dm-log-writes fixes from Mike
diff --git a/drivers/md/dm-log-writes.c b/drivers/md/dm-log-writes.c
index 4aa627a..3c84777 100644
--- a/drivers/md/dm-log-writes.c
+++ b/drivers/md/dm-log-writes.c
@@ -137,7 +137,7 @@
if (err) {
unsigned long flags;
- DMERR("Error writing log block %d\n", err);
+ DMERR("Error writing log block %d", err);
spin_lock_irqsave(&lc->blocks_lock, flags);
lc->logging_enabled = false;
spin_unlock_irqrestore(&lc->blocks_lock, flags);
@@ -335,8 +335,7 @@
spin_lock_irq(&lc->blocks_lock);
if (!list_empty(&lc->logging_blocks)) {
block = list_first_entry(&lc->logging_blocks,
- struct pending_block,
- list);
+ struct pending_block, list);
list_del_init(&block->list);
if (!lc->logging_enabled)
goto next;
@@ -362,8 +361,7 @@
lc->logged_entries++;
atomic_inc(&lc->io_blocks);
- super = (block->flags &
- (LOG_FUA_FLAG | LOG_MARK_FLAG));
+ super = (block->flags & (LOG_FUA_FLAG | LOG_MARK_FLAG));
if (super)
atomic_inc(&lc->io_blocks);
}
@@ -380,9 +378,8 @@
lc->logging_enabled = false;
spin_unlock_irq(&lc->blocks_lock);
}
- } else {
+ } else
free_pending_block(lc, block);
- }
continue;
}
@@ -429,15 +426,13 @@
atomic_set(&lc->pending_blocks, 0);
devname = dm_shift_arg(&as);
- if (dm_get_device(ti, devname, dm_table_get_mode(ti->table),
- &lc->dev)) {
+ if (dm_get_device(ti, devname, dm_table_get_mode(ti->table), &lc->dev)) {
ti->error = "Device lookup failed";
goto bad;
}
logdevname = dm_shift_arg(&as);
- if (dm_get_device(ti, logdevname, dm_table_get_mode(ti->table),
- &lc->logdev)) {
+ if (dm_get_device(ti, logdevname, dm_table_get_mode(ti->table), &lc->logdev)) {
ti->error = "Log device lookup failed";
dm_put_device(ti, lc->dev);
goto bad;
@@ -477,13 +472,13 @@
block = kzalloc(sizeof(struct pending_block), GFP_KERNEL);
if (!block) {
- DMERR("Error allocating pending block\n");
+ DMERR("Error allocating pending block");
return -ENOMEM;
}
block->data = kstrndup(data, maxsize, GFP_KERNEL);
if (!block->data) {
- DMERR("Error copying mark data\n");
+ DMERR("Error copying mark data");
kfree(block);
return -ENOMEM;
}
@@ -527,9 +522,10 @@
struct log_writes_c *lc = ti->private;
bio->bi_bdev = lc->dev->bdev;
+ // FIXME: why would bi_sector ever need to be changed?
+ // if you just copied dm-linear then it is misplaced since there isn't an offset
if (bio_sectors(bio))
- bio->bi_iter.bi_sector =
- dm_target_offset(ti, bio->bi_iter.bi_sector);
+ bio->bi_iter.bi_sector = dm_target_offset(ti, bio->bi_iter.bi_sector);
}
static int log_writes_map(struct dm_target *ti, struct bio *bio)
@@ -568,8 +564,8 @@
if (discard_bio)
alloc_size = sizeof(struct pending_block);
else
- alloc_size = sizeof(struct pending_block) +
- sizeof(struct bio_vec) * bio_segments(bio);
+ alloc_size = sizeof(struct pending_block) + sizeof(struct bio_vec) * bio_segments(bio);
+
block = kzalloc(alloc_size, GFP_NOIO);
if (!block) {
DMERR("Error allocating pending block");
@@ -614,6 +610,9 @@
* the actual contents into new pages so we know the data will always be
* there.
*/
+ // FIXME: why not just hold onto the original bio until "way later"?
+ // would doing so compromise the target's function?
+ // seems it'd avoid all this duplication (of state and data) in pending_block
bio_for_each_segment(bv, bio, iter) {
struct page *page;
void *src, *dst;
@@ -661,16 +660,14 @@
spin_lock_irqsave(&lc->blocks_lock, flags);
if (block->flags & LOG_FLUSH_FLAG) {
- list_splice_tail_init(&block->list,
- &lc->logging_blocks);
+ list_splice_tail_init(&block->list, &lc->logging_blocks);
list_add_tail(&block->list, &lc->logging_blocks);
wake_up_process(lc->log_kthread);
} else if (block->flags & LOG_FUA_FLAG) {
list_add_tail(&block->list, &lc->logging_blocks);
wake_up_process(lc->log_kthread);
- } else {
+ } else
list_add_tail(&block->list, &lc->unflushed_blocks);
- }
spin_unlock_irqrestore(&lc->blocks_lock, flags);
}
@@ -692,11 +689,11 @@
DMEMIT("%llu %llu", lc->logged_entries,
(unsigned long long)lc->next_sector - 1);
if (!lc->logging_enabled)
- DMEMIT(" logging disabled");
+ DMEMIT(" logging_disabled");
break;
case STATUSTYPE_TABLE:
- DMEMIT("%s %s ", lc->dev->name, lc->logdev->name);
+ DMEMIT("%s %s", lc->dev->name, lc->logdev->name);
break;
}
}
@@ -742,57 +739,37 @@
}
/*
- * Valid messages
- *
- * mark <mark data> - specify the marked data.
+ * Messages supported:
+ * mark <mark data> - specify the marked data.
*/
static int log_writes_message(struct dm_target *ti, unsigned argc, char **argv)
{
+ int r = -EINVAL;
struct log_writes_c *lc = ti->private;
if (argc != 2) {
- DMWARN("Invalid log-writes message arguments, expect 2 "
- "argument, got %d", argc);
- return -EINVAL;
+ DMWARN("Invalid log-writes message arguments, expect 2 arguments, got %d", argc);
+ return r;
}
- if (!strcasecmp(argv[0], "mark")) {
- int ret;
+ if (!strcasecmp(argv[0], "mark"))
+ r = log_mark(lc, argv[1]);
+ else
+ DMWARN("Unrecognised log writes target message received: %s", argv[0]);
- ret = log_mark(lc, argv[1]);
- if (ret)
- return ret;
- } else {
- DMWARN("Invalid argument %s", argv[0]);
- return -EINVAL;
- }
-
- return 0;
+ return r;
}
-static void log_writes_io_hints(struct dm_target *ti,
- struct queue_limits *limits)
+static void log_writes_io_hints(struct dm_target *ti, struct queue_limits *limits)
{
struct log_writes_c *lc = ti->private;
struct request_queue *q = bdev_get_queue(lc->dev->bdev);
- sector_t max_discard = (UINT_MAX >> SECTOR_SHIFT);
- if (!q || !blk_queue_discard(q))
+ if (!q || !blk_queue_discard(q)) {
lc->device_supports_discard = false;
-
- if (lc->device_supports_discard) {
- struct queue_limits *data_limits = &q->limits;
- limits->max_discard_sectors =
- min_t(unsigned int, data_limits->max_discard_sectors,
- max_discard);
- limits->discard_granularity =
- max_t(unsigned int, data_limits->discard_granularity,
- 1 << SECTOR_SHIFT);
- } else {
limits->discard_granularity = 1 << SECTOR_SHIFT;
- limits->max_discard_sectors = max_discard;
+ limits->max_discard_sectors = (UINT_MAX >> SECTOR_SHIFT);
}
- dump_stack();
}
static struct target_type log_writes_target = {
@@ -830,6 +807,6 @@
module_init(dm_log_writes_init);
module_exit(dm_log_writes_exit);
-MODULE_DESCRIPTION(DM_NAME " write log target");
+MODULE_DESCRIPTION(DM_NAME " log writes target");
MODULE_AUTHOR("Josef Bacik <jbacik@fb.com>");
MODULE_LICENSE("GPL");
