fuse: switch to iov_iter_get_pages()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2014-03-16 16:08:30 -04:00
parent d22a943f44
commit c9c37e2e63

View file

@ -1294,7 +1294,7 @@ static int fuse_get_user_pages(struct fuse_req *req, struct iov_iter *ii,
size_t nbytes = 0; /* # bytes already packed in req */
/* Special case for kernel I/O: can copy directly into the buffer */
if (segment_eq(get_fs(), KERNEL_DS)) {
if (ii->type & REQ_KERNEL) {
unsigned long user_addr = fuse_get_user_addr(ii);
size_t frag_size = fuse_get_frag_size(ii, *nbytesp);
@ -1310,35 +1310,26 @@ static int fuse_get_user_pages(struct fuse_req *req, struct iov_iter *ii,
while (nbytes < *nbytesp && req->num_pages < req->max_pages) {
unsigned npages;
unsigned long user_addr = fuse_get_user_addr(ii);
unsigned offset = user_addr & ~PAGE_MASK;
size_t frag_size = fuse_get_frag_size(ii, *nbytesp - nbytes);
int ret;
size_t start, end, frag_size;
unsigned n = req->max_pages - req->num_pages;
frag_size = min_t(size_t, frag_size, n << PAGE_SHIFT);
npages = (frag_size + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
npages = clamp(npages, 1U, n);
ret = get_user_pages_fast(user_addr, npages, !write,
&req->pages[req->num_pages]);
ssize_t ret = iov_iter_get_pages(ii,
&req->pages[req->num_pages],
n * PAGE_SIZE, &start);
if (ret < 0)
return ret;
npages = ret;
frag_size = min_t(size_t, frag_size,
(npages << PAGE_SHIFT) - offset);
iov_iter_advance(ii, frag_size);
iov_iter_advance(ii, ret);
nbytes += ret;
req->page_descs[req->num_pages].offset = offset;
ret += start;
npages = (ret + PAGE_SIZE - 1) / PAGE_SIZE;
req->page_descs[req->num_pages].offset = start;
fuse_page_descs_length_init(req, req->num_pages, npages);
req->num_pages += npages;
req->page_descs[req->num_pages - 1].length -=
(npages << PAGE_SHIFT) - offset - frag_size;
nbytes += frag_size;
(PAGE_SIZE - ret) & (PAGE_SIZE - 1);
}
if (write)