KVM Archive on lore.kernel.org
 help / color / Atom feed
From: Vivek Goyal <vgoyal@redhat.com>
To: Eric Ren <ericdotren@gmail.com>
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
	kvm@vger.kernel.org, linux-nvdimm@lists.01.org,
	miklos@szeredi.hu, stefanha@redhat.com, dgilbert@redhat.com,
	swhiteho@redhat.com
Subject: Re: [PATCH v2 26/30] fuse: Add logic to free up a memory range
Date: Mon, 20 May 2019 08:53:55 -0400
Message-ID: <20190520125355.GA28008@redhat.com> (raw)
In-Reply-To: <CAN+Pk99SNKSf+GjSQUUWt_eu1fSjTy_ByUOEQUXHi8zNqXY1zA@mail.gmail.com>

On Sun, May 19, 2019 at 03:48:05PM +0800, Eric Ren wrote:
> Hi,
> 
> @@ -1784,8 +1822,23 @@ static int fuse_iomap_begin(struct inode *inode,
> > loff_t pos, loff_t length,
> >                 if (pos >= i_size_read(inode))
> >                         goto iomap_hole;
> >
> > -               alloc_dmap = alloc_dax_mapping(fc);
> > -               if (!alloc_dmap)
> > +               /* Can't do reclaim in fault path yet due to lock ordering.
> > +                * Read path takes shared inode lock and that's not
> > sufficient
> > +                * for inline range reclaim. Caller needs to drop lock,
> > wait
> > +                * and retry.
> > +                */
> > +               if (flags & IOMAP_FAULT || !(flags & IOMAP_WRITE)) {
> > +                       alloc_dmap = alloc_dax_mapping(fc);
> > +                       if (!alloc_dmap)
> > +                               return -ENOSPC;
> > +               } else {
> > +                       alloc_dmap = alloc_dax_mapping_reclaim(fc, inode);
> >
> 
> alloc_dmap could be NULL as follows:
> 
> alloc_dax_mapping_reclaim
>    -->fuse_dax_reclaim_first_mapping
>              -->fuse_dax_reclaim_first_mapping_locked
>                   --> fuse_dax_interval_tree_iter_first  ==> return NULL
> and
> 
> IS_ERR(NULL) is false, so we may miss that error case.

Hi Eric,

Good catch. I will fix it next version. 

Thanks
Vivek

  parent reply index

Thread overview: 52+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-15 19:26 [PATCH v2 00/30] [RFC] virtio-fs: shared file system for virtual machines Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 01/30] fuse: delete dentry if timeout is zero Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 02/30] fuse: Clear setuid bit even in cache=never path Vivek Goyal
2019-05-20 14:41   ` Miklos Szeredi
2019-05-20 14:44     ` Miklos Szeredi
2019-05-20 20:25       ` Nikolaus Rath
2019-05-21 15:01     ` Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 03/30] fuse: Use default_file_splice_read for direct IO Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 04/30] fuse: export fuse_end_request() Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 05/30] fuse: export fuse_len_args() Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 06/30] fuse: Export fuse_send_init_request() Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 07/30] fuse: export fuse_get_unique() Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 08/30] fuse: extract fuse_fill_super_common() Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 09/30] fuse: add fuse_iqueue_ops callbacks Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 10/30] fuse: Separate fuse device allocation and installation in fuse_conn Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 11/30] virtio_fs: add skeleton virtio_fs.ko module Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 12/30] dax: remove block device dependencies Vivek Goyal
2019-05-16  0:21   ` Dan Williams
2019-05-16 10:07     ` Stefan Hajnoczi
2019-05-16 14:23     ` Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 13/30] dax: Pass dax_dev to dax_writeback_mapping_range() Vivek Goyal
2019-05-15 19:26 ` [PATCH v2 14/30] virtio: Add get_shm_region method Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 15/30] virtio: Implement get_shm_region for PCI transport Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 16/30] virtio: Implement get_shm_region for MMIO transport Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 17/30] fuse, dax: add fuse_conn->dax_dev field Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 18/30] virtio_fs, dax: Set up virtio_fs dax_device Vivek Goyal
2019-07-17 17:27   ` Halil Pasic
2019-07-18  9:04     ` Cornelia Huck
2019-07-18 11:20       ` Halil Pasic
2019-07-18 14:47         ` Cornelia Huck
2019-07-18 13:15     ` Vivek Goyal
2019-07-18 14:30       ` Dan Williams
2019-07-22 10:51         ` Christian Borntraeger
2019-07-22 10:56           ` Dr. David Alan Gilbert
2019-07-22 11:20             ` Christian Borntraeger
2019-07-22 11:43               ` Cornelia Huck
2019-07-22 12:00                 ` Christian Borntraeger
2019-07-22 12:08                   ` David Hildenbrand
2019-07-29 13:20                     ` Stefan Hajnoczi
2019-05-15 19:27 ` [PATCH v2 19/30] fuse: Keep a list of free dax memory ranges Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 20/30] fuse: Introduce setupmapping/removemapping commands Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 21/30] fuse, dax: Implement dax read/write operations Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 22/30] fuse, dax: add DAX mmap support Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 23/30] fuse: Define dax address space operations Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 24/30] fuse, dax: Take ->i_mmap_sem lock during dax page fault Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 25/30] fuse: Maintain a list of busy elements Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 26/30] fuse: Add logic to free up a memory range Vivek Goyal
     [not found]   ` <CAN+Pk99SNKSf+GjSQUUWt_eu1fSjTy_ByUOEQUXHi8zNqXY1zA@mail.gmail.com>
2019-05-20 12:53     ` Vivek Goyal [this message]
2019-05-15 19:27 ` [PATCH v2 27/30] fuse: Release file in process context Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 28/30] fuse: Reschedule dax free work if too many EAGAIN attempts Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 29/30] fuse: Take inode lock for dax inode truncation Vivek Goyal
2019-05-15 19:27 ` [PATCH v2 30/30] virtio-fs: Do not provide abort interface in fusectl Vivek Goyal

Reply instructions:

You may reply publically 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=20190520125355.GA28008@redhat.com \
    --to=vgoyal@redhat.com \
    --cc=dgilbert@redhat.com \
    --cc=ericdotren@gmail.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-nvdimm@lists.01.org \
    --cc=miklos@szeredi.hu \
    --cc=stefanha@redhat.com \
    --cc=swhiteho@redhat.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

KVM Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/kvm/0 kvm/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 kvm kvm/ https://lore.kernel.org/kvm \
		kvm@vger.kernel.org kvm@archiver.kernel.org
	public-inbox-index kvm

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.kvm


AGPL code for this site: git clone https://public-inbox.org/ public-inbox