CHROMIUM: md: dm-bootcache: reinitialize bio structure

[cascardo/linux.git] / drivers / md / dm-bootcache.c

diff --git a/drivers/md/dm-bootcache.c b/drivers/md/dm-bootcache.c
index d83337d..c6c0269 100644 (file)
--- a/drivers/md/dm-bootcache.c
+++ b/drivers/md/dm-bootcache.c
@@ -577,15 +577,15 @@ static int bootcache_read_sectors(struct bootcache *cache)
        int j;
        int rc = 0;
 
-       bio = bio_alloc_bioset(GFP_KERNEL, max_io, cache->bio_set);
-       if (unlikely(!bio)) {
-               DMERR("Out of memory bio_alloc_bioset");
-               return -ENOMEM;
-       }
-       bio->bi_private = &waiter;
-       bio->bi_destructor = bootcache_bio_destructor;
        p = cache->sectors.pages;
        for (i = 0; i < chunks_to_read; i++) {
+               bio = bio_alloc_bioset(GFP_KERNEL, max_io, cache->bio_set);
+               if (unlikely(!bio)) {
+                       DMERR("Out of memory bio_alloc_bioset");
+                       return -ENOMEM;
+               }
+               bio->bi_private = &waiter;
+               bio->bi_destructor = bootcache_bio_destructor;
                bio->bi_idx = 0;
                bio->bi_bdev = cache->dev->bdev;
                bio->bi_end_io = bootcache_read_sectors_end;
@@ -609,6 +609,8 @@ static int bootcache_read_sectors(struct bootcache *cache)
                wait_for_completion(&waiter.completion);
                if (waiter.error) {
                        rc = waiter.error;
+                       bio->bi_private = cache;
+                       bio_put(bio);
                        break;
                }
                p = start_page;
@@ -618,9 +620,9 @@ static int bootcache_read_sectors(struct bootcache *cache)
                        p->is_filled = 1;
                }
                sector += pages_to_sectors(j);
+               bio->bi_private = cache;
+               bio_put(bio);
        }
-       bio->bi_private = cache;
-       bio_put(bio);
        atomic_set(&cache->state, BC_FILLED);
        return rc;
 }
@@ -645,7 +647,6 @@ static int bootcache_dev_read(struct bootcache *cache, void *data,
        struct bio_vec *bvec;
        int pages_to_read = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
        int max_io = cache->max_io;
-       int num_pages;
        int bytes_to_copy;
        int i;
        int rc = 0;
@@ -653,24 +654,20 @@ static int bootcache_dev_read(struct bootcache *cache, void *data,
        u8 *dst = data;
        u8 *src;
 
-       if (pages_to_read < max_io)
-               num_pages = pages_to_read;
-       else
-               num_pages = max_io;
-       bio = bio_alloc_bioset(GFP_KERNEL, num_pages, cache->bio_set);
-       if (unlikely(!bio)) {
-               DMERR("Out of memory bio_alloc_bioset");
-               return -ENOMEM;
-       }
-       bvec = bio->bi_io_vec;
-       for (i = 0; i < num_pages; i++, bvec++)
-               bvec->bv_page = alloc_page(GFP_KERNEL);
-       bio->bi_private = &waiter;
-       bio->bi_destructor = bootcache_bio_destructor;
        pages_read = 0;
        while (len) {
                if (pages_to_read < max_io)
                        max_io = pages_to_read;
+               bio = bio_alloc_bioset(GFP_KERNEL, max_io, cache->bio_set);
+               if (unlikely(!bio)) {
+                       DMERR("Out of memory bio_alloc_bioset");
+                       return -ENOMEM;
+               }
+               bvec = bio->bi_io_vec;
+               for (i = 0; i < max_io; i++, bvec++)
+                       bvec->bv_page = alloc_page(GFP_KERNEL);
+               bio->bi_private = &waiter;
+               bio->bi_destructor = bootcache_bio_destructor;
                bio->bi_idx = 0;
                bio->bi_bdev = cache->dev->bdev;
                bio->bi_end_io = bootcache_dev_read_end;
@@ -691,10 +688,10 @@ static int bootcache_dev_read(struct bootcache *cache, void *data,
                wait_for_completion(&waiter.completion);
                if (waiter.error) {
                        rc = waiter.error;
-                       goto exit;
+                       goto error;
                }
                for (i = 0; i < max_io; i++) {
-                       bytes_to_copy = (len < PAGE_SIZE) ? len : PAGE_SIZE;
+                       bytes_to_copy = min(len, (int)PAGE_SIZE);
                        src = kmap_atomic(bio_iovec_idx(bio, i)->bv_page);
                        memcpy(dst, src, bytes_to_copy);
                        kunmap_atomic(src);
@@ -704,10 +701,16 @@ static int bootcache_dev_read(struct bootcache *cache, void *data,
                        dst += bytes_to_copy;
                }
                sector += pages_to_sectors(max_io);
+               bvec = bio->bi_io_vec;
+               for (i = 0; i < max_io; i++, bvec++)
+                       __free_pages(bvec->bv_page, 0);
+               bio->bi_private = cache;
+               bio_put(bio);
        }
-exit:
+       return rc;
+error:
        bvec = bio->bi_io_vec;
-       for (i = 0; i < num_pages; i++, bvec++)
+       for (i = 0; i < max_io; i++, bvec++)
                __free_pages(bvec->bv_page, 0);
        bio->bi_private = cache;
        bio_put(bio);