bcache: Add on error panic/unregister setting

Works kind of like the ext4 setting, to panic or remount read only on
errors.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>

diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index bf37474a6888ce4af9b14a09d0da784159a49b97..578615604be583d231addd0987e59b13b3b9113d 100644 (file)
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -843,8 +843,14 @@ struct cache_set {
        atomic_long_t           cache_read_races;
        atomic_long_t           writeback_keys_done;
        atomic_long_t           writeback_keys_failed;
+
+       enum                    {
+               ON_ERROR_UNREGISTER,
+               ON_ERROR_PANIC,
+       }                       on_error;
        unsigned                error_limit;
        unsigned                error_decay;
+
        unsigned short          journal_delay_ms;
        unsigned                verify:1;
        unsigned                key_merging_disabled:1;

diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c
index 8435f81e5d858012e8aca6be8204e923a34b1d01..15d34597c001fea7ab748569a99f34215d000db1 100644 (file)
--- a/drivers/md/bcache/journal.c
+++ b/drivers/md/bcache/journal.c
@@ -305,10 +305,9 @@ int bch_journal_replay(struct cache_set *s, struct list_head *list,
        list_for_each_entry(i, list, list) {
                BUG_ON(i->pin && atomic_read(i->pin) != 1);
 
-               if (n != i->j.seq)
-                       pr_err(
-               "journal entries %llu-%llu missing! (replaying %llu-%llu)\n",
-               n, i->j.seq - 1, start, end);
+               cache_set_err_on(n != i->j.seq, s,
+"bcache: journal entries %llu-%llu missing! (replaying %llu-%llu)",
+                                n, i->j.seq - 1, start, end);
 
                for (k = i->j.start;
                     k < end(&i->j);

diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index fd37342a7eb53aa242f2194014775703df8f3562..74f2e902d8768ab84650d998b6ce7e4e5a34f800 100644 (file)
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1260,7 +1260,8 @@ bool bch_cache_set_error(struct cache_set *c, const char *fmt, ...)
 {
        va_list args;
 
-       if (test_bit(CACHE_SET_STOPPING, &c->flags))
+       if (c->on_error != ON_ERROR_PANIC &&
+           test_bit(CACHE_SET_STOPPING, &c->flags))
                return false;
 
        /* XXX: we can be called from atomic context
@@ -1275,6 +1276,9 @@ bool bch_cache_set_error(struct cache_set *c, const char *fmt, ...)
 
        printk(", disabling caching\n");
 
+       if (c->on_error == ON_ERROR_PANIC)
+               panic("panic forced after error\n");
+
        bch_cache_set_unregister(c);
        return true;
 }

diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index a87fbb5a093f250cb8f6a30d32efbfdaa16f9b3f..adb9f3c2704e8a0e1c0056538236b38655deaa54 100644 (file)
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -21,6 +21,12 @@ static const char * const cache_replacement_policies[] = {
        NULL
 };
 
+static const char * const error_actions[] = {
+       "unregister",
+       "panic",
+       NULL
+};
+
 write_attribute(attach);
 write_attribute(detach);
 write_attribute(unregister);
@@ -90,6 +96,7 @@ rw_attribute(discard);
 rw_attribute(running);
 rw_attribute(label);
 rw_attribute(readahead);
+rw_attribute(errors);
 rw_attribute(io_error_limit);
 rw_attribute(io_error_halflife);
 rw_attribute(verify);
@@ -492,6 +499,10 @@ lock_root:
        sysfs_print(writeback_keys_failed,
                    atomic_long_read(&c->writeback_keys_failed));
 
+       if (attr == &sysfs_errors)
+               return bch_snprint_string_list(buf, PAGE_SIZE, error_actions,
+                                              c->on_error);
+
        /* See count_io_errors for why 88 */
        sysfs_print(io_error_halflife,  c->error_decay * 88);
        sysfs_print(io_error_limit,     c->error_limit >> IO_ERROR_SHIFT);
@@ -569,6 +580,15 @@ STORE(__bch_cache_set)
        sysfs_strtoul(congested_write_threshold_us,
                      c->congested_write_threshold_us);
 
+       if (attr == &sysfs_errors) {
+               ssize_t v = bch_read_string_list(buf, error_actions);
+
+               if (v < 0)
+                       return v;
+
+               c->on_error = v;
+       }
+
        if (attr == &sysfs_io_error_limit)
                c->error_limit = strtoul_or_return(buf) << IO_ERROR_SHIFT;
 
@@ -620,6 +640,7 @@ static struct attribute *bch_cache_set_files[] = {
        &sysfs_average_key_size,
        &sysfs_dirty_data,
 
+       &sysfs_errors,
        &sysfs_io_error_limit,
        &sysfs_io_error_halflife,
        &sysfs_congested,