From: "Kirill A. Shutemov" <kirill@shutemov.name>
To: Jan Kara <jack@suse.cz>
Cc: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org,
linux-nvdimm@lists.01.org,
Andrew Morton <akpm@linux-foundation.org>,
Ross Zwisler <ross.zwisler@linux.intel.com>,
"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Subject: Re: [PATCH 17/21] mm: Change return values of finish_mkwrite_fault()
Date: Wed, 16 Nov 2016 01:57:11 +0300 [thread overview]
Message-ID: <20161115225711.GQ23021@node> (raw)
In-Reply-To: <1478233517-3571-18-git-send-email-jack@suse.cz>
On Fri, Nov 04, 2016 at 05:25:13AM +0100, Jan Kara wrote:
> Currently finish_mkwrite_fault() returns 0 when PTE got changed before
> we acquired PTE lock and VM_FAULT_WRITE when we succeeded in modifying
> the PTE. This is somewhat confusing since 0 generally means success, it
> is also inconsistent with finish_fault() which returns 0 on success.
> Change finish_mkwrite_fault() to return 0 on success and VM_FAULT_NOPAGE
> when PTE changed. Practically, there should be no behavioral difference
> since we bail out from the fault the same way regardless whether we
> return 0, VM_FAULT_NOPAGE, or VM_FAULT_WRITE. Also note that
> VM_FAULT_WRITE has no effect for shared mappings since the only two
> places that check it - KSM and GUP - care about private mappings only.
> Generally the meaning of VM_FAULT_WRITE for shared mappings is not well
> defined and we should probably clean that up.
>
> Signed-off-by: Jan Kara <jack@suse.cz>
Sounds right.
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
--
Kirill A. Shutemov
--
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>
next prev parent reply other threads:[~2016-11-15 22:57 UTC|newest]
Thread overview: 57+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-04 4:24 [PATCH 0/21 v4 RESEND] dax: Clear dirty bits after flushing caches Jan Kara
2016-11-04 4:24 ` [PATCH 01/21] mm: Join struct fault_env and vm_fault Jan Kara
2016-11-15 21:50 ` Kirill A. Shutemov
2016-11-16 10:51 ` Peter Zijlstra
2016-11-16 11:01 ` Jan Kara
2016-11-16 17:21 ` Peter Zijlstra
2016-11-17 9:07 ` Jan Kara
2016-11-16 11:13 ` Kirill A. Shutemov
2016-11-04 4:24 ` [PATCH 02/21] mm: Use vmf->address instead of of vmf->virtual_address Jan Kara
2016-11-15 21:55 ` Kirill A. Shutemov
2016-11-16 11:05 ` Jan Kara
2016-11-16 11:32 ` Kirill A. Shutemov
2016-11-16 11:55 ` Jan Kara
2016-11-04 4:24 ` [PATCH 03/21] mm: Use pgoff in struct vm_fault instead of passing it separately Jan Kara
2016-11-15 22:01 ` Kirill A. Shutemov
2016-11-04 4:25 ` [PATCH 04/21] mm: Use passed vm_fault structure in __do_fault() Jan Kara
2016-11-15 22:05 ` Kirill A. Shutemov
2016-11-04 4:25 ` [PATCH 05/21] mm: Trim __do_fault() arguments Jan Kara
2016-11-15 22:10 ` Kirill A. Shutemov
2016-11-16 13:12 ` Jan Kara
2016-11-04 4:25 ` [PATCH 06/21] mm: Use passed vm_fault structure for in wp_pfn_shared() Jan Kara
2016-11-15 22:10 ` Kirill A. Shutemov
2016-11-04 4:25 ` [PATCH 07/21] mm: Add orig_pte field into vm_fault Jan Kara
2016-11-15 22:14 ` Kirill A. Shutemov
2016-11-16 20:00 ` Ross Zwisler
2016-11-04 4:25 ` [PATCH 08/21] mm: Allow full handling of COW faults in ->fault handlers Jan Kara
2016-11-15 22:20 ` Kirill A. Shutemov
2016-11-04 4:25 ` [PATCH 09/21] mm: Factor out functionality to finish page faults Jan Kara
2016-11-15 22:21 ` Kirill A. Shutemov
2016-11-04 4:25 ` [PATCH 10/21] mm: Move handling of COW faults into DAX code Jan Kara
2016-11-15 22:22 ` Kirill A. Shutemov
2016-11-16 21:28 ` Ross Zwisler
2016-11-17 9:36 ` Jan Kara
2016-11-04 4:25 ` [PATCH 11/21] mm: Remove unnecessary vma->vm_ops check Jan Kara
2016-11-15 22:28 ` Kirill A. Shutemov
2016-11-16 13:29 ` Jan Kara
2016-11-16 14:27 ` Kirill A. Shutemov
2016-11-16 14:43 ` Jan Kara
2016-11-04 4:25 ` [PATCH 12/21] mm: Factor out common parts of write fault handling Jan Kara
2016-11-15 22:30 ` Kirill A. Shutemov
2016-11-04 4:25 ` [PATCH 13/21] mm: Pass vm_fault structure into do_page_mkwrite() Jan Kara
2016-11-15 22:40 ` Kirill A. Shutemov
2016-11-16 13:34 ` Jan Kara
2016-11-04 4:25 ` [PATCH 14/21] mm: Use vmf->page during WP faults Jan Kara
2016-11-15 22:42 ` Kirill A. Shutemov
2016-11-04 4:25 ` [PATCH 15/21] mm: Move part of wp_page_reuse() into the single call site Jan Kara
2016-11-15 22:44 ` Kirill A. Shutemov
2016-11-04 4:25 ` [PATCH 16/21] mm: Provide helper for finishing mkwrite faults Jan Kara
2016-11-15 22:52 ` Kirill A. Shutemov
2016-11-16 13:39 ` Jan Kara
2016-11-04 4:25 ` [PATCH 17/21] mm: Change return values of finish_mkwrite_fault() Jan Kara
2016-11-15 22:57 ` Kirill A. Shutemov [this message]
2016-11-04 4:25 ` [PATCH 18/21] mm: Export follow_pte() Jan Kara
2016-11-04 4:25 ` [PATCH 19/21] dax: Make cache flushing protected by entry lock Jan Kara
2016-11-04 4:25 ` [PATCH 20/21] dax: Protect PTE modification on WP fault by radix tree " Jan Kara
2016-11-04 4:25 ` [PATCH 21/21] dax: Clear dirty entry tags on cache flush Jan Kara
-- strict thread matches above, loose matches on Subject: below --
2016-11-01 22:36 [PATCH 0/21 v4] dax: Clear dirty bits after flushing caches Jan Kara
2016-11-01 22:36 ` [PATCH 17/21] mm: Change return values of finish_mkwrite_fault() Jan Kara
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=20161115225711.GQ23021@node \
--to=kirill@shutemov.name \
--cc=akpm@linux-foundation.org \
--cc=jack@suse.cz \
--cc=kirill.shutemov@linux.intel.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-nvdimm@lists.01.org \
--cc=ross.zwisler@linux.intel.com \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).