From: Matthew Wilcox <willy@linux.intel.com>
To: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org,
linux-fsdevel@vger.kernel.org, linux-nvdimm@lists.01.org
Subject: Re: [PATCH] mm: make GUP handle pfn mapping unless FOLL_GET is requested
Date: Wed, 24 Jun 2015 12:40:59 -0400 [thread overview]
Message-ID: <20150624164059.GF1971@linux.intel.com> (raw)
In-Reply-To: <1435141503-100635-1-git-send-email-kirill.shutemov@linux.intel.com>
On Wed, Jun 24, 2015 at 01:25:03PM +0300, Kirill A. Shutemov wrote:
> With DAX, pfn mapping becoming more common. The patch adjusts GUP code
> to cover pfn mapping for cases when we don't need struct page to
> proceed.
>
> To make it possible, let's change follow_page() code to return -EEXIST
> error code if proper page table entry exists, but no corresponding
> struct page. __get_user_page() would ignore the error code and move to
> the next page frame.
>
> The immediate effect of the change is working MAP_POPULATE and mlock()
> on DAX mappings.
>
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> Reviewed-by: Toshi Kani <toshi.kani@hp.com>
> Cc: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Matthew Wilcox <willy@linux.intel.com>
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
WARNING: multiple messages have this Message-ID (diff)
From: Matthew Wilcox <willy@linux.intel.com>
To: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org,
linux-fsdevel@vger.kernel.org, linux-nvdimm@lists.01.org
Subject: Re: [PATCH] mm: make GUP handle pfn mapping unless FOLL_GET is requested
Date: Wed, 24 Jun 2015 12:40:59 -0400 [thread overview]
Message-ID: <20150624164059.GF1971@linux.intel.com> (raw)
In-Reply-To: <1435141503-100635-1-git-send-email-kirill.shutemov@linux.intel.com>
On Wed, Jun 24, 2015 at 01:25:03PM +0300, Kirill A. Shutemov wrote:
> With DAX, pfn mapping becoming more common. The patch adjusts GUP code
> to cover pfn mapping for cases when we don't need struct page to
> proceed.
>
> To make it possible, let's change follow_page() code to return -EEXIST
> error code if proper page table entry exists, but no corresponding
> struct page. __get_user_page() would ignore the error code and move to
> the next page frame.
>
> The immediate effect of the change is working MAP_POPULATE and mlock()
> on DAX mappings.
>
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> Reviewed-by: Toshi Kani <toshi.kani@hp.com>
> Cc: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Matthew Wilcox <willy@linux.intel.com>
WARNING: multiple messages have this Message-ID (diff)
From: Matthew Wilcox <willy@linux.intel.com>
To: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org,
linux-fsdevel@vger.kernel.org, linux-nvdimm@ml01.01.org
Subject: Re: [PATCH] mm: make GUP handle pfn mapping unless FOLL_GET is requested
Date: Wed, 24 Jun 2015 12:40:59 -0400 [thread overview]
Message-ID: <20150624164059.GF1971@linux.intel.com> (raw)
In-Reply-To: <1435141503-100635-1-git-send-email-kirill.shutemov@linux.intel.com>
On Wed, Jun 24, 2015 at 01:25:03PM +0300, Kirill A. Shutemov wrote:
> With DAX, pfn mapping becoming more common. The patch adjusts GUP code
> to cover pfn mapping for cases when we don't need struct page to
> proceed.
>
> To make it possible, let's change follow_page() code to return -EEXIST
> error code if proper page table entry exists, but no corresponding
> struct page. __get_user_page() would ignore the error code and move to
> the next page frame.
>
> The immediate effect of the change is working MAP_POPULATE and mlock()
> on DAX mappings.
>
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> Reviewed-by: Toshi Kani <toshi.kani@hp.com>
> Cc: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Matthew Wilcox <willy@linux.intel.com>
next prev parent reply other threads:[~2015-06-24 16:40 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-24 10:25 [PATCH] mm: make GUP handle pfn mapping unless FOLL_GET is requested Kirill A. Shutemov
2015-06-24 10:25 ` Kirill A. Shutemov
2015-06-24 10:25 ` Kirill A. Shutemov
2015-06-24 16:40 ` Matthew Wilcox [this message]
2015-06-24 16:40 ` Matthew Wilcox
2015-06-24 16:40 ` Matthew Wilcox
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20150624164059.GF1971@linux.intel.com \
--to=willy@linux.intel.com \
--cc=akpm@linux-foundation.org \
--cc=kirill.shutemov@linux.intel.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-nvdimm@lists.01.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.