Btrfs: fix abnormal long waiting in fsync

[karo-tx-linux.git] / fs / bio-integrity.c

diff --git a/fs/bio-integrity.c b/fs/bio-integrity.c
index 4f70f383132cc9dfe143c570fbb9759967fefc6f..1c2ce0c8771133194ecb9d91517a7dd67c571765 100644 (file)
--- a/fs/bio-integrity.c
+++ b/fs/bio-integrity.c
@@ -182,6 +182,9 @@ static int bdev_integrity_enabled(struct block_device *bdev, int rw)
  */
 int bio_integrity_enabled(struct bio *bio)
 {
+       if (!bio_is_rw(bio))
+               return 0;
+
        /* Already protected? */
        if (bio_integrity(bio))
                return 0;
@@ -301,45 +304,65 @@ int bio_integrity_get_tag(struct bio *bio, void *tag_buf, unsigned int len)
 EXPORT_SYMBOL(bio_integrity_get_tag);
 
 /**
- * bio_integrity_generate - Generate integrity metadata for a bio
- * @bio:       bio to generate integrity metadata for
- *
- * Description: Generates integrity metadata for a bio by calling the
- * block device's generation callback function.  The bio must have a
- * bip attached with enough room to accommodate the generated
- * integrity metadata.
+ * bio_integrity_generate_verify - Generate/verify integrity metadata for a bio
+ * @bio:       bio to generate/verify integrity metadata for
+ * @operate:   operate number, 1 for generate, 0 for verify
  */
-static void bio_integrity_generate(struct bio *bio)
+static int bio_integrity_generate_verify(struct bio *bio, int operate)
 {
        struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
        struct blk_integrity_exchg bix;
-       struct bio_vec bv;
-       struct bvec_iter iter;
-       sector_t sector = bio->bi_iter.bi_sector;
-       unsigned int sectors, total;
+       struct bio_vec *bv;
+       sector_t sector;
+       unsigned int sectors, ret = 0, i;
        void *prot_buf = bio->bi_integrity->bip_buf;
 
-       total = 0;
+       if (operate)
+               sector = bio->bi_iter.bi_sector;
+       else
+               sector = bio->bi_integrity->bip_iter.bi_sector;
+
        bix.disk_name = bio->bi_bdev->bd_disk->disk_name;
        bix.sector_size = bi->sector_size;
 
-       bio_for_each_segment(bv, bio, iter) {
-               void *kaddr = kmap_atomic(bv.bv_page);
-               bix.data_buf = kaddr + bv.bv_offset;
-               bix.data_size = bv.bv_len;
+       bio_for_each_segment_all(bv, bio, i) {
+               void *kaddr = kmap_atomic(bv->bv_page);
+               bix.data_buf = kaddr + bv->bv_offset;
+               bix.data_size = bv->bv_len;
                bix.prot_buf = prot_buf;
                bix.sector = sector;
 
-               bi->generate_fn(&bix);
+               if (operate)
+                       bi->generate_fn(&bix);
+               else {
+                       ret = bi->verify_fn(&bix);
+                       if (ret) {
+                               kunmap_atomic(kaddr);
+                               return ret;
+                       }
+               }
 
-               sectors = bv.bv_len / bi->sector_size;
+               sectors = bv->bv_len / bi->sector_size;
                sector += sectors;
                prot_buf += sectors * bi->tuple_size;
-               total += sectors * bi->tuple_size;
-               BUG_ON(total > bio->bi_integrity->bip_iter.bi_size);
 
                kunmap_atomic(kaddr);
        }
+       return ret;
+}
+
+/**
+ * bio_integrity_generate - Generate integrity metadata for a bio
+ * @bio:       bio to generate integrity metadata for
+ *
+ * Description: Generates integrity metadata for a bio by calling the
+ * block device's generation callback function.  The bio must have a
+ * bip attached with enough room to accommodate the generated
+ * integrity metadata.
+ */
+static void bio_integrity_generate(struct bio *bio)
+{
+       bio_integrity_generate_verify(bio, 1);
 }
 
 static inline unsigned short blk_integrity_tuple_size(struct blk_integrity *bi)
@@ -454,40 +477,7 @@ EXPORT_SYMBOL(bio_integrity_prep);
  */
 static int bio_integrity_verify(struct bio *bio)
 {
-       struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
-       struct blk_integrity_exchg bix;
-       struct bio_vec *bv;
-       sector_t sector = bio->bi_integrity->bip_iter.bi_sector;
-       unsigned int sectors, ret = 0;
-       void *prot_buf = bio->bi_integrity->bip_buf;
-       int i;
-
-       bix.disk_name = bio->bi_bdev->bd_disk->disk_name;
-       bix.sector_size = bi->sector_size;
-
-       bio_for_each_segment_all(bv, bio, i) {
-               void *kaddr = kmap_atomic(bv->bv_page);
-
-               bix.data_buf = kaddr + bv->bv_offset;
-               bix.data_size = bv->bv_len;
-               bix.prot_buf = prot_buf;
-               bix.sector = sector;
-
-               ret = bi->verify_fn(&bix);
-
-               if (ret) {
-                       kunmap_atomic(kaddr);
-                       return ret;
-               }
-
-               sectors = bv->bv_len / bi->sector_size;
-               sector += sectors;
-               prot_buf += sectors * bi->tuple_size;
-
-               kunmap_atomic(kaddr);
-       }
-
-       return ret;
+       return bio_integrity_generate_verify(bio, 0);
 }
 
 /**