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Diffstat (limited to 'drivers/vhost/scsi.c')
-rw-r--r--drivers/vhost/scsi.c73
1 files changed, 23 insertions, 50 deletions
diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
index 1bc9be829fb4..71517b3c5558 100644
--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -210,12 +210,6 @@ static struct workqueue_struct *vhost_scsi_workqueue;
static DEFINE_MUTEX(vhost_scsi_mutex);
static LIST_HEAD(vhost_scsi_list);
-static int iov_num_pages(void __user *iov_base, size_t iov_len)
-{
- return (PAGE_ALIGN((unsigned long)iov_base + iov_len) -
- ((unsigned long)iov_base & PAGE_MASK)) >> PAGE_SHIFT;
-}
-
static void vhost_scsi_done_inflight(struct kref *kref)
{
struct vhost_scsi_inflight *inflight;
@@ -618,48 +612,31 @@ vhost_scsi_get_tag(struct vhost_virtqueue *vq, struct vhost_scsi_tpg *tpg,
*/
static int
vhost_scsi_map_to_sgl(struct vhost_scsi_cmd *cmd,
- void __user *ptr,
- size_t len,
+ struct iov_iter *iter,
struct scatterlist *sgl,
bool write)
{
- unsigned int npages = 0, offset, nbytes;
- unsigned int pages_nr = iov_num_pages(ptr, len);
- struct scatterlist *sg = sgl;
struct page **pages = cmd->tvc_upages;
- int ret, i;
-
- if (pages_nr > VHOST_SCSI_PREALLOC_UPAGES) {
- pr_err("vhost_scsi_map_to_sgl() pages_nr: %u greater than"
- " preallocated VHOST_SCSI_PREALLOC_UPAGES: %u\n",
- pages_nr, VHOST_SCSI_PREALLOC_UPAGES);
- return -ENOBUFS;
- }
+ struct scatterlist *sg = sgl;
+ ssize_t bytes;
+ size_t offset;
+ unsigned int npages = 0;
- ret = get_user_pages_fast((unsigned long)ptr, pages_nr, write, pages);
+ bytes = iov_iter_get_pages(iter, pages, LONG_MAX,
+ VHOST_SCSI_PREALLOC_UPAGES, &offset);
/* No pages were pinned */
- if (ret < 0)
- goto out;
- /* Less pages pinned than wanted */
- if (ret != pages_nr) {
- for (i = 0; i < ret; i++)
- put_page(pages[i]);
- ret = -EFAULT;
- goto out;
- }
+ if (bytes <= 0)
+ return bytes < 0 ? bytes : -EFAULT;
- while (len > 0) {
- offset = (uintptr_t)ptr & ~PAGE_MASK;
- nbytes = min_t(unsigned int, PAGE_SIZE - offset, len);
- sg_set_page(sg, pages[npages], nbytes, offset);
- ptr += nbytes;
- len -= nbytes;
- sg++;
- npages++;
- }
+ iov_iter_advance(iter, bytes);
-out:
- return ret;
+ while (bytes) {
+ unsigned n = min_t(unsigned, PAGE_SIZE - offset, bytes);
+ sg_set_page(sg++, pages[npages++], n, offset);
+ bytes -= n;
+ offset = 0;
+ }
+ return npages;
}
static int
@@ -687,24 +664,20 @@ vhost_scsi_iov_to_sgl(struct vhost_scsi_cmd *cmd, bool write,
struct iov_iter *iter,
struct scatterlist *sg, int sg_count)
{
- size_t off = iter->iov_offset;
- int i, ret;
-
- for (i = 0; i < iter->nr_segs; i++) {
- void __user *base = iter->iov[i].iov_base + off;
- size_t len = iter->iov[i].iov_len - off;
+ struct scatterlist *p = sg;
+ int ret;
- ret = vhost_scsi_map_to_sgl(cmd, base, len, sg, write);
+ while (iov_iter_count(iter)) {
+ ret = vhost_scsi_map_to_sgl(cmd, iter, sg, write);
if (ret < 0) {
- for (i = 0; i < sg_count; i++) {
- struct page *page = sg_page(&sg[i]);
+ while (p < sg) {
+ struct page *page = sg_page(p++);
if (page)
put_page(page);
}
return ret;
}
sg += ret;
- off = 0;
}
return 0;
}