xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

switch iov_iter_get_pages() to passing maximal number of pages

Browse Source 
... instead of maximal size.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro
2014-06-18 20:34:33 -04:00
parent 49c7dd287a
commit c7f3888ad7
4 changed files with 12 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

17
mm/iov_iter.c
View File

@@ -310,7 +310,7 @@ void iov_iter_init(struct iov_iter *i, int direction,
EXPORT_SYMBOL(iov_iter_init);
static ssize_t get_pages_iovec(struct iov_iter *i,
struct page **pages, size_t maxsize,
struct page **pages, unsigned maxpages,
size_t *start)
{
size_t offset = i->iov_offset;
@@ -323,10 +323,10 @@ static ssize_t get_pages_iovec(struct iov_iter *i,
len = iov->iov_len - offset;
if (len > i->count)
len = i->count;
if (len > maxsize)
len = maxsize;
addr = (unsigned long)iov->iov_base + offset;
len += *start = addr & (PAGE_SIZE - 1);
if (len > maxpages * PAGE_SIZE)
len = maxpages * PAGE_SIZE;
addr &= ~(PAGE_SIZE - 1);
n = (len + PAGE_SIZE - 1) / PAGE_SIZE;
res = get_user_pages_fast(addr, n, (i->type & WRITE) != WRITE, pages);
@@ -588,15 +588,14 @@ static unsigned long alignment_bvec(const struct iov_iter *i)
}
static ssize_t get_pages_bvec(struct iov_iter *i,
struct page **pages, size_t maxsize,
struct page **pages, unsigned maxpages,
size_t *start)
{
const struct bio_vec *bvec = i->bvec;
size_t len = bvec->bv_len - i->iov_offset;
if (len > i->count)
len = i->count;
if (len > maxsize)
len = maxsize;
/* can't be more than PAGE_SIZE */
*start = bvec->bv_offset + i->iov_offset;
get_page(*pages = bvec->bv_page);
@@ -712,13 +711,13 @@ unsigned long iov_iter_alignment(const struct iov_iter *i)
EXPORT_SYMBOL(iov_iter_alignment);
ssize_t iov_iter_get_pages(struct iov_iter *i,
struct page **pages, size_t maxsize,
struct page **pages, unsigned maxpages,
size_t *start)
{
if (i->type & ITER_BVEC)
return get_pages_bvec(i, pages, maxsize, start);
return get_pages_bvec(i, pages, maxpages, start);
else
return get_pages_iovec(i, pages, maxsize, start);
return get_pages_iovec(i, pages, maxpages, start);
}
EXPORT_SYMBOL(iov_iter_get_pages);