btrfs: factor check and flush helpers from __btrfsic_submit_bio

Split out two helpers to make __btrfsic_submit_bio more readable.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/check-integrity.c b/fs/btrfs/check-integrity.c
index b8f9dfa..89cdf6e 100644 (file)
--- a/fs/btrfs/check-integrity.c
+++ b/fs/btrfs/check-integrity.c
@@ -2633,6 +2633,73 @@ static struct btrfsic_dev_state *btrfsic_dev_state_lookup(dev_t dev)
                                                  &btrfsic_dev_state_hashtable);
 }
 
+static void btrfsic_check_write_bio(struct bio *bio, struct btrfsic_dev_state *dev_state)
+{
+       unsigned int segs = bio_segments(bio);
+       u64 dev_bytenr = 512 * bio->bi_iter.bi_sector;
+       u64 cur_bytenr = dev_bytenr;
+       struct bvec_iter iter;
+       struct bio_vec bvec;
+       char **mapped_datav;
+       int bio_is_patched = 0;
+       int i = 0;
+
+       if (dev_state->state->print_mask & BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
+               pr_info(
+"submit_bio(rw=%d,0x%x, bi_vcnt=%u, bi_sector=%llu (bytenr %llu), bi_bdev=%p)\n",
+                      bio_op(bio), bio->bi_opf, segs,
+                      bio->bi_iter.bi_sector, dev_bytenr, bio->bi_bdev);
+
+       mapped_datav = kmalloc_array(segs, sizeof(*mapped_datav), GFP_NOFS);
+       if (!mapped_datav)
+               return;
+
+       bio_for_each_segment(bvec, bio, iter) {
+               BUG_ON(bvec.bv_len != PAGE_SIZE);
+               mapped_datav[i] = page_address(bvec.bv_page);
+               i++;
+
+               if (dev_state->state->print_mask &
+                   BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH_VERBOSE)
+                       pr_info("#%u: bytenr=%llu, len=%u, offset=%u\n",
+                              i, cur_bytenr, bvec.bv_len, bvec.bv_offset);
+               cur_bytenr += bvec.bv_len;
+       }
+
+       btrfsic_process_written_block(dev_state, dev_bytenr, mapped_datav, segs,
+                                     bio, &bio_is_patched, bio->bi_opf);
+       kfree(mapped_datav);
+}
+
+static void btrfsic_check_flush_bio(struct bio *bio, struct btrfsic_dev_state *dev_state)
+{
+       if (dev_state->state->print_mask & BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
+               pr_info("submit_bio(rw=%d,0x%x FLUSH, bdev=%p)\n",
+                      bio_op(bio), bio->bi_opf, bio->bi_bdev);
+
+       if (dev_state->dummy_block_for_bio_bh_flush.is_iodone) {
+               struct btrfsic_block *const block =
+                       &dev_state->dummy_block_for_bio_bh_flush;
+
+               block->is_iodone = 0;
+               block->never_written = 0;
+               block->iodone_w_error = 0;
+               block->flush_gen = dev_state->last_flush_gen + 1;
+               block->submit_bio_bh_rw = bio->bi_opf;
+               block->orig_bio_private = bio->bi_private;
+               block->orig_bio_end_io = bio->bi_end_io;
+               block->next_in_same_bio = NULL;
+               bio->bi_private = block;
+               bio->bi_end_io = btrfsic_bio_end_io;
+       } else if ((dev_state->state->print_mask &
+                  (BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH |
+                   BTRFSIC_PRINT_MASK_VERBOSE))) {
+               pr_info(
+"btrfsic_submit_bio(%pg) with FLUSH but dummy block already in use (ignored)!\n",
+                      dev_state->bdev);
+       }
+}
+
 static void __btrfsic_submit_bio(struct bio *bio)
 {
        struct btrfsic_dev_state *dev_state;
@@ -2640,80 +2707,18 @@ static void __btrfsic_submit_bio(struct bio *bio)
        if (!btrfsic_is_initialized)
                return;
 
-       mutex_lock(&btrfsic_mutex);
-       /* since btrfsic_submit_bio() is also called before
-        * btrfsic_mount(), this might return NULL */
+       /*
+        * We can be called before btrfsic_mount, so there might not be a
+        * dev_state.
+        */
        dev_state = btrfsic_dev_state_lookup(bio->bi_bdev->bd_dev);
-       if (NULL != dev_state &&
-           (bio_op(bio) == REQ_OP_WRITE) && bio_has_data(bio)) {
-               int i = 0;
-               u64 dev_bytenr;
-               u64 cur_bytenr;
-               struct bio_vec bvec;
-               struct bvec_iter iter;
-               int bio_is_patched;
-               char **mapped_datav;
-               unsigned int segs = bio_segments(bio);
-
-               dev_bytenr = 512 * bio->bi_iter.bi_sector;
-               bio_is_patched = 0;
-               if (dev_state->state->print_mask &
-                   BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
-                       pr_info("submit_bio(rw=%d,0x%x, bi_vcnt=%u, bi_sector=%llu (bytenr %llu), bi_bdev=%p)\n",
-                              bio_op(bio), bio->bi_opf, segs,
-                              bio->bi_iter.bi_sector, dev_bytenr, bio->bi_bdev);
-
-               mapped_datav = kmalloc_array(segs,
-                                            sizeof(*mapped_datav), GFP_NOFS);
-               if (!mapped_datav)
-                       goto leave;
-               cur_bytenr = dev_bytenr;
-
-               bio_for_each_segment(bvec, bio, iter) {
-                       BUG_ON(bvec.bv_len != PAGE_SIZE);
-                       mapped_datav[i] = page_address(bvec.bv_page);
-                       i++;
-
-                       if (dev_state->state->print_mask &
-                           BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH_VERBOSE)
-                               pr_info("#%u: bytenr=%llu, len=%u, offset=%u\n",
-                                      i, cur_bytenr, bvec.bv_len, bvec.bv_offset);
-                       cur_bytenr += bvec.bv_len;
-               }
-               btrfsic_process_written_block(dev_state, dev_bytenr,
-                                             mapped_datav, segs,
-                                             bio, &bio_is_patched,
-                                             bio->bi_opf);
-               kfree(mapped_datav);
-       } else if (NULL != dev_state && (bio->bi_opf & REQ_PREFLUSH)) {
-               if (dev_state->state->print_mask &
-                   BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH)
-                       pr_info("submit_bio(rw=%d,0x%x FLUSH, bdev=%p)\n",
-                              bio_op(bio), bio->bi_opf, bio->bi_bdev);
-               if (!dev_state->dummy_block_for_bio_bh_flush.is_iodone) {
-                       if ((dev_state->state->print_mask &
-                            (BTRFSIC_PRINT_MASK_SUBMIT_BIO_BH |
-                             BTRFSIC_PRINT_MASK_VERBOSE)))
-                               pr_info(
-"btrfsic_submit_bio(%pg) with FLUSH but dummy block already in use (ignored)!\n",
-                                      dev_state->bdev);
-               } else {
-                       struct btrfsic_block *const block =
-                               &dev_state->dummy_block_for_bio_bh_flush;
-
-                       block->is_iodone = 0;
-                       block->never_written = 0;
-                       block->iodone_w_error = 0;
-                       block->flush_gen = dev_state->last_flush_gen + 1;
-                       block->submit_bio_bh_rw = bio->bi_opf;
-                       block->orig_bio_private = bio->bi_private;
-                       block->orig_bio_end_io = bio->bi_end_io;
-                       block->next_in_same_bio = NULL;
-                       bio->bi_private = block;
-                       bio->bi_end_io = btrfsic_bio_end_io;
-               }
+       mutex_lock(&btrfsic_mutex);
+       if (dev_state) {
+               if (bio_op(bio) == REQ_OP_WRITE && bio_has_data(bio))
+                       btrfsic_check_write_bio(bio, dev_state);
+               else if (bio->bi_opf & REQ_PREFLUSH)
+                       btrfsic_check_flush_bio(bio, dev_state);
        }
-leave:
        mutex_unlock(&btrfsic_mutex);
 }