diff mbox series

[30/44] iov_iter: lift dealing with maxpages out of first_{iovec,bvec}_segment()

Message ID 20220622041552.737754-30-viro@zeniv.linux.org.uk (mailing list archive)
State New, archived
Headers show
Series [01/44] 9p: handling Rerror without copy_from_iter_full() | expand

Commit Message

Al Viro June 22, 2022, 4:15 a.m. UTC 
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 lib/iov_iter.c | 23 +++++++++++------------
 1 file changed, 11 insertions(+), 12 deletions(-)

Comments

Jeff Layton June 28, 2022, 11:56 a.m. UTC | #1 
On Wed, 2022-06-22 at 05:15 +0100, Al Viro wrote:
> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
> ---
>  lib/iov_iter.c | 23 +++++++++++------------
>  1 file changed, 11 insertions(+), 12 deletions(-)
> 
> diff --git a/lib/iov_iter.c b/lib/iov_iter.c
> index 92a566f839f9..9ef671b101dc 100644
> --- a/lib/iov_iter.c
> +++ b/lib/iov_iter.c
> @@ -1308,12 +1308,9 @@ static ssize_t iter_xarray_get_pages(struct iov_iter *i,
>  
>  static unsigned long found_ubuf_segment(unsigned long addr,
>  					size_t len,
> -					size_t *size, size_t *start,
> -					unsigned maxpages)
> +					size_t *size, size_t *start)
>  {
>  	len += (*start = addr % PAGE_SIZE);
> -	if (len > maxpages * PAGE_SIZE)
> -		len = maxpages * PAGE_SIZE;
>  	*size = len;
>  	return addr & PAGE_MASK;
>  }
> @@ -1321,14 +1318,14 @@ static unsigned long found_ubuf_segment(unsigned long addr,
>  /* must be done on non-empty ITER_UBUF or ITER_IOVEC one */
>  static unsigned long first_iovec_segment(const struct iov_iter *i,
>  					 size_t *size, size_t *start,
> -					 size_t maxsize, unsigned maxpages)
> +					 size_t maxsize)
>  {
>  	size_t skip;
>  	long k;
>  
>  	if (iter_is_ubuf(i)) {
>  		unsigned long addr = (unsigned long)i->ubuf + i->iov_offset;
> -		return found_ubuf_segment(addr, maxsize, size, start, maxpages);
> +		return found_ubuf_segment(addr, maxsize, size, start);
>  	}
>  
>  	for (k = 0, skip = i->iov_offset; k < i->nr_segs; k++, skip = 0) {
> @@ -1339,7 +1336,7 @@ static unsigned long first_iovec_segment(const struct iov_iter *i,
>  			continue;
>  		if (len > maxsize)
>  			len = maxsize;
> -		return found_ubuf_segment(addr, len, size, start, maxpages);
> +		return found_ubuf_segment(addr, len, size, start);
>  	}
>  	BUG(); // if it had been empty, we wouldn't get called
>  }
> @@ -1347,7 +1344,7 @@ static unsigned long first_iovec_segment(const struct iov_iter *i,
>  /* must be done on non-empty ITER_BVEC one */
>  static struct page *first_bvec_segment(const struct iov_iter *i,
>  				       size_t *size, size_t *start,
> -				       size_t maxsize, unsigned maxpages)
> +				       size_t maxsize)
>  {
>  	struct page *page;
>  	size_t skip = i->iov_offset, len;
> @@ -1358,8 +1355,6 @@ static struct page *first_bvec_segment(const struct iov_iter *i,
>  	skip += i->bvec->bv_offset;
>  	page = i->bvec->bv_page + skip / PAGE_SIZE;
>  	len += (*start = skip % PAGE_SIZE);
> -	if (len > maxpages * PAGE_SIZE)
> -		len = maxpages * PAGE_SIZE;
>  	*size = len;
>  	return page;
>  }
> @@ -1387,7 +1382,9 @@ static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,
>  		if (i->nofault)
>  			gup_flags |= FOLL_NOFAULT;
>  
> -		addr = first_iovec_segment(i, &len, start, maxsize, maxpages);
> +		addr = first_iovec_segment(i, &len, start, maxsize);
> +		if (len > maxpages * PAGE_SIZE)
> +			len = maxpages * PAGE_SIZE;
>  		n = DIV_ROUND_UP(len, PAGE_SIZE);
>  		if (!*pages) {
>  			*pages = get_pages_array(n);
> @@ -1403,7 +1400,9 @@ static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,
>  		struct page **p;
>  		struct page *page;
>  
> -		page = first_bvec_segment(i, &len, start, maxsize, maxpages);
> +		page = first_bvec_segment(i, &len, start, maxsize);
> +		if (len > maxpages * PAGE_SIZE)
> +			len = maxpages * PAGE_SIZE;
>  		n = DIV_ROUND_UP(len, PAGE_SIZE);
>  		p = *pages;
>  		if (!p) {

Reviewed-by: Jeff Layton <jlayton@kernel.org>
diff mbox series

Patch

diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 92a566f839f9..9ef671b101dc 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -1308,12 +1308,9 @@  static ssize_t iter_xarray_get_pages(struct iov_iter *i,
 
 static unsigned long found_ubuf_segment(unsigned long addr,
 					size_t len,
-					size_t *size, size_t *start,
-					unsigned maxpages)
+					size_t *size, size_t *start)
 {
 	len += (*start = addr % PAGE_SIZE);
-	if (len > maxpages * PAGE_SIZE)
-		len = maxpages * PAGE_SIZE;
 	*size = len;
 	return addr & PAGE_MASK;
 }
@@ -1321,14 +1318,14 @@  static unsigned long found_ubuf_segment(unsigned long addr,
 /* must be done on non-empty ITER_UBUF or ITER_IOVEC one */
 static unsigned long first_iovec_segment(const struct iov_iter *i,
 					 size_t *size, size_t *start,
-					 size_t maxsize, unsigned maxpages)
+					 size_t maxsize)
 {
 	size_t skip;
 	long k;
 
 	if (iter_is_ubuf(i)) {
 		unsigned long addr = (unsigned long)i->ubuf + i->iov_offset;
-		return found_ubuf_segment(addr, maxsize, size, start, maxpages);
+		return found_ubuf_segment(addr, maxsize, size, start);
 	}
 
 	for (k = 0, skip = i->iov_offset; k < i->nr_segs; k++, skip = 0) {
@@ -1339,7 +1336,7 @@  static unsigned long first_iovec_segment(const struct iov_iter *i,
 			continue;
 		if (len > maxsize)
 			len = maxsize;
-		return found_ubuf_segment(addr, len, size, start, maxpages);
+		return found_ubuf_segment(addr, len, size, start);
 	}
 	BUG(); // if it had been empty, we wouldn't get called
 }
@@ -1347,7 +1344,7 @@  static unsigned long first_iovec_segment(const struct iov_iter *i,
 /* must be done on non-empty ITER_BVEC one */
 static struct page *first_bvec_segment(const struct iov_iter *i,
 				       size_t *size, size_t *start,
-				       size_t maxsize, unsigned maxpages)
+				       size_t maxsize)
 {
 	struct page *page;
 	size_t skip = i->iov_offset, len;
@@ -1358,8 +1355,6 @@  static struct page *first_bvec_segment(const struct iov_iter *i,
 	skip += i->bvec->bv_offset;
 	page = i->bvec->bv_page + skip / PAGE_SIZE;
 	len += (*start = skip % PAGE_SIZE);
-	if (len > maxpages * PAGE_SIZE)
-		len = maxpages * PAGE_SIZE;
 	*size = len;
 	return page;
 }
@@ -1387,7 +1382,9 @@  static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,
 		if (i->nofault)
 			gup_flags |= FOLL_NOFAULT;
 
-		addr = first_iovec_segment(i, &len, start, maxsize, maxpages);
+		addr = first_iovec_segment(i, &len, start, maxsize);
+		if (len > maxpages * PAGE_SIZE)
+			len = maxpages * PAGE_SIZE;
 		n = DIV_ROUND_UP(len, PAGE_SIZE);
 		if (!*pages) {
 			*pages = get_pages_array(n);
@@ -1403,7 +1400,9 @@  static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,
 		struct page **p;
 		struct page *page;
 
-		page = first_bvec_segment(i, &len, start, maxsize, maxpages);
+		page = first_bvec_segment(i, &len, start, maxsize);
+		if (len > maxpages * PAGE_SIZE)
+			len = maxpages * PAGE_SIZE;
 		n = DIV_ROUND_UP(len, PAGE_SIZE);
 		p = *pages;
 		if (!p) {