Add iov_iter_get_pages_flags() and iov_iter_get_pages_alloc_flags()
which take a flags argument that is passed to get_user_pages_fast().
This is so that FOLL_PCI_P2PDMA can be passed when appropriate.
Signed-off-by: Logan Gunthorpe <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
---
include/linux/uio.h | 6 ++++++
lib/iov_iter.c | 32 ++++++++++++++++++++++++--------
2 files changed, 30 insertions(+), 8 deletions(-)
diff --git a/include/linux/uio.h b/include/linux/uio.h
index 2e3134b14ffd..9ede533ce64c 100644
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -247,8 +247,14 @@ void iov_iter_pipe(struct iov_iter *i, unsigned int direction, struct pipe_inode
void iov_iter_discard(struct iov_iter *i, unsigned int direction, size_t count);
void iov_iter_xarray(struct iov_iter *i, unsigned int direction, struct xarray *xarray,
loff_t start, size_t count);
+ssize_t iov_iter_get_pages(struct iov_iter *i, struct page **pages,
+ size_t maxsize, unsigned maxpages, size_t *start,
+ unsigned gup_flags);
ssize_t iov_iter_get_pages2(struct iov_iter *i, struct page **pages,
size_t maxsize, unsigned maxpages, size_t *start);
+ssize_t iov_iter_get_pages_alloc(struct iov_iter *i,
+ struct page ***pages, size_t maxsize, size_t *start,
+ unsigned gup_flags);
ssize_t iov_iter_get_pages_alloc2(struct iov_iter *i, struct page ***pages,
size_t maxsize, size_t *start);
int iov_iter_npages(const struct iov_iter *i, int maxpages);
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index c3ca28ca68a6..53efad017f3c 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -1430,7 +1430,8 @@ static struct page *first_bvec_segment(const struct iov_iter *i,
static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,
struct page ***pages, size_t maxsize,
- unsigned int maxpages, size_t *start)
+ unsigned int maxpages, size_t *start,
+ unsigned int gup_flags)
{
unsigned int n;
@@ -1442,7 +1443,6 @@ static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,
maxsize = MAX_RW_COUNT;
if (likely(user_backed_iter(i))) {
- unsigned int gup_flags = 0;
unsigned long addr;
int res;
@@ -1492,33 +1492,49 @@ static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,
return -EFAULT;
}
-ssize_t iov_iter_get_pages2(struct iov_iter *i,
+ssize_t iov_iter_get_pages(struct iov_iter *i,
struct page **pages, size_t maxsize, unsigned maxpages,
- size_t *start)
+ size_t *start, unsigned gup_flags)
{
if (!maxpages)
return 0;
BUG_ON(!pages);
- return __iov_iter_get_pages_alloc(i, &pages, maxsize, maxpages, start);
+ return __iov_iter_get_pages_alloc(i, &pages, maxsize, maxpages,
+ start, gup_flags);
+}
+EXPORT_SYMBOL_GPL(iov_iter_get_pages);
+
+ssize_t iov_iter_get_pages2(struct iov_iter *i, struct page **pages,
+ size_t maxsize, unsigned maxpages, size_t *start)
+{
+ return iov_iter_get_pages(i, pages, maxsize, maxpages, start, 0);
}
EXPORT_SYMBOL(iov_iter_get_pages2);
-ssize_t iov_iter_get_pages_alloc2(struct iov_iter *i,
+ssize_t iov_iter_get_pages_alloc(struct iov_iter *i,
struct page ***pages, size_t maxsize,
- size_t *start)
+ size_t *start, unsigned gup_flags)
{
ssize_t len;
*pages = NULL;
- len = __iov_iter_get_pages_alloc(i, pages, maxsize, ~0U, start);
+ len = __iov_iter_get_pages_alloc(i, pages, maxsize, ~0U, start,
+ gup_flags);
if (len <= 0) {
kvfree(*pages);
*pages = NULL;
}
return len;
}
+EXPORT_SYMBOL_GPL(iov_iter_get_pages_alloc);
+
+ssize_t iov_iter_get_pages_alloc2(struct iov_iter *i,
+ struct page ***pages, size_t maxsize, size_t *start)
+{
+ return iov_iter_get_pages_alloc(i, pages, maxsize, start, 0);
+}
EXPORT_SYMBOL(iov_iter_get_pages_alloc2);
size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum,
--
2.30.2
On 10/21/22 10:41, Logan Gunthorpe wrote:
> Add iov_iter_get_pages_flags() and iov_iter_get_pages_alloc_flags()
> which take a flags argument that is passed to get_user_pages_fast().
>
> This is so that FOLL_PCI_P2PDMA can be passed when appropriate.
>
> Signed-off-by: Logan Gunthorpe <[email protected]>
> Reviewed-by: Christoph Hellwig <[email protected]>
> ---
> include/linux/uio.h | 6 ++++++
> lib/iov_iter.c | 32 ++++++++++++++++++++++++--------
> 2 files changed, 30 insertions(+), 8 deletions(-)
>
> diff --git a/include/linux/uio.h b/include/linux/uio.h
> index 2e3134b14ffd..9ede533ce64c 100644
> --- a/include/linux/uio.h
> +++ b/include/linux/uio.h
> @@ -247,8 +247,14 @@ void iov_iter_pipe(struct iov_iter *i, unsigned int direction, struct pipe_inode
> void iov_iter_discard(struct iov_iter *i, unsigned int direction, size_t count);
> void iov_iter_xarray(struct iov_iter *i, unsigned int direction, struct xarray *xarray,
> loff_t start, size_t count);
> +ssize_t iov_iter_get_pages(struct iov_iter *i, struct page **pages,
> + size_t maxsize, unsigned maxpages, size_t *start,
> + unsigned gup_flags);
> ssize_t iov_iter_get_pages2(struct iov_iter *i, struct page **pages,
> size_t maxsize, unsigned maxpages, size_t *start);
> +ssize_t iov_iter_get_pages_alloc(struct iov_iter *i,
> + struct page ***pages, size_t maxsize, size_t *start,
> + unsigned gup_flags);
> ssize_t iov_iter_get_pages_alloc2(struct iov_iter *i, struct page ***pages,
> size_t maxsize, size_t *start);
> int iov_iter_npages(const struct iov_iter *i, int maxpages);
> diff --git a/lib/iov_iter.c b/lib/iov_iter.c
> index c3ca28ca68a6..53efad017f3c 100644
> --- a/lib/iov_iter.c
> +++ b/lib/iov_iter.c
> @@ -1430,7 +1430,8 @@ static struct page *first_bvec_segment(const struct iov_iter *i,
>
> static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,
> struct page ***pages, size_t maxsize,
> - unsigned int maxpages, size_t *start)
> + unsigned int maxpages, size_t *start,
> + unsigned int gup_flags)
> {
> unsigned int n;
>
> @@ -1442,7 +1443,6 @@ static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,
> maxsize = MAX_RW_COUNT;
>
> if (likely(user_backed_iter(i))) {
> - unsigned int gup_flags = 0;
> unsigned long addr;
> int res;
>
> @@ -1492,33 +1492,49 @@ static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,
> return -EFAULT;
> }
>
> -ssize_t iov_iter_get_pages2(struct iov_iter *i,
> +ssize_t iov_iter_get_pages(struct iov_iter *i,
> struct page **pages, size_t maxsize, unsigned maxpages,
> - size_t *start)
> + size_t *start, unsigned gup_flags)
> {
> if (!maxpages)
> return 0;
> BUG_ON(!pages);
>
> - return __iov_iter_get_pages_alloc(i, &pages, maxsize, maxpages, start);
> + return __iov_iter_get_pages_alloc(i, &pages, maxsize, maxpages,
> + start, gup_flags);
> +}
> +EXPORT_SYMBOL_GPL(iov_iter_get_pages);
> +
> +ssize_t iov_iter_get_pages2(struct iov_iter *i, struct page **pages,
> + size_t maxsize, unsigned maxpages, size_t *start)
> +{
> + return iov_iter_get_pages(i, pages, maxsize, maxpages, start, 0);
> }
> EXPORT_SYMBOL(iov_iter_get_pages2);
>
> -ssize_t iov_iter_get_pages_alloc2(struct iov_iter *i,
> +ssize_t iov_iter_get_pages_alloc(struct iov_iter *i,
> struct page ***pages, size_t maxsize,
> - size_t *start)
> + size_t *start, unsigned gup_flags)
> {
> ssize_t len;
>
> *pages = NULL;
>
> - len = __iov_iter_get_pages_alloc(i, pages, maxsize, ~0U, start);
> + len = __iov_iter_get_pages_alloc(i, pages, maxsize, ~0U, start,
> + gup_flags);
> if (len <= 0) {
> kvfree(*pages);
> *pages = NULL;
> }
> return len;
> }
> +EXPORT_SYMBOL_GPL(iov_iter_get_pages_alloc);
> +
> +ssize_t iov_iter_get_pages_alloc2(struct iov_iter *i,
> + struct page ***pages, size_t maxsize, size_t *start)
> +{
> + return iov_iter_get_pages_alloc(i, pages, maxsize, start, 0);
> +}
> EXPORT_SYMBOL(iov_iter_get_pages_alloc2);
Just one minor question why not make following functions
EXPORT_SYMBOL_GPL() ?
1. iov_iter_get_pages2()
2. iov_iter_get_pages_alloc2()
Reviewed-by: Chaitanya Kukkarni <[email protected]>
-ck
On 2022-10-24 19:14, Chaitanya Kulkarni wrote:
> On 10/21/22 10:41, Logan Gunthorpe wrote:
>> Add iov_iter_get_pages_flags() and iov_iter_get_pages_alloc_flags()
>> which take a flags argument that is passed to get_user_pages_fast().
>>
>> This is so that FOLL_PCI_P2PDMA can be passed when appropriate.
>>
>> Signed-off-by: Logan Gunthorpe <[email protected]>
>> Reviewed-by: Christoph Hellwig <[email protected]>
>> ---
>> include/linux/uio.h | 6 ++++++
>> lib/iov_iter.c | 32 ++++++++++++++++++++++++--------
>> 2 files changed, 30 insertions(+), 8 deletions(-)
>>
>> diff --git a/include/linux/uio.h b/include/linux/uio.h
>> index 2e3134b14ffd..9ede533ce64c 100644
>> --- a/include/linux/uio.h
>> +++ b/include/linux/uio.h
>> @@ -247,8 +247,14 @@ void iov_iter_pipe(struct iov_iter *i, unsigned int direction, struct pipe_inode
>> void iov_iter_discard(struct iov_iter *i, unsigned int direction, size_t count);
>> void iov_iter_xarray(struct iov_iter *i, unsigned int direction, struct xarray *xarray,
>> loff_t start, size_t count);
>> +ssize_t iov_iter_get_pages(struct iov_iter *i, struct page **pages,
>> + size_t maxsize, unsigned maxpages, size_t *start,
>> + unsigned gup_flags);
>> ssize_t iov_iter_get_pages2(struct iov_iter *i, struct page **pages,
>> size_t maxsize, unsigned maxpages, size_t *start);
>> +ssize_t iov_iter_get_pages_alloc(struct iov_iter *i,
>> + struct page ***pages, size_t maxsize, size_t *start,
>> + unsigned gup_flags);
>> ssize_t iov_iter_get_pages_alloc2(struct iov_iter *i, struct page ***pages,
>> size_t maxsize, size_t *start);
>> int iov_iter_npages(const struct iov_iter *i, int maxpages);
>> diff --git a/lib/iov_iter.c b/lib/iov_iter.c
>> index c3ca28ca68a6..53efad017f3c 100644
>> --- a/lib/iov_iter.c
>> +++ b/lib/iov_iter.c
>> @@ -1430,7 +1430,8 @@ static struct page *first_bvec_segment(const struct iov_iter *i,
>>
>> static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,
>> struct page ***pages, size_t maxsize,
>> - unsigned int maxpages, size_t *start)
>> + unsigned int maxpages, size_t *start,
>> + unsigned int gup_flags)
>> {
>> unsigned int n;
>>
>> @@ -1442,7 +1443,6 @@ static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,
>> maxsize = MAX_RW_COUNT;
>>
>> if (likely(user_backed_iter(i))) {
>> - unsigned int gup_flags = 0;
>> unsigned long addr;
>> int res;
>>
>> @@ -1492,33 +1492,49 @@ static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,
>> return -EFAULT;
>> }
>>
>> -ssize_t iov_iter_get_pages2(struct iov_iter *i,
>> +ssize_t iov_iter_get_pages(struct iov_iter *i,
>> struct page **pages, size_t maxsize, unsigned maxpages,
>> - size_t *start)
>> + size_t *start, unsigned gup_flags)
>> {
>> if (!maxpages)
>> return 0;
>> BUG_ON(!pages);
>>
>> - return __iov_iter_get_pages_alloc(i, &pages, maxsize, maxpages, start);
>> + return __iov_iter_get_pages_alloc(i, &pages, maxsize, maxpages,
>> + start, gup_flags);
>> +}
>> +EXPORT_SYMBOL_GPL(iov_iter_get_pages);
>> +
>> +ssize_t iov_iter_get_pages2(struct iov_iter *i, struct page **pages,
>> + size_t maxsize, unsigned maxpages, size_t *start)
>> +{
>> + return iov_iter_get_pages(i, pages, maxsize, maxpages, start, 0);
>> }
>> EXPORT_SYMBOL(iov_iter_get_pages2);
>>
>> -ssize_t iov_iter_get_pages_alloc2(struct iov_iter *i,
>> +ssize_t iov_iter_get_pages_alloc(struct iov_iter *i,
>> struct page ***pages, size_t maxsize,
>> - size_t *start)
>> + size_t *start, unsigned gup_flags)
>> {
>> ssize_t len;
>>
>> *pages = NULL;
>>
>> - len = __iov_iter_get_pages_alloc(i, pages, maxsize, ~0U, start);
>> + len = __iov_iter_get_pages_alloc(i, pages, maxsize, ~0U, start,
>> + gup_flags);
>> if (len <= 0) {
>> kvfree(*pages);
>> *pages = NULL;
>> }
>> return len;
>> }
>> +EXPORT_SYMBOL_GPL(iov_iter_get_pages_alloc);
>> +
>> +ssize_t iov_iter_get_pages_alloc2(struct iov_iter *i,
>> + struct page ***pages, size_t maxsize, size_t *start)
>> +{
>> + return iov_iter_get_pages_alloc(i, pages, maxsize, start, 0);
>> +}
>> EXPORT_SYMBOL(iov_iter_get_pages_alloc2);
> Just one minor question why not make following functions
> EXPORT_SYMBOL_GPL() ?
>
> 1. iov_iter_get_pages2()
> 2. iov_iter_get_pages_alloc2()
They previously were not GPL, so I didn't think that should be changed
in this patch.
Thanks for the review!
Logan
> > Just one minor question why not make following functions
> > EXPORT_SYMBOL_GPL() ?
> >
> > 1. iov_iter_get_pages2()
> > 2. iov_iter_get_pages_alloc2()
>
> They previously were not GPL, so I didn't think that should be changed
> in this patch.
Yes. While they should have been _GPL from the start, rocking that
boat is a bit pointless now. We just need to make sure to do the
right thing for the pinning variants that are going to replace them soon.
On 2022-10-27 01:11, Jay Fang wrote:
> On 2022/10/22 1:41, Logan Gunthorpe wrote:
>> Add iov_iter_get_pages_flags() and iov_iter_get_pages_alloc_flags()
>> which take a flags argument that is passed to get_user_pages_fast().
>>
>> This is so that FOLL_PCI_P2PDMA can be passed when appropriate.
>>
>> Signed-off-by: Logan Gunthorpe <[email protected]>
>> Reviewed-by: Christoph Hellwig <[email protected]>
>> ---
>> include/linux/uio.h | 6 ++++++
>> lib/iov_iter.c | 32 ++++++++++++++++++++++++--------
>> 2 files changed, 30 insertions(+), 8 deletions(-)
>>
>> diff --git a/include/linux/uio.h b/include/linux/uio.h
>> index 2e3134b14ffd..9ede533ce64c 100644
>> --- a/include/linux/uio.h
>> +++ b/include/linux/uio.h
>> @@ -247,8 +247,14 @@ void iov_iter_pipe(struct iov_iter *i, unsigned int direction, struct pipe_inode
>> void iov_iter_discard(struct iov_iter *i, unsigned int direction, size_t count);
>> void iov_iter_xarray(struct iov_iter *i, unsigned int direction, struct xarray *xarray,
>> loff_t start, size_t count);
>> +ssize_t iov_iter_get_pages(struct iov_iter *i, struct page **pages,
>> + size_t maxsize, unsigned maxpages, size_t *start,
>> + unsigned gup_flags);
>> ssize_t iov_iter_get_pages2(struct iov_iter *i, struct page **pages,
>> size_t maxsize, unsigned maxpages, size_t *start);
>> +ssize_t iov_iter_get_pages_alloc(struct iov_iter *i,
>> + struct page ***pages, size_t maxsize, size_t *start,
>> + unsigned gup_flags);
>> ssize_t iov_iter_get_pages_alloc2(struct iov_iter *i, struct page ***pages,
>> size_t maxsize, size_t *start);
>> int iov_iter_npages(const struct iov_iter *i, int maxpages);
>> diff --git a/lib/iov_iter.c b/lib/iov_iter.c
>> index c3ca28ca68a6..53efad017f3c 100644
>> --- a/lib/iov_iter.c
>> +++ b/lib/iov_iter.c
>> @@ -1430,7 +1430,8 @@ static struct page *first_bvec_segment(const struct iov_iter *i,
>>
>> static ssize_t __iov_iter_get_pages_alloc(struct iov_iter *i,
>> struct page ***pages, size_t maxsize,
>> - unsigned int maxpages, size_t *start)
>> + unsigned int maxpages, size_t *start,
>> + unsigned int gup_flags)
>
> Hi,
> found some checkpatch warnings, like this:
> WARNING: Prefer 'unsigned int' to bare use of 'unsigned'
> #50: FILE: lib/iov_iter.c:1497:
> + size_t *start, unsigned gup_flags)
We usually stick with the choices of the nearby code instead of
the warnings of checkpatch.
Thanks,
Logan