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Diffstat (limited to 'drivers/md/bcache/super.c')
-rw-r--r--drivers/md/bcache/super.c227
1 files changed, 183 insertions, 44 deletions
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 1b63ac876169..26e374fbf57c 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -40,6 +40,7 @@ static const char invalid_uuid[] = {
static struct kobject *bcache_kobj;
struct mutex bch_register_lock;
+bool bcache_is_reboot;
LIST_HEAD(bch_cache_sets);
static LIST_HEAD(uncached_devices);
@@ -49,6 +50,7 @@ static wait_queue_head_t unregister_wait;
struct workqueue_struct *bcache_wq;
struct workqueue_struct *bch_journal_wq;
+
#define BTREE_MAX_PAGES (256 * 1024 / PAGE_SIZE)
/* limitation of partitions number on single bcache device */
#define BCACHE_MINORS 128
@@ -197,7 +199,9 @@ err:
static void write_bdev_super_endio(struct bio *bio)
{
struct cached_dev *dc = bio->bi_private;
- /* XXX: error checking */
+
+ if (bio->bi_status)
+ bch_count_backing_io_errors(dc, bio);
closure_put(&dc->sb_write);
}
@@ -691,6 +695,7 @@ static void bcache_device_link(struct bcache_device *d, struct cache_set *c,
{
unsigned int i;
struct cache *ca;
+ int ret;
for_each_cache(ca, d->c, i)
bd_link_disk_holder(ca->bdev, d->disk);
@@ -698,9 +703,13 @@ static void bcache_device_link(struct bcache_device *d, struct cache_set *c,
snprintf(d->name, BCACHEDEVNAME_SIZE,
"%s%u", name, d->id);
- WARN(sysfs_create_link(&d->kobj, &c->kobj, "cache") ||
- sysfs_create_link(&c->kobj, &d->kobj, d->name),
- "Couldn't create device <-> cache set symlinks");
+ ret = sysfs_create_link(&d->kobj, &c->kobj, "cache");
+ if (ret < 0)
+ pr_err("Couldn't create device -> cache set symlink");
+
+ ret = sysfs_create_link(&c->kobj, &d->kobj, d->name);
+ if (ret < 0)
+ pr_err("Couldn't create cache set -> device symlink");
clear_bit(BCACHE_DEV_UNLINK_DONE, &d->flags);
}
@@ -908,7 +917,7 @@ static int cached_dev_status_update(void *arg)
}
-void bch_cached_dev_run(struct cached_dev *dc)
+int bch_cached_dev_run(struct cached_dev *dc)
{
struct bcache_device *d = &dc->disk;
char *buf = kmemdup_nul(dc->sb.label, SB_LABEL_SIZE, GFP_KERNEL);
@@ -919,11 +928,19 @@ void bch_cached_dev_run(struct cached_dev *dc)
NULL,
};
+ if (dc->io_disable) {
+ pr_err("I/O disabled on cached dev %s",
+ dc->backing_dev_name);
+ return -EIO;
+ }
+
if (atomic_xchg(&dc->running, 1)) {
kfree(env[1]);
kfree(env[2]);
kfree(buf);
- return;
+ pr_info("cached dev %s is running already",
+ dc->backing_dev_name);
+ return -EBUSY;
}
if (!d->c &&
@@ -949,8 +966,11 @@ void bch_cached_dev_run(struct cached_dev *dc)
kfree(buf);
if (sysfs_create_link(&d->kobj, &disk_to_dev(d->disk)->kobj, "dev") ||
- sysfs_create_link(&disk_to_dev(d->disk)->kobj, &d->kobj, "bcache"))
- pr_debug("error creating sysfs link");
+ sysfs_create_link(&disk_to_dev(d->disk)->kobj,
+ &d->kobj, "bcache")) {
+ pr_err("Couldn't create bcache dev <-> disk sysfs symlinks");
+ return -ENOMEM;
+ }
dc->status_update_thread = kthread_run(cached_dev_status_update,
dc, "bcache_status_update");
@@ -959,6 +979,8 @@ void bch_cached_dev_run(struct cached_dev *dc)
"continue to run without monitoring backing "
"device status");
}
+
+ return 0;
}
/*
@@ -996,7 +1018,6 @@ static void cached_dev_detach_finish(struct work_struct *w)
BUG_ON(!test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags));
BUG_ON(refcount_read(&dc->count));
- mutex_lock(&bch_register_lock);
if (test_and_clear_bit(BCACHE_DEV_WB_RUNNING, &dc->disk.flags))
cancel_writeback_rate_update_dwork(dc);
@@ -1012,6 +1033,8 @@ static void cached_dev_detach_finish(struct work_struct *w)
bch_write_bdev_super(dc, &cl);
closure_sync(&cl);
+ mutex_lock(&bch_register_lock);
+
calc_cached_dev_sectors(dc->disk.c);
bcache_device_detach(&dc->disk);
list_move(&dc->list, &uncached_devices);
@@ -1054,6 +1077,7 @@ int bch_cached_dev_attach(struct cached_dev *dc, struct cache_set *c,
uint32_t rtime = cpu_to_le32((u32)ktime_get_real_seconds());
struct uuid_entry *u;
struct cached_dev *exist_dc, *t;
+ int ret = 0;
if ((set_uuid && memcmp(set_uuid, c->sb.set_uuid, 16)) ||
(!set_uuid && memcmp(dc->sb.set_uuid, c->sb.set_uuid, 16)))
@@ -1153,6 +1177,8 @@ int bch_cached_dev_attach(struct cached_dev *dc, struct cache_set *c,
down_write(&dc->writeback_lock);
if (bch_cached_dev_writeback_start(dc)) {
up_write(&dc->writeback_lock);
+ pr_err("Couldn't start writeback facilities for %s",
+ dc->disk.disk->disk_name);
return -ENOMEM;
}
@@ -1163,7 +1189,22 @@ int bch_cached_dev_attach(struct cached_dev *dc, struct cache_set *c,
bch_sectors_dirty_init(&dc->disk);
- bch_cached_dev_run(dc);
+ ret = bch_cached_dev_run(dc);
+ if (ret && (ret != -EBUSY)) {
+ up_write(&dc->writeback_lock);
+ /*
+ * bch_register_lock is held, bcache_device_stop() is not
+ * able to be directly called. The kthread and kworker
+ * created previously in bch_cached_dev_writeback_start()
+ * have to be stopped manually here.
+ */
+ kthread_stop(dc->writeback_thread);
+ cancel_writeback_rate_update_dwork(dc);
+ pr_err("Couldn't run cached device %s",
+ dc->backing_dev_name);
+ return ret;
+ }
+
bcache_device_link(&dc->disk, c, "bdev");
atomic_inc(&c->attached_dev_nr);
@@ -1190,18 +1231,16 @@ static void cached_dev_free(struct closure *cl)
{
struct cached_dev *dc = container_of(cl, struct cached_dev, disk.cl);
- mutex_lock(&bch_register_lock);
-
if (test_and_clear_bit(BCACHE_DEV_WB_RUNNING, &dc->disk.flags))
cancel_writeback_rate_update_dwork(dc);
if (!IS_ERR_OR_NULL(dc->writeback_thread))
kthread_stop(dc->writeback_thread);
- if (dc->writeback_write_wq)
- destroy_workqueue(dc->writeback_write_wq);
if (!IS_ERR_OR_NULL(dc->status_update_thread))
kthread_stop(dc->status_update_thread);
+ mutex_lock(&bch_register_lock);
+
if (atomic_read(&dc->running))
bd_unlink_disk_holder(dc->bdev, dc->disk.disk);
bcache_device_free(&dc->disk);
@@ -1290,6 +1329,7 @@ static int register_bdev(struct cache_sb *sb, struct page *sb_page,
{
const char *err = "cannot allocate memory";
struct cache_set *c;
+ int ret = -ENOMEM;
bdevname(bdev, dc->backing_dev_name);
memcpy(&dc->sb, sb, sizeof(struct cache_sb));
@@ -1319,14 +1359,18 @@ static int register_bdev(struct cache_sb *sb, struct page *sb_page,
bch_cached_dev_attach(dc, c, NULL);
if (BDEV_STATE(&dc->sb) == BDEV_STATE_NONE ||
- BDEV_STATE(&dc->sb) == BDEV_STATE_STALE)
- bch_cached_dev_run(dc);
+ BDEV_STATE(&dc->sb) == BDEV_STATE_STALE) {
+ err = "failed to run cached device";
+ ret = bch_cached_dev_run(dc);
+ if (ret)
+ goto err;
+ }
return 0;
err:
pr_notice("error %s: %s", dc->backing_dev_name, err);
bcache_device_stop(&dc->disk);
- return -EIO;
+ return ret;
}
/* Flash only volumes */
@@ -1437,8 +1481,6 @@ int bch_flash_dev_create(struct cache_set *c, uint64_t size)
bool bch_cached_dev_error(struct cached_dev *dc)
{
- struct cache_set *c;
-
if (!dc || test_bit(BCACHE_DEV_CLOSING, &dc->disk.flags))
return false;
@@ -1449,21 +1491,6 @@ bool bch_cached_dev_error(struct cached_dev *dc)
pr_err("stop %s: too many IO errors on backing device %s\n",
dc->disk.disk->disk_name, dc->backing_dev_name);
- /*
- * If the cached device is still attached to a cache set,
- * even dc->io_disable is true and no more I/O requests
- * accepted, cache device internal I/O (writeback scan or
- * garbage collection) may still prevent bcache device from
- * being stopped. So here CACHE_SET_IO_DISABLE should be
- * set to c->flags too, to make the internal I/O to cache
- * device rejected and stopped immediately.
- * If c is NULL, that means the bcache device is not attached
- * to any cache set, then no CACHE_SET_IO_DISABLE bit to set.
- */
- c = dc->disk.c;
- if (c && test_and_set_bit(CACHE_SET_IO_DISABLE, &c->flags))
- pr_info("CACHE_SET_IO_DISABLE already set");
-
bcache_device_stop(&dc->disk);
return true;
}
@@ -1564,19 +1591,23 @@ static void cache_set_flush(struct closure *cl)
kobject_put(&c->internal);
kobject_del(&c->kobj);
- if (c->gc_thread)
+ if (!IS_ERR_OR_NULL(c->gc_thread))
kthread_stop(c->gc_thread);
if (!IS_ERR_OR_NULL(c->root))
list_add(&c->root->list, &c->btree_cache);
- /* Should skip this if we're unregistering because of an error */
- list_for_each_entry(b, &c->btree_cache, list) {
- mutex_lock(&b->write_lock);
- if (btree_node_dirty(b))
- __bch_btree_node_write(b, NULL);
- mutex_unlock(&b->write_lock);
- }
+ /*
+ * Avoid flushing cached nodes if cache set is retiring
+ * due to too many I/O errors detected.
+ */
+ if (!test_bit(CACHE_SET_IO_DISABLE, &c->flags))
+ list_for_each_entry(b, &c->btree_cache, list) {
+ mutex_lock(&b->write_lock);
+ if (btree_node_dirty(b))
+ __bch_btree_node_write(b, NULL);
+ mutex_unlock(&b->write_lock);
+ }
for_each_cache(ca, c, i)
if (ca->alloc_thread)
@@ -1849,6 +1880,23 @@ static int run_cache_set(struct cache_set *c)
if (bch_btree_check(c))
goto err;
+ /*
+ * bch_btree_check() may occupy too much system memory which
+ * has negative effects to user space application (e.g. data
+ * base) performance. Shrink the mca cache memory proactively
+ * here to avoid competing memory with user space workloads..
+ */
+ if (!c->shrinker_disabled) {
+ struct shrink_control sc;
+
+ sc.gfp_mask = GFP_KERNEL;
+ sc.nr_to_scan = c->btree_cache_used * c->btree_pages;
+ /* first run to clear b->accessed tag */
+ c->shrink.scan_objects(&c->shrink, &sc);
+ /* second run to reap non-accessed nodes */
+ c->shrink.scan_objects(&c->shrink, &sc);
+ }
+
bch_journal_mark(c, &journal);
bch_initial_gc_finish(c);
pr_debug("btree_check() done");
@@ -1957,7 +2005,7 @@ err:
}
closure_sync(&cl);
- /* XXX: test this, it's broken */
+
bch_cache_set_error(c, "%s", err);
return -EIO;
@@ -2251,9 +2299,13 @@ err:
static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
const char *buffer, size_t size);
+static ssize_t bch_pending_bdevs_cleanup(struct kobject *k,
+ struct kobj_attribute *attr,
+ const char *buffer, size_t size);
kobj_attribute_write(register, register_bcache);
kobj_attribute_write(register_quiet, register_bcache);
+kobj_attribute_write(pendings_cleanup, bch_pending_bdevs_cleanup);
static bool bch_is_open_backing(struct block_device *bdev)
{
@@ -2301,6 +2353,11 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
if (!try_module_get(THIS_MODULE))
return -EBUSY;
+ /* For latest state of bcache_is_reboot */
+ smp_mb();
+ if (bcache_is_reboot)
+ return -EBUSY;
+
path = kstrndup(buffer, size, GFP_KERNEL);
if (!path)
goto err;
@@ -2378,8 +2435,61 @@ err:
goto out;
}
+
+struct pdev {
+ struct list_head list;
+ struct cached_dev *dc;
+};
+
+static ssize_t bch_pending_bdevs_cleanup(struct kobject *k,
+ struct kobj_attribute *attr,
+ const char *buffer,
+ size_t size)
+{
+ LIST_HEAD(pending_devs);
+ ssize_t ret = size;
+ struct cached_dev *dc, *tdc;
+ struct pdev *pdev, *tpdev;
+ struct cache_set *c, *tc;
+
+ mutex_lock(&bch_register_lock);
+ list_for_each_entry_safe(dc, tdc, &uncached_devices, list) {
+ pdev = kmalloc(sizeof(struct pdev), GFP_KERNEL);
+ if (!pdev)
+ break;
+ pdev->dc = dc;
+ list_add(&pdev->list, &pending_devs);
+ }
+
+ list_for_each_entry_safe(pdev, tpdev, &pending_devs, list) {
+ list_for_each_entry_safe(c, tc, &bch_cache_sets, list) {
+ char *pdev_set_uuid = pdev->dc->sb.set_uuid;
+ char *set_uuid = c->sb.uuid;
+
+ if (!memcmp(pdev_set_uuid, set_uuid, 16)) {
+ list_del(&pdev->list);
+ kfree(pdev);
+ break;
+ }
+ }
+ }
+ mutex_unlock(&bch_register_lock);
+
+ list_for_each_entry_safe(pdev, tpdev, &pending_devs, list) {
+ pr_info("delete pdev %p", pdev);
+ list_del(&pdev->list);
+ bcache_device_stop(&pdev->dc->disk);
+ kfree(pdev);
+ }
+
+ return ret;
+}
+
static int bcache_reboot(struct notifier_block *n, unsigned long code, void *x)
{
+ if (bcache_is_reboot)
+ return NOTIFY_DONE;
+
if (code == SYS_DOWN ||
code == SYS_HALT ||
code == SYS_POWER_OFF) {
@@ -2392,19 +2502,45 @@ static int bcache_reboot(struct notifier_block *n, unsigned long code, void *x)
mutex_lock(&bch_register_lock);
+ if (bcache_is_reboot)
+ goto out;
+
+ /* New registration is rejected since now */
+ bcache_is_reboot = true;
+ /*
+ * Make registering caller (if there is) on other CPU
+ * core know bcache_is_reboot set to true earlier
+ */
+ smp_mb();
+
if (list_empty(&bch_cache_sets) &&
list_empty(&uncached_devices))
goto out;
+ mutex_unlock(&bch_register_lock);
+
pr_info("Stopping all devices:");
+ /*
+ * The reason bch_register_lock is not held to call
+ * bch_cache_set_stop() and bcache_device_stop() is to
+ * avoid potential deadlock during reboot, because cache
+ * set or bcache device stopping process will acqurie
+ * bch_register_lock too.
+ *
+ * We are safe here because bcache_is_reboot sets to
+ * true already, register_bcache() will reject new
+ * registration now. bcache_is_reboot also makes sure
+ * bcache_reboot() won't be re-entered on by other thread,
+ * so there is no race in following list iteration by
+ * list_for_each_entry_safe().
+ */
list_for_each_entry_safe(c, tc, &bch_cache_sets, list)
bch_cache_set_stop(c);
list_for_each_entry_safe(dc, tdc, &uncached_devices, list)
bcache_device_stop(&dc->disk);
- mutex_unlock(&bch_register_lock);
/*
* Give an early chance for other kthreads and
@@ -2496,6 +2632,7 @@ static int __init bcache_init(void)
static const struct attribute *files[] = {
&ksysfs_register.attr,
&ksysfs_register_quiet.attr,
+ &ksysfs_pendings_cleanup.attr,
NULL
};
@@ -2531,6 +2668,8 @@ static int __init bcache_init(void)
bch_debug_init();
closure_debug_init();
+ bcache_is_reboot = false;
+
return 0;
err:
bcache_exit();