_CMD_SWN_UNREGISTER,
+	CIFS_GENL_CMD_SWN_NOTIFY,
 	__CIFS_GENL_CMD_MAX
 };
 #define CIFS_GENL_CMD_MAX (__CIFS_GENL_CMD_MAX - 1)
 
+enum cifs_swn_notification_type {
+	CIFS_SWN_NOTIFICATION_RESOURCE_CHANGE = 0x01,
+	CIFS_SWN_NOTIFICATION_CLIENT_MOVE	 = 0x02,
+	CIFS_SWN_NOTIFICATION_SHARE_MOVE	 = 0x03,
+	CIFS_SWN_NOTIFICATION_IP_CHANGE	 = 0x04,
+};
+
+enum cifs_swn_resource_state {
+	CIFS_SWN_RESOURCE_STATE_UNKNOWN     = 0x00,
+	CIFS_SWN_RESOURCE_STATE_AVAILABLE   = 0x01,
+	CIFS_SWN_RESOURCE_STATE_UNAVAILABLE = 0xFF
+};
+
 #endif /* _UAPILINUX_CIFS_NETLINK_H */