From: Boaz Harrosh <boaz@plexistor.com> To: Dave Chinner <david@fromorbit.com>, Matthew Wilcox <matthew.r.wilcox@intel.com>, Andrew Morton <akpm@linux-foundation.org>, "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>, Jan Kara <jack@suse.cz>, Hugh Dickins <hughd@google.com>, Mel Gorman <mgorman@suse.de>, linux-mm@kvack.org, linux-nvdimm <linux-nvdimm@ml01.01.org>, linux-fsdevel <linux-fsdevel@vger.kernel.org>, Eryu Guan <eguan@redhat.com> Subject: [PATCH 0/3 v4] dax: some dax fixes and cleanups Date: Wed, 25 Mar 2015 15:34:25 +0200 [thread overview] Message-ID: <5512B961.8070409@plexistor.com> (raw) Hi [v4] dax: some dax fixes and cleanups * First patch fixed according to Andrew's comments. Thanks Andrew. 1st and 2nd patch can go into current Kernel as they fix something that was merged this release. * Added a new patch to fix up splice in the dax case, and cleanup. This one can wait for 4.1 (Also the first two not that anyone uses dax in production.) * DAX freeze is not fixed yet. As we have more problems then I originally hoped for, as pointed out by Dave. (Just as a referance I'm sending a NO-GOOD additional patch to show what is not good enough to do. Was the RFC of [v3]) * Not re-posting the xfstest Dave please pick this up (It already found bugs in none dax FSs) [v3] dax: Fix mmap-write not updating c/mtime * I'm re-posting the two DAX patches that fix the mmap-write after read problem with DAX. (No changes since [v2]) * I'm also posting a 3rd RFC patch to address what Jan said about fs_freeze and making mapping read-only. Jan Please review and see if this is what you meant. [v2] Jan Kara has pointed out that if we add the sb_start/end_pagefault pair in the new pfn_mkwrite we are then fixing another bug where: A user could start writing to the page while filesystem is frozen. [v1] The main problem is that current mm/memory.c will no call us with page_mkwrite if we do not have an actual page mapping, which is what DAX uses. The solution presented here introduces a new pfn_mkwrite to solve this problem. Please see patch-2 for details. I've been running with this patch for 4 month both HW and VMs with no apparent danger, but see patch-1 I played it safe. I am also posting an xfstest 080 that demonstrate this problem, I believe that also some git operations (can't remember which) suffer from this problem. Actually Eryu Guan found that this test fails on some other FS as well. List of patches: [PATCH 1/3] mm: New pfn_mkwrite same as page_mkwrite for VM_PFNMAP [PATCH 2/3] dax: use pfn_mkwrite to update c/mtime + freeze [PATCH 3/3] dax: Unify ext2/4_{dax,}_file_operations [PATCH] NOTGOOD: dax: dax_prepare_freeze Andrew hi I believe this needs to eventually go through your tree. Please pick it up when you feel it is ready. I believe all 3 are ready and fix real bugs. Matthew hi I would love to have your ACK on these patches? Thanks Boaz
WARNING: multiple messages have this Message-ID (diff)
From: Boaz Harrosh <boaz@plexistor.com> To: Dave Chinner <david@fromorbit.com>, Matthew Wilcox <matthew.r.wilcox@intel.com>, Andrew Morton <akpm@linux-foundation.org>, "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>, Jan Kara <jack@suse.cz>, Hugh Dickins <hughd@google.com>, Mel Gorman <mgorman@suse.de>, linux-mm@kvack.org, linux-nvdimm <linux-nvdimm@ml01.01.org>, linux-fsdevel <linux-fsdevel@vger.kernel.org>, Eryu Guan <eguan@redhat.com> Subject: [PATCH 0/3 v4] dax: some dax fixes and cleanups Date: Wed, 25 Mar 2015 15:34:25 +0200 [thread overview] Message-ID: <5512B961.8070409@plexistor.com> (raw) Hi [v4] dax: some dax fixes and cleanups * First patch fixed according to Andrew's comments. Thanks Andrew. 1st and 2nd patch can go into current Kernel as they fix something that was merged this release. * Added a new patch to fix up splice in the dax case, and cleanup. This one can wait for 4.1 (Also the first two not that anyone uses dax in production.) * DAX freeze is not fixed yet. As we have more problems then I originally hoped for, as pointed out by Dave. (Just as a referance I'm sending a NO-GOOD additional patch to show what is not good enough to do. Was the RFC of [v3]) * Not re-posting the xfstest Dave please pick this up (It already found bugs in none dax FSs) [v3] dax: Fix mmap-write not updating c/mtime * I'm re-posting the two DAX patches that fix the mmap-write after read problem with DAX. (No changes since [v2]) * I'm also posting a 3rd RFC patch to address what Jan said about fs_freeze and making mapping read-only. Jan Please review and see if this is what you meant. [v2] Jan Kara has pointed out that if we add the sb_start/end_pagefault pair in the new pfn_mkwrite we are then fixing another bug where: A user could start writing to the page while filesystem is frozen. [v1] The main problem is that current mm/memory.c will no call us with page_mkwrite if we do not have an actual page mapping, which is what DAX uses. The solution presented here introduces a new pfn_mkwrite to solve this problem. Please see patch-2 for details. I've been running with this patch for 4 month both HW and VMs with no apparent danger, but see patch-1 I played it safe. I am also posting an xfstest 080 that demonstrate this problem, I believe that also some git operations (can't remember which) suffer from this problem. Actually Eryu Guan found that this test fails on some other FS as well. List of patches: [PATCH 1/3] mm: New pfn_mkwrite same as page_mkwrite for VM_PFNMAP [PATCH 2/3] dax: use pfn_mkwrite to update c/mtime + freeze [PATCH 3/3] dax: Unify ext2/4_{dax,}_file_operations [PATCH] NOTGOOD: dax: dax_prepare_freeze Andrew hi I believe this needs to eventually go through your tree. Please pick it up when you feel it is ready. I believe all 3 are ready and fix real bugs. Matthew hi I would love to have your ACK on these patches? Thanks Boaz -- 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 reply other threads:[~2015-03-25 13:34 UTC|newest] Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top 2015-03-25 13:34 Boaz Harrosh [this message] 2015-03-25 13:34 ` [PATCH 0/3 v4] dax: some dax fixes and cleanups Boaz Harrosh 2015-03-25 13:38 ` [PATCH 1/3] mm: New pfn_mkwrite same as page_mkwrite for VM_PFNMAP Boaz Harrosh 2015-03-25 14:34 ` Kirill A. Shutemov 2015-03-26 7:49 ` Boaz Harrosh 2015-03-25 15:08 ` Dave Hansen 2015-03-25 15:13 ` Kirill A. Shutemov 2015-03-25 13:41 ` [PATCH 2/3] dax: pfn_mkwrite update c/mtime + freeze protection Boaz Harrosh 2015-03-25 13:41 ` Boaz Harrosh 2015-03-25 13:44 ` [PATCH 3/3] dax: Unify ext2/4_{dax,}_file_operations Boaz Harrosh 2015-03-25 13:44 ` Boaz Harrosh 2015-03-25 13:47 ` [FIXME] NOT-GOOD: dax: dax_prepare_freeze Boaz Harrosh 2015-03-25 13:47 ` Boaz Harrosh
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=5512B961.8070409@plexistor.com \ --to=boaz@plexistor.com \ --cc=akpm@linux-foundation.org \ --cc=david@fromorbit.com \ --cc=eguan@redhat.com \ --cc=hughd@google.com \ --cc=jack@suse.cz \ --cc=kirill.shutemov@linux.intel.com \ --cc=linux-fsdevel@vger.kernel.org \ --cc=linux-mm@kvack.org \ --cc=linux-nvdimm@ml01.01.org \ --cc=matthew.r.wilcox@intel.com \ --cc=mgorman@suse.de \ /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: linkBe 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.