Revert "bio: modify __bio_add_page() to accept pages that don't start a new segment"
This reverts commit 254c4407cb84a6dec90336054615b0f0e996bb7c.
It causes crashes with cryptsetup, even after a few iterations and
updates. Drop it for now.
diff --git a/block/bio.c b/block/bio.c
index fb12df9..0ec61c9 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -744,7 +744,6 @@
}
}
- bio->bi_iter.bi_size += len;
goto done;
}
@@ -761,6 +760,20 @@
return 0;
/*
+ * we might lose a segment or two here, but rather that than
+ * make this too complex.
+ */
+
+ while (bio->bi_phys_segments >= queue_max_segments(q)) {
+
+ if (retried_segments)
+ return 0;
+
+ retried_segments = 1;
+ blk_recount_segments(q, bio);
+ }
+
+ /*
* setup the new entry, we might clear it again later if we
* cannot add the page
*/
@@ -768,23 +781,6 @@
bvec->bv_page = page;
bvec->bv_len = len;
bvec->bv_offset = offset;
- bio->bi_vcnt++;
- bio->bi_phys_segments++;
- bio->bi_iter.bi_size += len;
-
- /*
- * Perform a recount if the number of segments is greater
- * than queue_max_segments(q).
- */
-
- while (bio->bi_phys_segments > queue_max_segments(q)) {
-
- if (retried_segments)
- goto failed;
-
- retried_segments = 1;
- blk_recount_segments(q, bio);
- }
/*
* if queue has other restrictions (eg varying max sector size
@@ -803,25 +799,23 @@
* merge_bvec_fn() returns number of bytes it can accept
* at this offset
*/
- if (q->merge_bvec_fn(q, &bvm, bvec) < bvec->bv_len)
- goto failed;
+ if (q->merge_bvec_fn(q, &bvm, bvec) < bvec->bv_len) {
+ bvec->bv_page = NULL;
+ bvec->bv_len = 0;
+ bvec->bv_offset = 0;
+ return 0;
+ }
}
/* If we may be able to merge these biovecs, force a recount */
- if (bio->bi_vcnt > 1 && (BIOVEC_PHYS_MERGEABLE(bvec-1, bvec)))
+ if (bio->bi_vcnt && (BIOVEC_PHYS_MERGEABLE(bvec-1, bvec)))
bio->bi_flags &= ~(1 << BIO_SEG_VALID);
+ bio->bi_vcnt++;
+ bio->bi_phys_segments++;
done:
+ bio->bi_iter.bi_size += len;
return len;
-
- failed:
- bvec->bv_page = NULL;
- bvec->bv_len = 0;
- bvec->bv_offset = 0;
- bio->bi_vcnt--;
- bio->bi_iter.bi_size -= len;
- blk_recount_segments(q, bio);
- return 0;
}
/**