nfsd: track last inode only in use_wgather case

[safe/jmp/linux-2.6] / block / blk-map.c

diff --git a/block/blk-map.c b/block/blk-map.c
index dad6a29..f103729 100644 (file)
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -45,7 +45,6 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
                             unsigned int len, gfp_t gfp_mask)
 {
        unsigned long uaddr;
-       unsigned int alignment;
        struct bio *bio, *orig_bio;
        int reading, ret;
 
@@ -56,8 +55,7 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
         * direct dma. else, set up kernel bounce buffers
         */
        uaddr = (unsigned long) ubuf;
-       alignment = queue_dma_alignment(q) | q->dma_pad_mask;
-       if (!(uaddr & alignment) && !(len & alignment) && !map_data)
+       if (blk_rq_aligned(q, ubuf, len) && !map_data)
                bio = bio_map_user(q, NULL, uaddr, len, reading, gfp_mask);
        else
                bio = bio_copy_user(q, map_data, uaddr, len, reading, gfp_mask);
@@ -65,6 +63,9 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
        if (IS_ERR(bio))
                return PTR_ERR(bio);
 
+       if (map_data && map_data->null_mapped)
+               bio->bi_flags |= (1 << BIO_NULL_MAPPED);
+
        orig_bio = bio;
        blk_queue_bounce(q, &bio);
 
@@ -117,7 +118,10 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq,
 
        if (len > (q->max_hw_sectors << 9))
                return -EINVAL;
-       if (!len || !ubuf)
+       if (!len)
+               return -EINVAL;
+
+       if (!ubuf && (!map_data || !map_data->null_mapped))
                return -EINVAL;
 
        while (bytes_read != len) {
@@ -144,6 +148,9 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq,
                        bio = rq->bio;
                bytes_read += ret;
                ubuf += ret;
+
+               if (map_data)
+                       map_data->offset += ret;
        }
 
        if (!bio_flagged(bio, BIO_USER_MAPPED))
@@ -211,8 +218,14 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
                return PTR_ERR(bio);
 
        if (bio->bi_size != len) {
+               /*
+                * Grab an extra reference to this bio, as bio_unmap_user()
+                * expects to be able to drop it twice as it happens on the
+                * normal IO completion path
+                */
+               bio_get(bio);
                bio_endio(bio, 0);
-               bio_unmap_user(bio);
+               __blk_rq_unmap_user(bio);
                return -EINVAL;
        }
 
@@ -274,8 +287,6 @@ EXPORT_SYMBOL(blk_rq_unmap_user);
 int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
                    unsigned int len, gfp_t gfp_mask)
 {
-       unsigned long kaddr;
-       unsigned int alignment;
        int reading = rq_data_dir(rq) == READ;
        int do_copy = 0;
        struct bio *bio;
@@ -285,11 +296,7 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
        if (!len || !kbuf)
                return -EINVAL;
 
-       kaddr = (unsigned long)kbuf;
-       alignment = queue_dma_alignment(q) | q->dma_pad_mask;
-       do_copy = ((kaddr & alignment) || (len & alignment) ||
-                  object_is_on_stack(kbuf));
-
+       do_copy = !blk_rq_aligned(q, kbuf, len) || object_is_on_stack(kbuf);
        if (do_copy)
                bio = bio_copy_kern(q, kbuf, len, gfp_mask, reading);
        else