From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
To: Stefan Hajnoczi <stefanha@redhat.com>
Cc: virtio-fs@redhat.com, qemu-devel@nongnu.org, vgoyal@redhat.com,
groug@kaod.org
Subject: Re: [PATCH v3 18/26] DAX/unmap: virtiofsd: Add VHOST_USER_SLAVE_FS_IO
Date: Thu, 27 May 2021 18:44:41 +0100 [thread overview]
Message-ID: <YK/aiXx52Oe2HV4C@work-vm> (raw)
In-Reply-To: <YJQHRwkUhXT+PLtT@stefanha-x1.localdomain>
* Stefan Hajnoczi (stefanha@redhat.com) wrote:
> On Wed, Apr 28, 2021 at 12:00:52PM +0100, Dr. David Alan Gilbert (git) wrote:
> > @@ -220,6 +222,99 @@ uint64_t vhost_user_fs_slave_unmap(struct vhost_dev *dev, int message_size,
> > return (uint64_t)res;
> > }
> >
> > +uint64_t vhost_user_fs_slave_io(struct vhost_dev *dev, int message_size,
> > + VhostUserFSSlaveMsg *sm, int fd)
> > +{
> > + VHostUserFS *fs = (VHostUserFS *)object_dynamic_cast(OBJECT(dev->vdev),
> > + TYPE_VHOST_USER_FS);
> > + if (!fs) {
> > + error_report("%s: Bad fs ptr", __func__);
> > + return (uint64_t)-1;
> > + }
> > + if (!check_slave_message_entries(sm, message_size)) {
> > + return (uint64_t)-1;
> > + }
>
> These early error returns don't close(fd).
(as per followup, we don't need it and it's removed)
> > +
> > + unsigned int i;
> > + int res = 0;
> > + size_t done = 0;
> > +
> > + if (fd < 0) {
> > + error_report("Bad fd for io");
> > + return (uint64_t)-1;
> > + }
> > +
> > + for (i = 0; i < sm->count && !res; i++) {
> > + VhostUserFSSlaveMsgEntry *e = &sm->entries[i];
> > + if (e->len == 0) {
> > + continue;
> > + }
> > +
> > + size_t len = e->len;
> > + uint64_t fd_offset = e->fd_offset;
> > + hwaddr gpa = e->c_offset;
> > +
> > + while (len && !res) {
> > + hwaddr xlat, xlat_len;
> > + bool is_write = e->flags & VHOST_USER_FS_FLAG_MAP_W;
> > + MemoryRegion *mr = address_space_translate(dev->vdev->dma_as, gpa,
> > + &xlat, &xlat_len,
> > + is_write,
> > + MEMTXATTRS_UNSPECIFIED);
> > + if (!mr || !xlat_len) {
> > + error_report("No guest region found for 0x%" HWADDR_PRIx, gpa);
> > + res = -EFAULT;
> > + break;
> > + }
> > +
> > + trace_vhost_user_fs_slave_io_loop(mr->name,
> > + (uint64_t)xlat,
> > + memory_region_is_ram(mr),
> > + memory_region_is_romd(mr),
> > + (size_t)xlat_len);
> > +
> > + void *hostptr = qemu_map_ram_ptr(mr->ram_block,
> > + xlat);
> > + ssize_t transferred;
>
> What happens when the MemoryRegion is not backed by RAM?
I've added a check for mr->ramblock being non-null that I think covers
it.
> > + if (e->flags & VHOST_USER_FS_FLAG_MAP_R) {
> > + /* Read from file into RAM */
> > + if (mr->readonly) {
> > + res = -EFAULT;
> > + break;
> > + }
> > + transferred = pread(fd, hostptr, xlat_len, fd_offset);
> > + } else if (e->flags & VHOST_USER_FS_FLAG_MAP_W) {
> > + /* Write into file from RAM */
> > + transferred = pwrite(fd, hostptr, xlat_len, fd_offset);
> > + } else {
> > + transferred = EINVAL;
>
> I don't see how this is handled below by the error checking code. Should
> this be:
>
> errno = EINVAL;
> transferred = -1;
>
> ?
Thanks; I've gone with res = - EINVAL; break;
Dave
>
> > + }
> > +
> > + trace_vhost_user_fs_slave_io_loop_res(transferred);
> > + if (transferred < 0) {
> > + res = -errno;
> > + break;
> > + }
> > + if (!transferred) {
> > + /* EOF */
> > + break;
> > + }
> > +
> > + done += transferred;
> > + fd_offset += transferred;
> > + gpa += transferred;
> > + len -= transferred;
> > + }
> > + }
> > + close(fd);
> > +
> > + trace_vhost_user_fs_slave_io_exit(res, done);
> > + if (res < 0) {
> > + return (uint64_t)res;
> > + }
> > + return (uint64_t)done;
> > +}
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
next prev parent reply other threads:[~2021-05-27 17:45 UTC|newest]
Thread overview: 66+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-28 11:00 [PATCH v3 00/26] virtiofs dax patches Dr. David Alan Gilbert (git)
2021-04-28 11:00 ` [PATCH v3 01/26] virtiofs: Fixup printf args Dr. David Alan Gilbert (git)
2021-05-04 14:54 ` Stefan Hajnoczi
2021-05-05 11:06 ` Dr. David Alan Gilbert
2021-05-06 15:56 ` Dr. David Alan Gilbert
2021-04-28 11:00 ` [PATCH v3 02/26] virtiofsd: Don't assume header layout Dr. David Alan Gilbert (git)
2021-05-04 15:12 ` Stefan Hajnoczi
2021-05-06 15:56 ` Dr. David Alan Gilbert
2021-04-28 11:00 ` [PATCH v3 03/26] DAX: vhost-user: Rework slave return values Dr. David Alan Gilbert (git)
2021-05-04 15:23 ` Stefan Hajnoczi
2021-05-27 15:59 ` Dr. David Alan Gilbert
2021-04-28 11:00 ` [PATCH v3 04/26] DAX: libvhost-user: Route slave message payload Dr. David Alan Gilbert (git)
2021-05-04 15:26 ` Stefan Hajnoczi
2021-04-28 11:00 ` [PATCH v3 05/26] DAX: libvhost-user: Allow popping a queue element with bad pointers Dr. David Alan Gilbert (git)
2021-04-28 11:00 ` [PATCH v3 06/26] DAX subprojects/libvhost-user: Add virtio-fs slave types Dr. David Alan Gilbert (git)
2021-04-29 15:48 ` Dr. David Alan Gilbert
2021-04-28 11:00 ` [PATCH v3 07/26] DAX: virtio: Add shared memory capability Dr. David Alan Gilbert (git)
2021-04-28 11:00 ` [PATCH v3 08/26] DAX: virtio-fs: Add cache BAR Dr. David Alan Gilbert (git)
2021-05-05 12:12 ` Stefan Hajnoczi
2021-05-05 18:59 ` Dr. David Alan Gilbert
2021-04-28 11:00 ` [PATCH v3 09/26] DAX: virtio-fs: Add vhost-user slave commands for mapping Dr. David Alan Gilbert (git)
2021-05-05 14:15 ` Stefan Hajnoczi
2021-05-27 16:57 ` Dr. David Alan Gilbert
2021-04-28 11:00 ` [PATCH v3 10/26] DAX: virtio-fs: Fill in " Dr. David Alan Gilbert (git)
2021-05-05 16:43 ` Stefan Hajnoczi
2021-04-28 11:00 ` [PATCH v3 11/26] DAX: virtiofsd Add cache accessor functions Dr. David Alan Gilbert (git)
2021-04-28 11:00 ` [PATCH v3 12/26] DAX: virtiofsd: Add setup/remove mappings fuse commands Dr. David Alan Gilbert (git)
2021-05-06 15:02 ` Stefan Hajnoczi
2021-04-28 11:00 ` [PATCH v3 13/26] DAX: virtiofsd: Add setup/remove mapping handlers to passthrough_ll Dr. David Alan Gilbert (git)
2021-04-28 11:00 ` [PATCH v3 14/26] DAX: virtiofsd: Wire up passthrough_ll's lo_setupmapping Dr. David Alan Gilbert (git)
2021-04-28 11:00 ` [PATCH v3 15/26] DAX: virtiofsd: Make lo_removemapping() work Dr. David Alan Gilbert (git)
2021-04-28 11:00 ` [PATCH v3 16/26] DAX: virtiofsd: route se down to destroy method Dr. David Alan Gilbert (git)
2021-04-28 11:00 ` [PATCH v3 17/26] DAX: virtiofsd: Perform an unmap on destroy Dr. David Alan Gilbert (git)
2021-04-28 11:00 ` [PATCH v3 18/26] DAX/unmap: virtiofsd: Add VHOST_USER_SLAVE_FS_IO Dr. David Alan Gilbert (git)
2021-05-06 15:12 ` Stefan Hajnoczi
2021-05-27 17:44 ` Dr. David Alan Gilbert [this message]
2021-05-06 15:16 ` Stefan Hajnoczi
2021-05-27 17:31 ` Dr. David Alan Gilbert
2021-04-28 11:00 ` [PATCH v3 19/26] DAX/unmap virtiofsd: Add wrappers for VHOST_USER_SLAVE_FS_IO Dr. David Alan Gilbert (git)
2021-04-28 12:53 ` Dr. David Alan Gilbert
2021-04-28 11:00 ` [PATCH v3 20/26] DAX/unmap virtiofsd: Parse unmappable elements Dr. David Alan Gilbert (git)
2021-05-06 15:23 ` Stefan Hajnoczi
2021-05-27 17:56 ` Dr. David Alan Gilbert
2021-04-28 11:00 ` [PATCH v3 21/26] DAX/unmap virtiofsd: Route unmappable reads Dr. David Alan Gilbert (git)
2021-05-06 15:27 ` Stefan Hajnoczi
2021-04-28 11:00 ` [PATCH v3 22/26] DAX/unmap virtiofsd: route unmappable write to slave command Dr. David Alan Gilbert (git)
2021-05-06 15:28 ` Stefan Hajnoczi
2021-04-28 11:00 ` [PATCH v3 23/26] DAX:virtiofsd: implement FUSE_INIT map_alignment field Dr. David Alan Gilbert (git)
2021-04-28 11:00 ` [PATCH v3 24/26] vhost-user-fs: Extend VhostUserFSSlaveMsg to pass additional info Dr. David Alan Gilbert (git)
2021-05-06 15:31 ` Stefan Hajnoczi
2021-05-06 15:32 ` Stefan Hajnoczi
2021-04-28 11:00 ` [PATCH v3 25/26] vhost-user-fs: Implement drop CAP_FSETID functionality Dr. David Alan Gilbert (git)
2021-04-28 11:01 ` [PATCH v3 26/26] virtiofsd: Ask qemu to drop CAP_FSETID if client asked for it Dr. David Alan Gilbert (git)
2021-05-06 15:37 ` Stefan Hajnoczi
2021-05-06 16:02 ` Vivek Goyal
2021-05-10 9:05 ` Stefan Hajnoczi
2021-05-10 15:23 ` Vivek Goyal
2021-05-10 15:32 ` Stefan Hajnoczi
2021-05-27 19:09 ` Dr. David Alan Gilbert
2021-06-10 15:29 ` Dr. David Alan Gilbert
2021-06-10 16:23 ` Stefan Hajnoczi
2021-06-16 12:36 ` Dr. David Alan Gilbert
2021-06-16 15:29 ` Stefan Hajnoczi
2021-06-16 18:35 ` Dr. David Alan Gilbert
2021-04-28 11:27 ` [PATCH v3 00/26] virtiofs dax patches no-reply
2021-05-06 15:37 ` Stefan Hajnoczi
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=YK/aiXx52Oe2HV4C@work-vm \
--to=dgilbert@redhat.com \
--cc=groug@kaod.org \
--cc=qemu-devel@nongnu.org \
--cc=stefanha@redhat.com \
--cc=vgoyal@redhat.com \
--cc=virtio-fs@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
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 read-only IMAP folder(s) and NNTP newsgroup(s).