From: Stefan Hajnoczi <stefanha@redhat.com>
To: Peter Maydell <peter.maydell@linaro.org>, qemu-devel@nongnu.org
Cc: "Elena Ufimtseva" <elena.ufimtseva@oracle.com>,
"Fam Zheng" <fam@euphon.net>, "Thomas Huth" <thuth@redhat.com>,
"Daniel P. Berrangé" <berrange@redhat.com>,
"Eduardo Habkost" <ehabkost@redhat.com>,
qemu-block@nongnu.org,
"John G Johnson" <john.g.johnson@oracle.com>,
"Denis V. Lunev" <den@openvz.org>,
"Philippe Mathieu-Daudé" <philmd@redhat.com>,
"Michael S. Tsirkin" <mst@redhat.com>,
"Wainer dos Santos Moschetta" <wainersm@redhat.com>,
"Stefan Hajnoczi" <stefanha@redhat.com>,
"Paolo Bonzini" <pbonzini@redhat.com>,
"Igor Mammedov" <imammedo@redhat.com>,
"Jagannathan Raman" <jag.raman@oracle.com>,
"Alex Bennée" <alex.bennee@linaro.org>
Subject: [PULL 09/27] memory: alloc RAM from file at offset
Date: Thu, 4 Feb 2021 09:58:16 +0000 [thread overview]
Message-ID: <20210204095834.345749-10-stefanha@redhat.com> (raw)
In-Reply-To: <20210204095834.345749-1-stefanha@redhat.com>
From: Jagannathan Raman <jag.raman@oracle.com>
Allow RAM MemoryRegion to be created from an offset in a file, instead
of allocating at offset of 0 by default. This is needed to synchronize
RAM between QEMU & remote process.
Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
Signed-off-by: John G Johnson <john.g.johnson@oracle.com>
Signed-off-by: Elena Ufimtseva <elena.ufimtseva@oracle.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 609996697ad8617e3b01df38accc5c208c24d74e.1611938319.git.jag.raman@oracle.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
include/exec/memory.h | 2 ++
include/exec/ram_addr.h | 2 +-
include/qemu/mmap-alloc.h | 4 +++-
backends/hostmem-memfd.c | 2 +-
hw/misc/ivshmem.c | 3 ++-
softmmu/memory.c | 3 ++-
softmmu/physmem.c | 11 +++++++----
util/mmap-alloc.c | 7 ++++---
util/oslib-posix.c | 2 +-
9 files changed, 23 insertions(+), 13 deletions(-)
diff --git a/include/exec/memory.h b/include/exec/memory.h
index 521d9901d7..a9d2b669e8 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -990,6 +990,7 @@ void memory_region_init_ram_from_file(MemoryRegion *mr,
* @size: size of the region.
* @share: %true if memory must be mmaped with the MAP_SHARED flag
* @fd: the fd to mmap.
+ * @offset: offset within the file referenced by fd
* @errp: pointer to Error*, to store an error if it happens.
*
* Note that this function does not do anything to cause the data in the
@@ -1001,6 +1002,7 @@ void memory_region_init_ram_from_fd(MemoryRegion *mr,
uint64_t size,
bool share,
int fd,
+ ram_addr_t offset,
Error **errp);
#endif
diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h
index c6d2ef1d07..d465a483c6 100644
--- a/include/exec/ram_addr.h
+++ b/include/exec/ram_addr.h
@@ -121,7 +121,7 @@ RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
Error **errp);
RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, MemoryRegion *mr,
uint32_t ram_flags, int fd,
- Error **errp);
+ off_t offset, Error **errp);
RAMBlock *qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
MemoryRegion *mr, Error **errp);
diff --git a/include/qemu/mmap-alloc.h b/include/qemu/mmap-alloc.h
index e786266b92..b096ffb7e9 100644
--- a/include/qemu/mmap-alloc.h
+++ b/include/qemu/mmap-alloc.h
@@ -16,6 +16,7 @@ size_t qemu_mempath_getpagesize(const char *mem_path);
* otherwise, the alignment in use will be determined by QEMU.
* @shared: map has RAM_SHARED flag.
* @is_pmem: map has RAM_PMEM flag.
+ * @map_offset: map starts at offset of map_offset from the start of fd
*
* Return:
* On success, return a pointer to the mapped area.
@@ -25,7 +26,8 @@ void *qemu_ram_mmap(int fd,
size_t size,
size_t align,
bool shared,
- bool is_pmem);
+ bool is_pmem,
+ off_t map_offset);
void qemu_ram_munmap(int fd, void *ptr, size_t size);
diff --git a/backends/hostmem-memfd.c b/backends/hostmem-memfd.c
index e5626d4330..69b0ae30bb 100644
--- a/backends/hostmem-memfd.c
+++ b/backends/hostmem-memfd.c
@@ -55,7 +55,7 @@ memfd_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
name = host_memory_backend_get_name(backend);
memory_region_init_ram_from_fd(&backend->mr, OBJECT(backend),
name, backend->size,
- backend->share, fd, errp);
+ backend->share, fd, 0, errp);
g_free(name);
}
diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
index 0505b52c98..603e992a7f 100644
--- a/hw/misc/ivshmem.c
+++ b/hw/misc/ivshmem.c
@@ -495,7 +495,8 @@ static void process_msg_shmem(IVShmemState *s, int fd, Error **errp)
/* mmap the region and map into the BAR2 */
memory_region_init_ram_from_fd(&s->server_bar2, OBJECT(s),
- "ivshmem.bar2", size, true, fd, &local_err);
+ "ivshmem.bar2", size, true, fd, 0,
+ &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
diff --git a/softmmu/memory.c b/softmmu/memory.c
index 333e1ed7b0..fa65f45532 100644
--- a/softmmu/memory.c
+++ b/softmmu/memory.c
@@ -1609,6 +1609,7 @@ void memory_region_init_ram_from_fd(MemoryRegion *mr,
uint64_t size,
bool share,
int fd,
+ ram_addr_t offset,
Error **errp)
{
Error *err = NULL;
@@ -1618,7 +1619,7 @@ void memory_region_init_ram_from_fd(MemoryRegion *mr,
mr->destructor = memory_region_destructor_ram;
mr->ram_block = qemu_ram_alloc_from_fd(size, mr,
share ? RAM_SHARED : 0,
- fd, &err);
+ fd, offset, &err);
if (err) {
mr->size = int128_zero();
object_unparent(OBJECT(mr));
diff --git a/softmmu/physmem.c b/softmmu/physmem.c
index cdcd197656..5303634fc3 100644
--- a/softmmu/physmem.c
+++ b/softmmu/physmem.c
@@ -1461,6 +1461,7 @@ static void *file_ram_alloc(RAMBlock *block,
ram_addr_t memory,
int fd,
bool truncate,
+ off_t offset,
Error **errp)
{
void *area;
@@ -1511,7 +1512,8 @@ static void *file_ram_alloc(RAMBlock *block,
}
area = qemu_ram_mmap(fd, memory, block->mr->align,
- block->flags & RAM_SHARED, block->flags & RAM_PMEM);
+ block->flags & RAM_SHARED, block->flags & RAM_PMEM,
+ offset);
if (area == MAP_FAILED) {
error_setg_errno(errp, errno,
"unable to map backing store for guest RAM");
@@ -1943,7 +1945,7 @@ static void ram_block_add(RAMBlock *new_block, Error **errp, bool shared)
#ifdef CONFIG_POSIX
RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, MemoryRegion *mr,
uint32_t ram_flags, int fd,
- Error **errp)
+ off_t offset, Error **errp)
{
RAMBlock *new_block;
Error *local_err = NULL;
@@ -1996,7 +1998,8 @@ RAMBlock *qemu_ram_alloc_from_fd(ram_addr_t size, MemoryRegion *mr,
new_block->used_length = size;
new_block->max_length = size;
new_block->flags = ram_flags;
- new_block->host = file_ram_alloc(new_block, size, fd, !file_size, errp);
+ new_block->host = file_ram_alloc(new_block, size, fd, !file_size, offset,
+ errp);
if (!new_block->host) {
g_free(new_block);
return NULL;
@@ -2026,7 +2029,7 @@ RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
return NULL;
}
- block = qemu_ram_alloc_from_fd(size, mr, ram_flags, fd, errp);
+ block = qemu_ram_alloc_from_fd(size, mr, ram_flags, fd, 0, errp);
if (!block) {
if (created) {
unlink(mem_path);
diff --git a/util/mmap-alloc.c b/util/mmap-alloc.c
index 27dcccd8ec..ddffa0db4e 100644
--- a/util/mmap-alloc.c
+++ b/util/mmap-alloc.c
@@ -86,7 +86,8 @@ void *qemu_ram_mmap(int fd,
size_t size,
size_t align,
bool shared,
- bool is_pmem)
+ bool is_pmem,
+ off_t map_offset)
{
int flags;
int map_sync_flags = 0;
@@ -147,7 +148,7 @@ void *qemu_ram_mmap(int fd,
offset = QEMU_ALIGN_UP((uintptr_t)guardptr, align) - (uintptr_t)guardptr;
ptr = mmap(guardptr + offset, size, PROT_READ | PROT_WRITE,
- flags | map_sync_flags, fd, 0);
+ flags | map_sync_flags, fd, map_offset);
if (ptr == MAP_FAILED && map_sync_flags) {
if (errno == ENOTSUP) {
@@ -172,7 +173,7 @@ void *qemu_ram_mmap(int fd,
* we will remove these flags to handle compatibility.
*/
ptr = mmap(guardptr + offset, size, PROT_READ | PROT_WRITE,
- flags, fd, 0);
+ flags, fd, map_offset);
}
if (ptr == MAP_FAILED) {
diff --git a/util/oslib-posix.c b/util/oslib-posix.c
index 359c52df12..3041e9f9a6 100644
--- a/util/oslib-posix.c
+++ b/util/oslib-posix.c
@@ -230,7 +230,7 @@ void *qemu_memalign(size_t alignment, size_t size)
void *qemu_anon_ram_alloc(size_t size, uint64_t *alignment, bool shared)
{
size_t align = QEMU_VMALLOC_ALIGN;
- void *ptr = qemu_ram_mmap(-1, size, align, shared, false);
+ void *ptr = qemu_ram_mmap(-1, size, align, shared, false, 0);
if (ptr == MAP_FAILED) {
return NULL;
--
2.29.2
next prev parent reply other threads:[~2021-02-04 10:18 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-04 9:58 [PULL 00/27] Block patches Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 01/27] .github: point Repo Lockdown bot to GitLab repo Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 02/27] gitmodules: use GitLab repos instead of qemu.org Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 03/27] gitlab-ci: remove redundant GitLab repo URL command Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 04/27] docs: update README to use GitLab repo URLs Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 05/27] pc-bios: update mirror URLs to GitLab Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 06/27] get_maintainer: update repo URL " Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 07/27] multi-process: add the concept description to docs/devel/qemu-multiprocess Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 08/27] multi-process: add configure and usage information Stefan Hajnoczi
2021-02-04 9:58 ` Stefan Hajnoczi [this message]
2021-02-04 9:58 ` [PULL 10/27] multi-process: Add config option for multi-process QEMU Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 11/27] multi-process: setup PCI host bridge for remote device Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 12/27] multi-process: setup a machine object for remote device process Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 13/27] io: add qio_channel_writev_full_all helper Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 14/27] io: add qio_channel_readv_full_all_eof & qio_channel_readv_full_all helpers Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 15/27] multi-process: define MPQemuMsg format and transmission functions Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 16/27] multi-process: Initialize message handler in remote device Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 17/27] multi-process: Associate fd of a PCIDevice with its object Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 18/27] multi-process: setup memory manager for remote device Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 19/27] multi-process: introduce proxy object Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 20/27] multi-process: add proxy communication functions Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 21/27] multi-process: Forward PCI config space acceses to the remote process Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 22/27] multi-process: PCI BAR read/write handling for proxy & remote endpoints Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 23/27] multi-process: Synchronize remote memory Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 24/27] multi-process: create IOHUB object to handle irq Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 25/27] multi-process: Retrieve PCI info from remote process Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 26/27] multi-process: perform device reset in the " Stefan Hajnoczi
2021-02-04 9:58 ` [PULL 27/27] docs: fix Parallels Image "dirty bitmap" section Stefan Hajnoczi
2021-02-04 10:02 ` [PULL 00/27] Block patches Peter Maydell
2021-02-04 14:39 ` 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=20210204095834.345749-10-stefanha@redhat.com \
--to=stefanha@redhat.com \
--cc=alex.bennee@linaro.org \
--cc=berrange@redhat.com \
--cc=den@openvz.org \
--cc=ehabkost@redhat.com \
--cc=elena.ufimtseva@oracle.com \
--cc=fam@euphon.net \
--cc=imammedo@redhat.com \
--cc=jag.raman@oracle.com \
--cc=john.g.johnson@oracle.com \
--cc=mst@redhat.com \
--cc=pbonzini@redhat.com \
--cc=peter.maydell@linaro.org \
--cc=philmd@redhat.com \
--cc=qemu-block@nongnu.org \
--cc=qemu-devel@nongnu.org \
--cc=thuth@redhat.com \
--cc=wainersm@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 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.