ocfs2: Add "preferred slot" mount option
ocfs2 will attempt to assign the node the slot# provided in the mount
option. Failure to assign the preferred slot is not an error. This small
feature can be useful for automated testing.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index a860633..648ef8e 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -219,6 +219,7 @@
u16 max_slots;
s16 node_num;
s16 slot_num;
+ s16 preferred_slot;
int s_sectsize_bits;
int s_clustersize;
int s_clustersize_bits;
diff --git a/fs/ocfs2/slot_map.c b/fs/ocfs2/slot_map.c
index d8b7906..af4882b 100644
--- a/fs/ocfs2/slot_map.c
+++ b/fs/ocfs2/slot_map.c
@@ -121,17 +121,25 @@
return ret;
}
-static s16 __ocfs2_find_empty_slot(struct ocfs2_slot_info *si)
+static s16 __ocfs2_find_empty_slot(struct ocfs2_slot_info *si, s16 preferred)
{
int i;
s16 ret = OCFS2_INVALID_SLOT;
+ if (preferred >= 0 && preferred < si->si_num_slots) {
+ if (OCFS2_INVALID_SLOT == si->si_global_node_nums[preferred]) {
+ ret = preferred;
+ goto out;
+ }
+ }
+
for(i = 0; i < si->si_num_slots; i++) {
if (OCFS2_INVALID_SLOT == si->si_global_node_nums[i]) {
ret = (s16) i;
break;
}
}
+out:
return ret;
}
@@ -248,7 +256,7 @@
if (slot == OCFS2_INVALID_SLOT) {
/* if no slot yet, then just take 1st available
* one. */
- slot = __ocfs2_find_empty_slot(si);
+ slot = __ocfs2_find_empty_slot(si, osb->preferred_slot);
if (slot == OCFS2_INVALID_SLOT) {
spin_unlock(&si->si_lock);
mlog(ML_ERROR, "no free slots available!\n");
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 86b559c..f07718a 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -82,7 +82,8 @@
MODULE_LICENSE("GPL");
static int ocfs2_parse_options(struct super_block *sb, char *options,
- unsigned long *mount_opt, int is_remount);
+ unsigned long *mount_opt, s16 *slot,
+ int is_remount);
static void ocfs2_put_super(struct super_block *sb);
static int ocfs2_mount_volume(struct super_block *sb);
static int ocfs2_remount(struct super_block *sb, int *flags, char *data);
@@ -140,6 +141,7 @@
Opt_data_ordered,
Opt_data_writeback,
Opt_atime_quantum,
+ Opt_slot,
Opt_err,
};
@@ -154,6 +156,7 @@
{Opt_data_ordered, "data=ordered"},
{Opt_data_writeback, "data=writeback"},
{Opt_atime_quantum, "atime_quantum=%u"},
+ {Opt_slot, "preferred_slot=%u"},
{Opt_err, NULL}
};
@@ -355,9 +358,10 @@
int incompat_features;
int ret = 0;
unsigned long parsed_options;
+ s16 slot;
struct ocfs2_super *osb = OCFS2_SB(sb);
- if (!ocfs2_parse_options(sb, data, &parsed_options, 1)) {
+ if (!ocfs2_parse_options(sb, data, &parsed_options, &slot, 1)) {
ret = -EINVAL;
goto out;
}
@@ -534,6 +538,7 @@
struct dentry *root;
int status, sector_size;
unsigned long parsed_opt;
+ s16 slot;
struct inode *inode = NULL;
struct ocfs2_super *osb = NULL;
struct buffer_head *bh = NULL;
@@ -541,7 +546,7 @@
mlog_entry("%p, %p, %i", sb, data, silent);
- if (!ocfs2_parse_options(sb, data, &parsed_opt, 0)) {
+ if (!ocfs2_parse_options(sb, data, &parsed_opt, &slot, 0)) {
status = -EINVAL;
goto read_super_error;
}
@@ -571,6 +576,7 @@
brelse(bh);
bh = NULL;
osb->s_mount_opt = parsed_opt;
+ osb->preferred_slot = slot;
sb->s_magic = OCFS2_SUPER_MAGIC;
@@ -713,6 +719,7 @@
static int ocfs2_parse_options(struct super_block *sb,
char *options,
unsigned long *mount_opt,
+ s16 *slot,
int is_remount)
{
int status;
@@ -722,6 +729,7 @@
options ? options : "(none)");
*mount_opt = 0;
+ *slot = OCFS2_INVALID_SLOT;
if (!options) {
status = 1;
@@ -782,6 +790,15 @@
else
osb->s_atime_quantum = OCFS2_DEFAULT_ATIME_QUANTUM;
break;
+ case Opt_slot:
+ option = 0;
+ if (match_int(&args[0], &option)) {
+ status = 0;
+ goto bail;
+ }
+ if (option)
+ *slot = (s16)option;
+ break;
default:
mlog(ML_ERROR,
"Unrecognized mount option \"%s\" "