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 ea1bf53..f103729 100644 (file)
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -41,10 +41,10 @@ static int __blk_rq_unmap_user(struct bio *bio)
 }
 
 static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
-                            void __user *ubuf, unsigned int len)
+                            struct rq_map_data *map_data, void __user *ubuf,
+                            unsigned int len, gfp_t gfp_mask)
 {
        unsigned long uaddr;
-       unsigned int alignment;
        struct bio *bio, *orig_bio;
        int reading, ret;
 
@@ -55,15 +55,17 @@ 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))
-               bio = bio_map_user(q, NULL, uaddr, len, reading);
+       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, uaddr, len, reading);
+               bio = bio_copy_user(q, map_data, uaddr, len, reading, gfp_mask);
 
        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);
 
@@ -88,8 +90,10 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
  * blk_rq_map_user - map user data to a request, for REQ_TYPE_BLOCK_PC usage
  * @q:         request queue where request should be inserted
  * @rq:                request structure to fill
+ * @map_data:   pointer to the rq_map_data holding pages (if necessary)
  * @ubuf:      the user buffer
  * @len:       length of user data
+ * @gfp_mask:  memory allocation flags
  *
  * Description:
  *    Data will be mapped directly for zero copy I/O, if possible. Otherwise
@@ -105,7 +109,8 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
  *    unmapping.
  */
 int blk_rq_map_user(struct request_queue *q, struct request *rq,
-                   void __user *ubuf, unsigned long len)
+                   struct rq_map_data *map_data, void __user *ubuf,
+                   unsigned long len, gfp_t gfp_mask)
 {
        unsigned long bytes_read = 0;
        struct bio *bio = NULL;
@@ -113,7 +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) {
@@ -132,13 +140,17 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq,
                if (end - start > BIO_MAX_PAGES)
                        map_len -= PAGE_SIZE;
 
-               ret = __blk_rq_map_user(q, rq, ubuf, map_len);
+               ret = __blk_rq_map_user(q, rq, map_data, ubuf, map_len,
+                                       gfp_mask);
                if (ret < 0)
                        goto unmap_rq;
                if (!bio)
                        bio = rq->bio;
                bytes_read += ret;
                ubuf += ret;
+
+               if (map_data)
+                       map_data->offset += ret;
        }
 
        if (!bio_flagged(bio, BIO_USER_MAPPED))
@@ -157,9 +169,11 @@ EXPORT_SYMBOL(blk_rq_map_user);
  * blk_rq_map_user_iov - map user data to a request, for REQ_TYPE_BLOCK_PC usage
  * @q:         request queue where request should be inserted
  * @rq:                request to map data to
+ * @map_data:   pointer to the rq_map_data holding pages (if necessary)
  * @iov:       pointer to the iovec
  * @iov_count: number of elements in the iovec
  * @len:       I/O byte count
+ * @gfp_mask:  memory allocation flags
  *
  * Description:
  *    Data will be mapped directly for zero copy I/O, if possible. Otherwise
@@ -175,7 +189,8 @@ EXPORT_SYMBOL(blk_rq_map_user);
  *    unmapping.
  */
 int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
-                       struct sg_iovec *iov, int iov_count, unsigned int len)
+                       struct rq_map_data *map_data, struct sg_iovec *iov,
+                       int iov_count, unsigned int len, gfp_t gfp_mask)
 {
        struct bio *bio;
        int i, read = rq_data_dir(rq) == READ;
@@ -193,17 +208,24 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
                }
        }
 
-       if (unaligned || (q->dma_pad_mask & len))
-               bio = bio_copy_user_iov(q, iov, iov_count, read);
+       if (unaligned || (q->dma_pad_mask & len) || map_data)
+               bio = bio_copy_user_iov(q, map_data, iov, iov_count, read,
+                                       gfp_mask);
        else
-               bio = bio_map_user_iov(q, NULL, iov, iov_count, read);
+               bio = bio_map_user_iov(q, NULL, iov, iov_count, read, gfp_mask);
 
        if (IS_ERR(bio))
                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;
        }
 
@@ -216,6 +238,7 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
        rq->buffer = rq->data = NULL;
        return 0;
 }
+EXPORT_SYMBOL(blk_rq_map_user_iov);
 
 /**
  * blk_rq_unmap_user - unmap a request with user data
@@ -264,8 +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;
@@ -275,11 +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