X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Fbio.c;h=124b95c4d58286649d8d0f982edd9074af18ac82;hb=363911d027d1de1c6df79eb3f487f5476b9619f4;hp=0146f80789e96210c681a043590c1c5932eb49f0;hpb=bb799ca0202a360fa74d5f17039b9100caebdde7;p=safe%2Fjmp%2Flinux-2.6

diff --git a/fs/bio.c b/fs/bio.c
index 0146f80..124b95c 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -31,6 +31,12 @@
 
 DEFINE_TRACE(block_split);
 
+/*
+ * Test patch to inline a certain number of bi_io_vec's inside the bio
+ * itself, to shrink a bio data allocation from two mempool calls to one
+ */
+#define BIO_INLINE_VECS		4
+
 static mempool_t *bio_split_pool __read_mostly;
 
 /*
@@ -174,7 +180,7 @@ struct bio_vec *bvec_alloc_bs(gfp_t gfp_mask, int nr, unsigned long *idx,
 	 * kzalloc() for the exact number of vecs right away.
 	 */
 	if (!bs)
-		bvl = kzalloc(nr * sizeof(struct bio_vec), gfp_mask);
+		bvl = kmalloc(nr * sizeof(struct bio_vec), gfp_mask);
 
 	/*
 	 * see comment near bvec_array define!
@@ -231,9 +237,6 @@ fallback:
 		}
 	}
 
-	if (bvl)
-		memset(bvl, 0, bvec_nr_vecs(*idx) * sizeof(struct bio_vec));
-
 	return bvl;
 }
 
@@ -241,7 +244,7 @@ void bio_free(struct bio *bio, struct bio_set *bs)
 {
 	void *p;
 
-	if (bio->bi_io_vec)
+	if (bio_has_allocated_vec(bio))
 		bvec_free_bs(bs, bio->bi_io_vec, BIO_POOL_IDX(bio));
 
 	if (bio_integrity(bio))
@@ -267,7 +270,8 @@ static void bio_fs_destructor(struct bio *bio)
 
 static void bio_kmalloc_destructor(struct bio *bio)
 {
-	kfree(bio->bi_io_vec);
+	if (bio_has_allocated_vec(bio))
+		kfree(bio->bi_io_vec);
 	kfree(bio);
 }
 
@@ -298,9 +302,10 @@ void bio_init(struct bio *bio)
 struct bio *bio_alloc_bioset(gfp_t gfp_mask, int nr_iovecs, struct bio_set *bs)
 {
 	struct bio *bio = NULL;
+	void *uninitialized_var(p);
 
 	if (bs) {
-		void *p = mempool_alloc(bs->bio_pool, gfp_mask);
+		p = mempool_alloc(bs->bio_pool, gfp_mask);
 
 		if (p)
 			bio = p + bs->front_pad;
@@ -314,17 +319,25 @@ struct bio *bio_alloc_bioset(gfp_t gfp_mask, int nr_iovecs, struct bio_set *bs)
 		if (likely(nr_iovecs)) {
 			unsigned long uninitialized_var(idx);
 
-			bvl = bvec_alloc_bs(gfp_mask, nr_iovecs, &idx, bs);
+			if (nr_iovecs <= BIO_INLINE_VECS) {
+				idx = 0;
+				bvl = bio->bi_inline_vecs;
+				nr_iovecs = BIO_INLINE_VECS;
+			} else {
+				bvl = bvec_alloc_bs(gfp_mask, nr_iovecs, &idx,
+							bs);
+				nr_iovecs = bvec_nr_vecs(idx);
+			}
 			if (unlikely(!bvl)) {
 				if (bs)
-					mempool_free(bio, bs->bio_pool);
+					mempool_free(p, bs->bio_pool);
 				else
 					kfree(bio);
 				bio = NULL;
 				goto out;
 			}
 			bio->bi_flags |= idx << BIO_POOL_OFFSET;
-			bio->bi_max_vecs = bvec_nr_vecs(idx);
+			bio->bi_max_vecs = nr_iovecs;
 		}
 		bio->bi_io_vec = bvl;
 	}
@@ -776,6 +789,7 @@ struct bio *bio_copy_user_iov(struct request_queue *q,
 	int i, ret;
 	int nr_pages = 0;
 	unsigned int len = 0;
+	unsigned int offset = map_data ? map_data->offset & ~PAGE_MASK : 0;
 
 	for (i = 0; i < iov_count; i++) {
 		unsigned long uaddr;
@@ -802,35 +816,42 @@ struct bio *bio_copy_user_iov(struct request_queue *q,
 	bio->bi_rw |= (!write_to_vm << BIO_RW);
 
 	ret = 0;
-	i = 0;
+
+	if (map_data) {
+		nr_pages = 1 << map_data->page_order;
+		i = map_data->offset / PAGE_SIZE;
+	}
 	while (len) {
-		unsigned int bytes;
+		unsigned int bytes = PAGE_SIZE;
 
-		if (map_data)
-			bytes = 1U << (PAGE_SHIFT + map_data->page_order);
-		else
-			bytes = PAGE_SIZE;
+		bytes -= offset;
 
 		if (bytes > len)
 			bytes = len;
 
 		if (map_data) {
-			if (i == map_data->nr_entries) {
+			if (i == map_data->nr_entries * nr_pages) {
 				ret = -ENOMEM;
 				break;
 			}
-			page = map_data->pages[i++];
-		} else
+
+			page = map_data->pages[i / nr_pages];
+			page += (i % nr_pages);
+
+			i++;
+		} else {
 			page = alloc_page(q->bounce_gfp | gfp_mask);
-		if (!page) {
-			ret = -ENOMEM;
-			break;
+			if (!page) {
+				ret = -ENOMEM;
+				break;
+			}
 		}
 
-		if (bio_add_pc_page(q, bio, page, bytes, 0) < bytes)
+		if (bio_add_pc_page(q, bio, page, bytes, offset) < bytes)
 			break;
 
 		len -= bytes;
+		offset = 0;
 	}
 
 	if (ret)
@@ -839,7 +860,7 @@ struct bio *bio_copy_user_iov(struct request_queue *q,
 	/*
 	 * success
 	 */
-	if (!write_to_vm) {
+	if (!write_to_vm && (!map_data || !map_data->null_mapped)) {
 		ret = __bio_copy_iov(bio, bio->bi_io_vec, iov, iov_count, 0, 0);
 		if (ret)
 			goto cleanup;
@@ -1525,6 +1546,7 @@ void bioset_free(struct bio_set *bs)
  */
 struct bio_set *bioset_create(unsigned int pool_size, unsigned int front_pad)
 {
+	unsigned int back_pad = BIO_INLINE_VECS * sizeof(struct bio_vec);
 	struct bio_set *bs;
 
 	bs = kzalloc(sizeof(*bs), GFP_KERNEL);
@@ -1533,7 +1555,7 @@ struct bio_set *bioset_create(unsigned int pool_size, unsigned int front_pad)
 
 	bs->front_pad = front_pad;
 
-	bs->bio_slab = bio_find_or_create_slab(front_pad);
+	bs->bio_slab = bio_find_or_create_slab(front_pad + back_pad);
 	if (!bs->bio_slab) {
 		kfree(bs);
 		return NULL;