Re: [PATCH v11 3/9] iov_iter: introduce iov_iter_get_pages_[alloc_]flags()

From: Logan Gunthorpe
Date: Thu Oct 27 2022 - 10:23:19 EST




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 <logang@xxxxxxxxxxxx>
>> Reviewed-by: Christoph Hellwig <hch@xxxxxx>
>> ---
>> 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