The filesystem gains the USERSPACE_STACK incomat bit and the
s_cluster_info field on the superblock. When a userspace stack is in
use, the name of the stack is stored on-disk for mount-time
verification.
The "cluster_stack" option is added to mount(2) processing. The mount
process needs to pass the matching stack name. If the passed name and
the on-disk name do not match, the mount is failed.
When using the classic o2cb stack, the incompat bit is *not* set and no
mount option is used other than the usual heartbeat=local. Thus, the
filesystem is compatible with older tools.
Signed-off-by: Joel Becker <joel.becker@xxxxxxxxxx>
---
fs/ocfs2/ocfs2.h | 7 ++++
fs/ocfs2/ocfs2_fs.h | 40 +++++++++++++++++++++-
fs/ocfs2/super.c | 90 ++++++++++++++++++++++++++++++++++++++++++++++++++-
3 files changed, 134 insertions(+), 3 deletions(-)
diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index af929ec..9ff5811 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -248,6 +248,7 @@ struct ocfs2_super
struct ocfs2_alloc_stats alloc_stats;
char dev_str[20]; /* "major,minor" of the device */
+ char osb_cluster_stack[OCFS2_STACK_LABEL_LEN + 1];
struct ocfs2_cluster_connection *cconn;
struct ocfs2_lock_res osb_super_lockres;
struct ocfs2_lock_res osb_rename_lockres;
@@ -368,6 +369,12 @@ static inline int ocfs2_is_soft_readonly(struct ocfs2_super *osb)
return ret;
}
+static inline int ocfs2_userspace_stack(struct ocfs2_super *osb)
+{
+ return (osb->s_feature_incompat &
+ OCFS2_FEATURE_INCOMPAT_USERSPACE_STACK);
+}
+
static inline int ocfs2_mount_local(struct ocfs2_super *osb)
{
return (osb->s_feature_incompat & OCFS2_FEATURE_INCOMPAT_LOCAL_MOUNT);
diff --git a/fs/ocfs2/ocfs2_fs.h b/fs/ocfs2/ocfs2_fs.h
index c495023..52c4266 100644
--- a/fs/ocfs2/ocfs2_fs.h
+++ b/fs/ocfs2/ocfs2_fs.h
@@ -89,7 +89,8 @@
#define OCFS2_FEATURE_INCOMPAT_SUPP (OCFS2_FEATURE_INCOMPAT_LOCAL_MOUNT \
| OCFS2_FEATURE_INCOMPAT_SPARSE_ALLOC \
| OCFS2_FEATURE_INCOMPAT_INLINE_DATA \
- | OCFS2_FEATURE_INCOMPAT_EXTENDED_SLOT_MAP)
+ | OCFS2_FEATURE_INCOMPAT_EXTENDED_SLOT_MAP \
+ | OCFS2_FEATURE_INCOMPAT_USERSPACE_STACK)
#define OCFS2_FEATURE_RO_COMPAT_SUPP OCFS2_FEATURE_RO_COMPAT_UNWRITTEN
/*
@@ -131,6 +132,17 @@
/*
+ * Support for alternate, userspace cluster stacks. If set, the superblock
+ * field s_cluster_info contains a tag for the alternate stack in use as
+ * well as the name of the cluster being joined.
+ * mount.ocfs2 must pass in a matching stack name.
+ *
+ * If not set, the classic stack will be used. This is compatbile with
+ * all older versions.
+ */
+#define OCFS2_FEATURE_INCOMPAT_USERSPACE_STACK 0x0080
+
+/*
* backup superblock flag is used to indicate that this volume
* has backup superblocks.
*/
@@ -272,6 +284,10 @@ struct ocfs2_new_group_input {
#define OCFS2_VOL_UUID_LEN 16
#define OCFS2_MAX_VOL_LABEL_LEN 64
+/* The alternate, userspace stack fields */
+#define OCFS2_STACK_LABEL_LEN 4
+#define OCFS2_CLUSTER_NAME_LEN 16
+
/* Journal limits (in bytes) */
#define OCFS2_MIN_JOURNAL_SIZE (4 * 1024 * 1024)
@@ -513,6 +529,13 @@ struct ocfs2_slot_map_extended {
*/
};
+struct ocfs2_cluster_info {
+/*00*/ __u8 ci_stack[OCFS2_STACK_LABEL_LEN];
+ __le32 ci_reserved;
+/*08*/ __u8 ci_cluster[OCFS2_CLUSTER_NAME_LEN];
+/*18*/
+};
+
/*
* On disk superblock for OCFS2
* Note that it is contained inside an ocfs2_dinode, so all offsets
@@ -545,7 +568,20 @@ struct ocfs2_super_block {
* group header */
/*50*/ __u8 s_label[OCFS2_MAX_VOL_LABEL_LEN]; /* Label for mounting, etc. */
/*90*/ __u8 s_uuid[OCFS2_VOL_UUID_LEN]; /* 128-bit uuid */
-/*A0*/
+/*A0*/ struct ocfs2_cluster_info s_cluster_info; /* Selected userspace
+ stack. Only valid
+ with INCOMPAT flag. */
+/*B8*/ __le64 s_reserved2[17]; /* Fill out superblock */
+/*140*/
+
+ /*
+ * NOTE: As stated above, all offsets are relative to
+ * ocfs2_dinode.id2, which is at 0xC0 in the inode.
+ * 0xC0 + 0x140 = 0x200 or 512 bytes. A superblock must fit within
+ * our smallest blocksize, which is 512 bytes. To ensure this,
+ * we reserve the space in s_reserved2. Anything past s_reserved2
+ * will not be available on the smallest blocksize.
+ */
};
/*
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index e27a0d4..96ebe36 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -87,6 +87,7 @@ struct mount_options
unsigned int atime_quantum;
signed short slot;
unsigned int localalloc_opt;
+ char cluster_stack[OCFS2_STACK_LABEL_LEN + 1];
};
static int ocfs2_parse_options(struct super_block *sb, char *options,
@@ -152,6 +153,7 @@ enum {
Opt_commit,
Opt_localalloc,
Opt_localflocks,
+ Opt_stack,
Opt_err,
};
@@ -170,6 +172,7 @@ static match_table_t tokens = {
{Opt_commit, "commit=%u"},
{Opt_localalloc, "localalloc=%d"},
{Opt_localflocks, "localflocks"},
+ {Opt_stack, "cluster_stack=%s"},
{Opt_err, NULL}
};
@@ -549,8 +552,17 @@ static int ocfs2_verify_heartbeat(struct ocfs2_super *osb)
}
}
+ if (ocfs2_userspace_stack(osb)) {
+ if (osb->s_mount_opt & OCFS2_MOUNT_HB_LOCAL) {
+ mlog(ML_ERROR, "Userspace stack expected, but "
+ "o2cb heartbeat arguments passed to mount\n");
+ return -EINVAL;
+ }
+ }
+
if (!(osb->s_mount_opt & OCFS2_MOUNT_HB_LOCAL)) {
- if (!ocfs2_mount_local(osb) && !ocfs2_is_hard_readonly(osb)) {
+ if (!ocfs2_mount_local(osb) && !ocfs2_is_hard_readonly(osb) &&
+ !ocfs2_userspace_stack(osb)) {
mlog(ML_ERROR, "Heartbeat has to be started to mount "
"a read-write clustered device.\n");
return -EINVAL;
@@ -560,6 +572,35 @@ static int ocfs2_verify_heartbeat(struct ocfs2_super *osb)
return 0;
}
+/*
+ * If we're using a userspace stack, mount should have passed
+ * a name that matches the disk. If not, mount should not
+ * have passed a stack.
+ */
+static int ocfs2_verify_userspace_stack(struct ocfs2_super *osb,
+ struct mount_options *mopt)
+{
+ if (!ocfs2_userspace_stack(osb) && mopt->cluster_stack[0]) {
+ mlog(ML_ERROR,
+ "cluster stack passed to mount, but this filesystem "
+ "does not support it\n");
+ return -EINVAL;
+ }
+
+ if (ocfs2_userspace_stack(osb) &&
+ strncmp(osb->osb_cluster_stack, mopt->cluster_stack,
+ OCFS2_STACK_LABEL_LEN)) {
+ mlog(ML_ERROR,
+ "cluster stack passed to mount (\"%s\") does not "
+ "match the filesystem (\"%s\")\n",
+ mopt->cluster_stack,
+ osb->osb_cluster_stack);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
static int ocfs2_fill_super(struct super_block *sb, void *data, int silent)
{
struct dentry *root;
@@ -598,6 +639,10 @@ static int ocfs2_fill_super(struct super_block *sb, void *data, int silent)
osb->osb_commit_interval = parsed_options.commit_interval;
osb->local_alloc_size = parsed_options.localalloc_opt;
+ status = ocfs2_verify_userspace_stack(osb, &parsed_options);
+ if (status)
+ goto read_super_error;
+
sb->s_magic = OCFS2_SUPER_MAGIC;
/* Hard readonly mode only if: bdev_read_only, MS_RDONLY,
@@ -752,6 +797,7 @@ static int ocfs2_parse_options(struct super_block *sb,
mopt->atime_quantum = OCFS2_DEFAULT_ATIME_QUANTUM;
mopt->slot = OCFS2_INVALID_SLOT;
mopt->localalloc_opt = OCFS2_DEFAULT_LOCAL_ALLOC_SIZE;
+ mopt->cluster_stack[0] = '\0';
if (!options) {
status = 1;
@@ -853,6 +899,25 @@ static int ocfs2_parse_options(struct super_block *sb,
if (!is_remount)
mopt->mount_opt |= OCFS2_MOUNT_LOCALFLOCKS;
break;
+ case Opt_stack:
+ /* Check both that the option we were passed
+ * is of the right length and that it is a proper
+ * string of the right length.
+ */
+ if (((args[0].to - args[0].from) !=
+ OCFS2_STACK_LABEL_LEN) ||
+ (strnlen(args[0].from,
+ OCFS2_STACK_LABEL_LEN) !=
+ OCFS2_STACK_LABEL_LEN)) {
+ mlog(ML_ERROR,
+ "Invalid cluster_stack option\n");
+ status = 0;
+ goto bail;
+ }
+ memcpy(mopt->cluster_stack, args[0].from,
+ OCFS2_STACK_LABEL_LEN);
+ mopt->cluster_stack[OCFS2_STACK_LABEL_LEN] = '\0';
+ break;
default:
mlog(ML_ERROR,
"Unrecognized mount option \"%s\" "
@@ -911,6 +976,10 @@ static int ocfs2_show_options(struct seq_file *s, struct vfsmount *mnt)
if (opts & OCFS2_MOUNT_LOCALFLOCKS)
seq_printf(s, ",localflocks,");
+ if (osb->osb_cluster_stack[0])
+ seq_printf(s, ",cluster_stack=%.*s", OCFS2_STACK_LABEL_LEN,
+ osb->osb_cluster_stack);
+
return 0;
}
@@ -1403,6 +1472,25 @@ static int ocfs2_initialize_super(struct super_block *sb,
goto bail;
}
+ if (ocfs2_userspace_stack(osb)) {
+ memcpy(osb->osb_cluster_stack,
+ OCFS2_RAW_SB(di)->s_cluster_info.ci_stack,
+ OCFS2_STACK_LABEL_LEN);
+ osb->osb_cluster_stack[OCFS2_STACK_LABEL_LEN] = '\0';
+ if (strlen(osb->osb_cluster_stack) != OCFS2_STACK_LABEL_LEN) {
+ mlog(ML_ERROR,
+ "couldn't mount because of an invalid "
+ "cluster stack label (%s) \n",
+ osb->osb_cluster_stack);
+ status = -EINVAL;
+ goto bail;
+ }
+ } else {
+ /* The empty string is identical with classic tools that
+ * don't know about s_cluster_info. */
+ osb->osb_cluster_stack[0] = '\0';
+ }
+
get_random_bytes(&osb->s_next_generation, sizeof(u32));
/* FIXME
--
1.5.3.8
--
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