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-rw-r--r--block/blk-map.c172
1 files changed, 32 insertions, 140 deletions
diff --git a/block/blk-map.c b/block/blk-map.c
index f890d4345b0c..b8d2725324a6 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -5,7 +5,7 @@
#include <linux/module.h>
#include <linux/bio.h>
#include <linux/blkdev.h>
-#include <scsi/sg.h> /* for struct sg_iovec */
+#include <linux/uio.h>
#include "blk.h"
@@ -39,138 +39,12 @@ static int __blk_rq_unmap_user(struct bio *bio)
return ret;
}
-static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
- struct rq_map_data *map_data, void __user *ubuf,
- unsigned int len, gfp_t gfp_mask)
-{
- unsigned long uaddr;
- struct bio *bio, *orig_bio;
- int reading, ret;
-
- reading = rq_data_dir(rq) == READ;
-
- /*
- * if alignment requirement is satisfied, map in user pages for
- * direct dma. else, set up kernel bounce buffers
- */
- uaddr = (unsigned long) ubuf;
- if (blk_rq_aligned(q, uaddr, 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);
-
- 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);
-
- /*
- * We link the bounce buffer in and could have to traverse it
- * later so we have to get a ref to prevent it from being freed
- */
- bio_get(bio);
-
- ret = blk_rq_append_bio(q, rq, bio);
- if (!ret)
- return bio->bi_iter.bi_size;
-
- /* if it was boucned we must call the end io function */
- bio_endio(bio, 0);
- __blk_rq_unmap_user(orig_bio);
- bio_put(bio);
- return ret;
-}
-
-/**
- * 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
- * a kernel bounce buffer is used.
- *
- * A matching blk_rq_unmap_user() must be issued at the end of I/O, while
- * still in process context.
- *
- * Note: The mapped bio may need to be bounced through blk_queue_bounce()
- * before being submitted to the device, as pages mapped may be out of
- * reach. It's the callers responsibility to make sure this happens. The
- * original bio must be passed back in to blk_rq_unmap_user() for proper
- * unmapping.
- */
-int blk_rq_map_user(struct request_queue *q, struct request *rq,
- 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;
- int ret;
-
- if (len > (queue_max_hw_sectors(q) << 9))
- return -EINVAL;
- if (!len)
- return -EINVAL;
-
- if (!ubuf && (!map_data || !map_data->null_mapped))
- return -EINVAL;
-
- while (bytes_read != len) {
- unsigned long map_len, end, start;
-
- map_len = min_t(unsigned long, len - bytes_read, BIO_MAX_SIZE);
- end = ((unsigned long)ubuf + map_len + PAGE_SIZE - 1)
- >> PAGE_SHIFT;
- start = (unsigned long)ubuf >> PAGE_SHIFT;
-
- /*
- * A bad offset could cause us to require BIO_MAX_PAGES + 1
- * pages. If this happens we just lower the requested
- * mapping len by a page so that we can fit
- */
- if (end - start > BIO_MAX_PAGES)
- map_len -= PAGE_SIZE;
-
- 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))
- rq->cmd_flags |= REQ_COPY_USER;
-
- return 0;
-unmap_rq:
- blk_rq_unmap_user(bio);
- rq->bio = NULL;
- return ret;
-}
-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
+ * @iter: iovec iterator
* @gfp_mask: memory allocation flags
*
* Description:
@@ -187,20 +61,21 @@ EXPORT_SYMBOL(blk_rq_map_user);
* unmapping.
*/
int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
- struct rq_map_data *map_data, const struct sg_iovec *iov,
- int iov_count, unsigned int len, gfp_t gfp_mask)
+ struct rq_map_data *map_data,
+ const struct iov_iter *iter, gfp_t gfp_mask)
{
struct bio *bio;
- int i, read = rq_data_dir(rq) == READ;
int unaligned = 0;
+ struct iov_iter i;
+ struct iovec iov;
- if (!iov || iov_count <= 0)
+ if (!iter || !iter->count)
return -EINVAL;
- for (i = 0; i < iov_count; i++) {
- unsigned long uaddr = (unsigned long)iov[i].iov_base;
+ iov_for_each(iov, i, *iter) {
+ unsigned long uaddr = (unsigned long) iov.iov_base;
- if (!iov[i].iov_len)
+ if (!iov.iov_len)
return -EINVAL;
/*
@@ -210,16 +85,18 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
unaligned = 1;
}
- if (unaligned || (q->dma_pad_mask & len) || map_data)
- bio = bio_copy_user_iov(q, map_data, iov, iov_count, read,
- gfp_mask);
+ if (unaligned || (q->dma_pad_mask & iter->count) || map_data)
+ bio = bio_copy_user_iov(q, map_data, iter, gfp_mask);
else
- bio = bio_map_user_iov(q, NULL, iov, iov_count, read, gfp_mask);
+ bio = bio_map_user_iov(q, iter, gfp_mask);
if (IS_ERR(bio))
return PTR_ERR(bio);
- if (bio->bi_iter.bi_size != len) {
+ if (map_data && map_data->null_mapped)
+ bio->bi_flags |= (1 << BIO_NULL_MAPPED);
+
+ if (bio->bi_iter.bi_size != iter->count) {
/*
* Grab an extra reference to this bio, as bio_unmap_user()
* expects to be able to drop it twice as it happens on the
@@ -241,6 +118,21 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
}
EXPORT_SYMBOL(blk_rq_map_user_iov);
+int blk_rq_map_user(struct request_queue *q, struct request *rq,
+ struct rq_map_data *map_data, void __user *ubuf,
+ unsigned long len, gfp_t gfp_mask)
+{
+ struct iovec iov;
+ struct iov_iter i;
+
+ iov.iov_base = ubuf;
+ iov.iov_len = len;
+ iov_iter_init(&i, rq_data_dir(rq), &iov, 1, len);
+
+ return blk_rq_map_user_iov(q, rq, map_data, &i, gfp_mask);
+}
+EXPORT_SYMBOL(blk_rq_map_user);
+
/**
* blk_rq_unmap_user - unmap a request with user data
* @bio: start of bio list