Updated to support new mount API (rebased on Ronnie's patch series).
Let me know if you see any problems.
On Mon, Nov 30, 2020 at 12:04 PM Samuel Cabrero <scabrero@xxxxxxx> wrote:
>
> Add 'witness' mount option to register for witness notifications.
>
> Signed-off-by: Samuel Cabrero <scabrero@xxxxxxx>
> ---
> fs/cifs/cifsfs.c | 5 +++++
> fs/cifs/cifsglob.h | 4 ++++
> fs/cifs/connect.c | 35 ++++++++++++++++++++++++++++++++++-
> 3 files changed, 43 insertions(+), 1 deletion(-)
>
> diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
> index 8111d0109a2e..c2bbc444b463 100644
> --- a/fs/cifs/cifsfs.c
> +++ b/fs/cifs/cifsfs.c
> @@ -637,6 +637,11 @@ cifs_show_options(struct seq_file *s, struct dentry *root)
> seq_printf(s, ",multichannel,max_channels=%zu",
> tcon->ses->chan_max);
>
> +#ifdef CONFIG_CIFS_SWN_UPCALL
> + if (tcon->use_witness)
> + seq_puts(s, ",witness");
> +#endif
> +
> return 0;
> }
>
> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
> index 484ec2d8c5c9..f45b7c0fbceb 100644
> --- a/fs/cifs/cifsglob.h
> +++ b/fs/cifs/cifsglob.h
> @@ -619,6 +619,7 @@ struct smb_vol {
> unsigned int max_channels;
> __u16 compression; /* compression algorithm 0xFFFF default 0=disabled */
> bool rootfs:1; /* if it's a SMB root file system */
> + bool witness:1; /* use witness protocol */
> };
>
> /**
> @@ -1177,6 +1178,9 @@ struct cifs_tcon {
> int remap:2;
> struct list_head ulist; /* cache update list */
> #endif
> +#ifdef CONFIG_CIFS_SWN_UPCALL
> + bool use_witness:1; /* use witness protocol */
> +#endif
> };
>
> /*
> diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
> index a938371af6ef..22d46c8acc7f 100644
> --- a/fs/cifs/connect.c
> +++ b/fs/cifs/connect.c
> @@ -102,7 +102,7 @@ enum {
> Opt_resilient, Opt_noresilient,
> Opt_domainauto, Opt_rdma, Opt_modesid, Opt_rootfs,
> Opt_multichannel, Opt_nomultichannel,
> - Opt_compress,
> + Opt_compress, Opt_witness,
>
> /* Mount options which take numeric value */
> Opt_backupuid, Opt_backupgid, Opt_uid,
> @@ -276,6 +276,7 @@ static const match_table_t cifs_mount_option_tokens = {
> { Opt_ignore, "relatime" },
> { Opt_ignore, "_netdev" },
> { Opt_rootfs, "rootfs" },
> + { Opt_witness, "witness" },
>
> { Opt_err, NULL }
> };
> @@ -1540,6 +1541,13 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
> vol->rootfs = true;
> #endif
> break;
> + case Opt_witness:
> +#ifndef CONFIG_CIFS_SWN_UPCALL
> + cifs_dbg(VFS, "Witness support needs CONFIG_CIFS_SWN_UPCALL kernel config option set\n");
> + goto cifs_parse_mount_err;
> +#endif
> + vol->witness = true;
> + break;
> case Opt_posixpaths:
> vol->posix_paths = 1;
> break;
> @@ -3160,6 +3168,8 @@ cifs_put_tcon(struct cifs_tcon *tcon)
> return;
> }
>
> + /* TODO witness unregister */
> +
> list_del_init(&tcon->tcon_list);
> spin_unlock(&cifs_tcp_ses_lock);
>
> @@ -3321,6 +3331,26 @@ cifs_get_tcon(struct cifs_ses *ses, struct smb_vol *volume_info)
> tcon->use_resilient = true;
> }
>
> +#ifdef CONFIG_CIFS_SWN_UPCALL
> + tcon->use_witness = false;
> + if (volume_info->witness) {
> + if (ses->server->vals->protocol_id >= SMB30_PROT_ID) {
> + if (tcon->capabilities & SMB2_SHARE_CAP_CLUSTER) {
> + /* TODO witness register */
> + tcon->use_witness = true;
> + } else {
> + cifs_dbg(VFS, "witness requested on mount but no CLUSTER capability on share\n");
> + rc = -EOPNOTSUPP;
> + goto out_fail;
> + }
> + } else {
> + cifs_dbg(VFS, "SMB3 or later required for witness option\n");
> + rc = -EOPNOTSUPP;
> + goto out_fail;
> + }
> + }
> +#endif
> +
> /* If the user really knows what they are doing they can override */
> if (tcon->share_flags & SMB2_SHAREFLAG_NO_CACHING) {
> if (volume_info->cache_ro)
> @@ -5072,6 +5102,9 @@ cifs_construct_tcon(struct cifs_sb_info *cifs_sb, kuid_t fsuid)
> vol_info->sectype = master_tcon->ses->sectype;
> vol_info->sign = master_tcon->ses->sign;
> vol_info->seal = master_tcon->seal;
> +#ifdef CONFIG_CIFS_SWN_UPCALL
> + vol_info->witness = master_tcon->use_witness;
> +#endif
>
> rc = cifs_set_vol_auth(vol_info, master_tcon->ses);
> if (rc) {
> --
> 2.29.2
>
--
Thanks,
Steve
From 11de8d5dc0521d7e6782fac8605bb7646d66d7e3 Mon Sep 17 00:00:00 2001
From: Samuel Cabrero <scabrero@xxxxxxx>
Date: Fri, 11 Dec 2020 22:59:29 -0600
Subject: [PATCH] cifs: add witness mount option and data structs
Add 'witness' mount option to register for witness notifications.
Signed-off-by: Samuel Cabrero <scabrero@xxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
---
fs/cifs/cifsfs.c | 5 +++++
fs/cifs/cifsglob.h | 3 +++
fs/cifs/connect.c | 25 +++++++++++++++++++++++++
fs/cifs/fs_context.c | 8 ++++++++
fs/cifs/fs_context.h | 2 ++
5 files changed, 43 insertions(+)
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 5d32561ae2ed..f810b25dfeb8 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -638,6 +638,11 @@ cifs_show_options(struct seq_file *s, struct dentry *root)
seq_printf(s, ",multichannel,max_channels=%zu",
tcon->ses->chan_max);
+#ifdef CONFIG_CIFS_SWN_UPCALL
+ if (tcon->use_witness)
+ seq_puts(s, ",witness");
+#endif
+
return 0;
}
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index b46809260e79..78438102f091 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -1086,6 +1086,9 @@ struct cifs_tcon {
int remap:2;
struct list_head ulist; /* cache update list */
#endif
+#ifdef CONFIG_CIFS_SWN_UPCALL
+ bool use_witness:1; /* use witness protocol */
+#endif
};
/*
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index ec80b6c3e20f..46d4f5469688 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -1944,6 +1944,8 @@ cifs_put_tcon(struct cifs_tcon *tcon)
return;
}
+ /* TODO witness unregister */
+
list_del_init(&tcon->tcon_list);
spin_unlock(&cifs_tcp_ses_lock);
@@ -2104,6 +2106,26 @@ cifs_get_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
}
tcon->use_resilient = true;
}
+#ifdef CONFIG_CIFS_SWN_UPCALL
+ tcon->use_witness = false;
+ if (ctx->witness) {
+ if (ses->server->vals->protocol_id >= SMB30_PROT_ID) {
+ if (tcon->capabilities & SMB2_SHARE_CAP_CLUSTER) {
+ /* TODO witness register */
+ tcon->use_witness = true;
+ } else {
+ /* TODO: try to extend for non-cluster uses (eg multichannel) */
+ cifs_dbg(VFS, "witness requested on mount but no CLUSTER capability on share\n");
+ rc = -EOPNOTSUPP;
+ goto out_fail;
+ }
+ } else {
+ cifs_dbg(VFS, "SMB3 or later required for witness option\n");
+ rc = -EOPNOTSUPP;
+ goto out_fail;
+ }
+ }
+#endif
/* If the user really knows what they are doing they can override */
if (tcon->share_flags & SMB2_SHAREFLAG_NO_CACHING) {
@@ -3856,6 +3878,9 @@ cifs_construct_tcon(struct cifs_sb_info *cifs_sb, kuid_t fsuid)
ctx->sectype = master_tcon->ses->sectype;
ctx->sign = master_tcon->ses->sign;
ctx->seal = master_tcon->seal;
+#ifdef CONFIG_CIFS_SWN_UPCALL
+ ctx->witness = master_tcon->use_witness;
+#endif
rc = cifs_set_vol_auth(ctx, master_tcon->ses);
if (rc) {
diff --git a/fs/cifs/fs_context.c b/fs/cifs/fs_context.c
index 9120d148c5f1..fe5cc60f4393 100644
--- a/fs/cifs/fs_context.c
+++ b/fs/cifs/fs_context.c
@@ -119,6 +119,7 @@ const struct fs_parameter_spec smb3_fs_parameters[] = {
fsparam_flag("modesid", Opt_modesid),
fsparam_flag("rootfs", Opt_rootfs),
fsparam_flag("compress", Opt_compress),
+ fsparam_flag("witness", Opt_witness),
/* Mount options which take numeric value */
fsparam_u32("backupuid", Opt_backupuid),
@@ -1004,6 +1005,13 @@ static int smb3_fs_context_parse_param(struct fs_context *fc,
if (cifs_parse_cache_flavor(param->string, ctx) != 0)
goto cifs_parse_mount_err;
break;
+ case Opt_witness:
+#ifndef CONFIG_CIFS_SWN_UPCALL
+ cifs_dbg(VFS, "Witness support needs CONFIG_CIFS_SWN_UPCALL config option\n");
+ goto cifs_parse_mount_err;
+#endif
+ ctx->witness = true;
+ break;
case Opt_rootfs:
#ifdef CONFIG_CIFS_ROOT
ctx->rootfs = true;
diff --git a/fs/cifs/fs_context.h b/fs/cifs/fs_context.h
index d4a905a80883..aaec8a819d34 100644
--- a/fs/cifs/fs_context.h
+++ b/fs/cifs/fs_context.h
@@ -102,6 +102,7 @@ enum cifs_param {
Opt_rootfs,
Opt_multichannel,
Opt_compress,
+ Opt_witness,
/* Mount options which take numeric value */
Opt_backupuid,
@@ -241,6 +242,7 @@ struct smb3_fs_context {
unsigned int max_channels;
__u16 compression; /* compression algorithm 0xFFFF default 0=disabled */
bool rootfs:1; /* if it's a SMB root file system */
+ bool witness:1; /* use witness protocol */
char *mount_options;
};
--
2.27.0
