From: Oleksandr <olekstysh@gmail.com>
To: paul@xen.org
Cc: xen-devel@lists.xenproject.org,
"'Oleksandr Tyshchenko'" <oleksandr_tyshchenko@epam.com>,
"'Andrew Cooper'" <andrew.cooper3@citrix.com>,
"'George Dunlap'" <george.dunlap@citrix.com>,
"'Ian Jackson'" <iwj@xenproject.org>,
"'Jan Beulich'" <jbeulich@suse.com>,
"'Julien Grall'" <julien@xen.org>,
"'Stefano Stabellini'" <sstabellini@kernel.org>,
"'Wei Liu'" <wl@xen.org>,
"'Roger Pau Monné'" <roger.pau@citrix.com>,
"'Tim Deegan'" <tim@xen.org>,
"'Julien Grall'" <julien.grall@arm.com>
Subject: Re: [PATCH V2 02/23] xen/ioreq: Make x86's IOREQ feature common
Date: Tue, 17 Nov 2020 16:47:50 +0200 [thread overview]
Message-ID: <34133df1-bff2-f4df-00a5-674a2af867fc@gmail.com> (raw)
In-Reply-To: <436143ea-609f-f6c3-4952-19fcf410fe8f@gmail.com>
Hi Paul
>
>> The 'legacy' mechanism of mapping magic pages for ioreq servers
>> should remain x86 specific I think that aspect of the code needs to
>> remain behind and not get moved into common code. You could do that
>> in arch specific calls in hvm_ioreq_server_enable/disable() and
>> hvm_get_ioreq_server_info().
> Well, if legacy mechanism is not going to be used for other arch and
> should remain x86 specific, I will try to investigate what should be
> left in x86 code and rework the series.
> As a side note, I am afraid, we won't get a 100% code movement (which
> I managed to achieve here) for the next version of this patch as we
> need arch/x86/hvm/ioreq.c.
I am investigating how to split the code in order to leave the 'legacy'
mechanism x86 specific and have a few questions. Could you please
clarify the following:
1. The split of hvm_ioreq_server_enable/disable() is obvious to me, I
would like to clarify regarding hvm_get_ioreq_server_info().
Is it close to what you had in mind when suggesting the split of
hvm_get_ioreq_server_info() or I just need to abstract
hvm_ioreq_server_map_pages() call only?
(Not completed and non tested)
+/* Called with ioreq_server lock held */
+int arch_ioreq_server_get_info(struct hvm_ioreq_server *s,
+ unsigned long *ioreq_gfn,
+ unsigned long *bufioreq_gfn,
+ evtchn_port_t *bufioreq_port)
+{
+ if ( ioreq_gfn || bufioreq_gfn )
+ {
+ int rc = hvm_ioreq_server_map_pages(s);
+
+ if ( rc )
+ return rc;
+ }
+
+ if ( ioreq_gfn )
+ *ioreq_gfn = gfn_x(s->ioreq.gfn);
+
+ if ( HANDLE_BUFIOREQ(s) )
+ {
+ if ( bufioreq_gfn )
+ *bufioreq_gfn = gfn_x(s->bufioreq.gfn);
+
+ if ( bufioreq_port )
+ *bufioreq_port = s->bufioreq_evtchn;
+ }
+
+ return 0;
+}
+
int hvm_get_ioreq_server_info(struct domain *d, ioservid_t id,
unsigned long *ioreq_gfn,
unsigned long *bufioreq_gfn,
@@ -916,26 +954,7 @@ int hvm_get_ioreq_server_info(struct domain *d,
ioservid_t id,
if ( s->emulator != current->domain )
goto out;
- if ( ioreq_gfn || bufioreq_gfn )
- {
- rc = hvm_ioreq_server_map_pages(s);
- if ( rc )
- goto out;
- }
-
- if ( ioreq_gfn )
- *ioreq_gfn = gfn_x(s->ioreq.gfn);
-
- if ( HANDLE_BUFIOREQ(s) )
- {
- if ( bufioreq_gfn )
- *bufioreq_gfn = gfn_x(s->bufioreq.gfn);
-
- if ( bufioreq_port )
- *bufioreq_port = s->bufioreq_evtchn;
- }
-
- rc = 0;
+ rc = arch_ioreq_server_get_info(s, ioreq_gfn, bufioreq_gfn,
bufioreq_port);
out:
spin_unlock_recursive(&d->arch.hvm.ioreq_server.lock);
2. If I understand the code correctly, besides of the above-mentioned
functions the arch specific calls should be in hvm_ioreq_server_init()
and hvm_ioreq_server_deinit() to actually hide
"hvm_ioreq_server_unmap_pages" usage from the common code. I noticed
that the rollback code in hvm_ioreq_server_init() and the whole
hvm_ioreq_server_deinit() have a lot in common except an extra ASSERT()
and hvm_ioreq_server_free_pages() call in the latter. My question is
could we just replace the rollback code by hvm_ioreq_server_deinit()? I
assume an extra hvm_ioreq_server_free_pages() call wouldn't be an issue
here, but I am not sure what to do with the ASSERT, I expect it to be
triggered at such an early stage (so it probably needs moving out of the
hvm_ioreq_server_deinit() (or dropped?) as well as comment needs
updating). I am asking, because this way we would get *a single* arch
hook here which would be arch_ioreq_server_deinit() and remove code
duplication a bit.
Something close to this.
(Not completed and non tested)
@@ -761,18 +771,17 @@ static int hvm_ioreq_server_init(struct
hvm_ioreq_server *s,
return 0;
fail_add:
- hvm_ioreq_server_remove_all_vcpus(s);
- hvm_ioreq_server_unmap_pages(s);
-
- hvm_ioreq_server_free_rangesets(s);
-
- put_domain(s->emulator);
+ hvm_ioreq_server_deinit(s);
return rc;
}
+void arch_ioreq_server_deinit(struct hvm_ioreq_server *s)
+{
+ hvm_ioreq_server_unmap_pages(s);
+}
+
static void hvm_ioreq_server_deinit(struct hvm_ioreq_server *s)
{
- ASSERT(!s->enabled);
hvm_ioreq_server_remove_all_vcpus(s);
/*
@@ -784,7 +793,7 @@ static void hvm_ioreq_server_deinit(struct
hvm_ioreq_server *s)
* the page_info pointer to NULL, meaning the latter will do
* nothing.
*/
- hvm_ioreq_server_unmap_pages(s);
+ arch_ioreq_server_deinit(s);
hvm_ioreq_server_free_pages(s);
hvm_ioreq_server_free_rangesets(s);
put_domain(s->emulator);
--
Regards,
Oleksandr Tyshchenko
next prev parent reply other threads:[~2020-11-17 14:48 UTC|newest]
Thread overview: 109+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-15 16:44 [PATCH V2 00/23] IOREQ feature (+ virtio-mmio) on Arm Oleksandr Tyshchenko
2020-10-15 16:44 ` [PATCH V2 01/23] x86/ioreq: Prepare IOREQ feature for making it common Oleksandr Tyshchenko
2020-10-20 7:13 ` Paul Durrant
2020-11-04 9:06 ` Oleksandr
2020-11-04 9:59 ` Paul Durrant
2020-11-12 10:58 ` Jan Beulich
2020-11-13 11:09 ` Oleksandr
2020-11-13 11:20 ` Jan Beulich
2020-11-13 12:45 ` Oleksandr
2020-11-13 14:31 ` Jan Beulich
2020-10-15 16:44 ` [PATCH V2 02/23] xen/ioreq: Make x86's IOREQ feature common Oleksandr Tyshchenko
2020-10-20 7:57 ` Paul Durrant
2020-11-10 16:45 ` Oleksandr
2020-11-17 14:47 ` Oleksandr [this message]
2020-11-17 15:29 ` Paul Durrant
2020-11-17 16:29 ` Oleksandr
2020-11-17 19:43 ` Paul Durrant
2020-11-12 11:11 ` Jan Beulich
2020-11-13 13:11 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 03/23] xen/ioreq: Make x86's hvm_ioreq_needs_completion() common Oleksandr Tyshchenko
2020-10-20 7:59 ` Paul Durrant
2020-10-15 16:44 ` [PATCH V2 04/23] xen/ioreq: Provide alias for the handle_mmio() Oleksandr Tyshchenko
2020-10-20 9:14 ` Paul Durrant
2020-10-20 10:05 ` Jan Beulich
2020-10-20 10:38 ` Paul Durrant
2020-11-10 19:44 ` Oleksandr
2020-11-11 7:27 ` Jan Beulich
2020-11-11 8:09 ` Oleksandr
2020-11-11 8:16 ` Jan Beulich
2020-10-15 16:44 ` [PATCH V2 05/23] xen/ioreq: Make x86's hvm_mmio_first(last)_byte() common Oleksandr Tyshchenko
2020-10-20 9:15 ` Paul Durrant
2020-10-15 16:44 ` [PATCH V2 06/23] xen/ioreq: Make x86's hvm_ioreq_(page/vcpu/server) structs common Oleksandr Tyshchenko
2020-10-15 16:44 ` [PATCH V2 07/23] xen/ioreq: Move x86's ioreq_gfn(server) to struct domain Oleksandr Tyshchenko
2020-11-12 11:21 ` Jan Beulich
2020-11-13 14:05 ` Oleksandr
2020-11-18 12:09 ` Oleksandr
2020-11-18 12:29 ` Paul Durrant
2020-10-15 16:44 ` [PATCH V2 08/23] xen/ioreq: Introduce ioreq_params to abstract accesses to arch.hvm.params Oleksandr Tyshchenko
2020-10-20 10:41 ` Paul Durrant
2020-11-10 20:00 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 09/23] xen/dm: Make x86's DM feature common Oleksandr Tyshchenko
2020-11-12 11:32 ` Jan Beulich
2020-11-13 14:28 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 10/23] xen/mm: Make x86's XENMEM_resource_ioreq_server handling common Oleksandr Tyshchenko
2020-11-12 11:40 ` Jan Beulich
2020-11-13 15:00 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 11/23] xen/ioreq: Move x86's io_completion/io_req fields to struct vcpu Oleksandr Tyshchenko
2020-10-20 10:55 ` Paul Durrant
2020-11-10 20:59 ` Oleksandr
2020-11-11 8:04 ` Jan Beulich
2020-11-11 8:14 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 12/23] xen/ioreq: Remove "hvm" prefixes from involved function names Oleksandr Tyshchenko
2020-11-12 11:45 ` Jan Beulich
2020-11-12 12:14 ` Paul Durrant
2020-11-13 15:53 ` Oleksandr
2020-11-23 14:39 ` Oleksandr
2020-11-23 14:56 ` Jan Beulich
2020-11-23 15:47 ` Oleksandr
2020-11-23 15:54 ` Paul Durrant
2020-11-23 16:36 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 13/23] xen/ioreq: Use guest_cmpxchg64() instead of cmpxchg() Oleksandr Tyshchenko
2020-10-15 16:44 ` [PATCH V2 14/23] arm/ioreq: Introduce arch specific bits for IOREQ/DM features Oleksandr Tyshchenko
2020-11-12 11:48 ` Jan Beulich
2020-11-13 15:48 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 15/23] xen/arm: Stick around in leave_hypervisor_to_guest until I/O has completed Oleksandr Tyshchenko
2020-10-15 16:44 ` [PATCH V2 16/23] xen/mm: Handle properly reference in set_foreign_p2m_entry() on Arm Oleksandr Tyshchenko
2020-11-12 12:18 ` Jan Beulich
2020-11-13 17:00 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 17/23] xen/ioreq: Introduce domain_has_ioreq_server() Oleksandr Tyshchenko
2020-10-20 10:51 ` Paul Durrant
2020-11-10 20:53 ` Oleksandr
2020-11-11 8:08 ` Jan Beulich
2020-11-11 8:41 ` Oleksandr
2020-11-11 13:27 ` Jan Beulich
2020-11-11 16:28 ` Paul Durrant
2020-11-11 17:33 ` Oleksandr
2020-11-11 17:31 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 18/23] xen/dm: Introduce xendevicemodel_set_irq_level DM op Oleksandr Tyshchenko
2020-10-15 16:44 ` [PATCH V2 19/23] xen/arm: io: Abstract sign-extension Oleksandr Tyshchenko
2020-10-15 16:44 ` [PATCH V2 20/23] xen/ioreq: Make x86's send_invalidate_req() common Oleksandr Tyshchenko
2020-11-12 11:55 ` Jan Beulich
2020-11-13 16:03 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 21/23] xen/arm: Add mapcache invalidation handling Oleksandr Tyshchenko
2020-10-16 6:29 ` Jan Beulich
2020-10-16 8:41 ` Julien Grall
2020-10-16 8:56 ` Jan Beulich
2020-11-11 0:03 ` Oleksandr
2020-11-11 19:27 ` Julien Grall
2020-11-11 19:42 ` Oleksandr
2020-10-15 16:44 ` [PATCH V2 22/23] libxl: Introduce basic virtio-mmio support on Arm Oleksandr Tyshchenko
2020-10-15 16:44 ` [PATCH V2 23/23] [RFC] libxl: Add support for virtio-disk configuration Oleksandr Tyshchenko
2020-11-09 6:45 ` Wei Chen
2020-11-11 0:53 ` Oleksandr
2020-11-11 4:28 ` Wei Chen
2020-11-13 17:38 ` Oleksandr
2020-10-29 7:41 ` [PATCH V2 00/23] IOREQ feature (+ virtio-mmio) on Arm Masami Hiramatsu
2020-10-29 18:48 ` Oleksandr Tyshchenko
2020-10-29 19:53 ` Stefano Stabellini
2020-10-29 21:13 ` Oleksandr Tyshchenko
2020-10-29 21:34 ` Stefano Stabellini
2020-10-30 11:34 ` Masami Hiramatsu
2020-10-31 21:10 ` Oleksandr Tyshchenko
2020-11-02 7:23 ` Wei Chen
2020-11-02 18:05 ` Oleksandr
2020-11-03 14:30 ` Masami Hiramatsu
2020-11-03 21:09 ` Oleksandr
2020-10-29 20:03 ` Alex Bennée
2020-10-29 20:10 ` Stefano Stabellini
2020-10-29 22:06 ` Oleksandr Tyshchenko
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=34133df1-bff2-f4df-00a5-674a2af867fc@gmail.com \
--to=olekstysh@gmail.com \
--cc=andrew.cooper3@citrix.com \
--cc=george.dunlap@citrix.com \
--cc=iwj@xenproject.org \
--cc=jbeulich@suse.com \
--cc=julien.grall@arm.com \
--cc=julien@xen.org \
--cc=oleksandr_tyshchenko@epam.com \
--cc=paul@xen.org \
--cc=roger.pau@citrix.com \
--cc=sstabellini@kernel.org \
--cc=tim@xen.org \
--cc=wl@xen.org \
--cc=xen-devel@lists.xenproject.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 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).