-From bb18514bdcb93d9b2906bfb2a8aa9fd6c2265710 Mon Sep 17 00:00:00 2001
+From 2b6ca0c6087ed51bc8318731713bb3aa83f606db Mon Sep 17 00:00:00 2001
From: Dietmar Maurer <dietmar@proxmox.com>
Date: Tue, 13 Nov 2012 11:11:38 +0100
Subject: [PATCH v3 4/6] introduce new vma archive format
Makefile.objs | 2 +-
blockdev.c | 6 +-
docs/specs/vma_spec.txt | 24 ++
- vma-reader.c | 801 +++++++++++++++++++++++++++++++++++++++++
- vma-writer.c | 914 +++++++++++++++++++++++++++++++++++++++++++++++
- vma.c | 561 +++++++++++++++++++++++++++++
+ vma-reader.c | 801 ++++++++++++++++++++++++++++++++++++++++
+ vma-writer.c | 933 +++++++++++++++++++++++++++++++++++++++++++++++
+ vma.c | 561 ++++++++++++++++++++++++++++
vma.h | 145 ++++++++
- 8 files changed, 2452 insertions(+), 4 deletions(-)
+ 8 files changed, 2471 insertions(+), 4 deletions(-)
create mode 100644 docs/specs/vma_spec.txt
create mode 100644 vma-reader.c
create mode 100644 vma-writer.c
block-obj-$(CONFIG_POSIX) += event_notifier-posix.o aio-posix.o
block-obj-$(CONFIG_WIN32) += event_notifier-win32.o aio-win32.o
diff --git a/blockdev.c b/blockdev.c
-index bd2198e..99f3e02 100644
+index ba28654..a030a13 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -21,6 +21,7 @@
static QTAILQ_HEAD(drivelist, DriveInfo) drives = QTAILQ_HEAD_INITIALIZER(drives);
-@@ -1508,10 +1509,11 @@ char *qmp_backup(const char *backupfile, bool has_format, BackupFormat format,
+@@ -1515,10 +1516,11 @@ char *qmp_backup(const char *backupfile, bool has_format, BackupFormat format,
/* Todo: try to auto-detect format based on file name */
format = has_format ? format : BACKUP_FORMAT_VMA;
+
diff --git a/vma-writer.c b/vma-writer.c
new file mode 100644
-index 0000000..3f5bbd5
+index 0000000..08c4ee3
--- /dev/null
+++ b/vma-writer.c
-@@ -0,0 +1,914 @@
+@@ -0,0 +1,933 @@
+/*
+ * VMA: Virtual Machine Archive
+ *
+
+typedef struct VmaAIOCB VmaAIOCB;
+struct VmaAIOCB {
-+ VmaWriter *vmaw;
+ unsigned char buffer[VMA_MAX_EXTENT_SIZE];
++ VmaWriter *vmaw;
+ size_t bytes;
+ Coroutine *co;
+};
+ int outbuf_count; /* in VMA_BLOCKS */
+ uint64_t outbuf_block_info[VMA_BLOCKS_PER_EXTENT];
+
-+ VmaAIOCB aiocbs[WRITE_BUFFERS];
++ VmaAIOCB *aiocbs[WRITE_BUFFERS];
+ CoQueue wqueue;
+
+ GChecksum *md5csum;
+ qemu_coroutine_enter(vmaw->co_writer, NULL);
+}
+
++static int vma_co_write_finished(void *opaque)
++{
++ VmaWriter *vmaw = opaque;
++
++ return (vmaw->co_writer != 0);
++}
++
+static ssize_t coroutine_fn
+vma_co_write(VmaWriter *vmaw, const void *buf, size_t bytes)
+{
+
+ DPRINTF("vma_co_write enter %zd\n", bytes);
+
++ assert(vmaw->co_writer == NULL);
++
+ while (done < bytes) {
-+ ret = write(vmaw->fd, buf + done, bytes - done);
++ /* Note: we limit maximal write size - else VM gets slow */
++ ret = write(vmaw->fd, buf + done,
++ (bytes - done) > 4096 ? 4096 : bytes - done);
+ if (ret > 0) {
+ done += ret;
+ DPRINTF("vma_co_write written %zd %zd\n", done, ret);
+
+ vmaw->co_writer = qemu_coroutine_self();
+ qemu_aio_set_fd_handler(vmaw->fd, NULL, vma_co_continue_write,
-+ NULL, vmaw);
++ vma_co_write_finished, vmaw);
+
+ qemu_coroutine_yield();
+ DPRINTF("vma_co_write restart %zd\n", done);
+ }
+ }
+
++ vmaw->co_writer = NULL;
++
+ qemu_co_mutex_unlock(&vmaw->writer_lock);
+
+ DPRINTF("vma_co_write leave %zd\n", done);
+ int i;
+ VmaAIOCB *cb = NULL;
+ for (i = 0; i < WRITE_BUFFERS; i++) {
-+ if (vmaw->aiocbs[i].bytes) {
-+ cb = &vmaw->aiocbs[i];
++ if (vmaw->aiocbs[i]->bytes) {
++ cb = vmaw->aiocbs[i];
+ DPRINTF("FOUND USED AIO BUFFER %d %zd\n", i,
-+ vmaw->aiocbs[i].bytes);
++ vmaw->aiocbs[i]->bytes);
+ break;
+ }
+ }
+ while (!cb) {
+ int i;
+ for (i = 0; i < WRITE_BUFFERS; i++) {
-+ if (!vmaw->aiocbs[i].bytes) {
-+ cb = &vmaw->aiocbs[i];
++ if (!vmaw->aiocbs[i]->bytes) {
++ cb = vmaw->aiocbs[i];
+ break;
+ }
+ }
+ goto err;
+ }
+ vmaw->fd = fileno(vmaw->cmd);
-+ socket_set_nonblock(vmaw->fd);
++
++ /* try to use O_NONBLOCK and O_DIRECT */
++ fcntl(vmaw->fd, F_SETFL, fcntl(vmaw->fd, F_GETFL)|O_NONBLOCK);
++ fcntl(vmaw->fd, F_SETFL, fcntl(vmaw->fd, F_GETFL)|O_DIRECT);
+
+ } else {
+ struct stat st;
+ const char *tmp_id_str;
+
+ if ((stat(filename, &st) == 0) && S_ISFIFO(st.st_mode)) {
-+ oflags = O_NONBLOCK|O_WRONLY;
++ oflags = O_NONBLOCK|O_DIRECT|O_WRONLY;
+ vmaw->fd = qemu_open(filename, oflags, 0644);
+ } else if (strstart(filename, "/dev/fdset/", &tmp_id_str)) {
-+ oflags = O_NONBLOCK|O_WRONLY;
++ oflags = O_NONBLOCK|O_DIRECT|O_WRONLY;
+ vmaw->fd = qemu_open(filename, oflags, 0644);
+ } else if (strstart(filename, "/dev/fdname/", &tmp_id_str)) {
+ vmaw->fd = monitor_get_fd(cur_mon, tmp_id_str, errp);
+ if (vmaw->fd < 0) {
+ goto err;
+ }
++ /* try to use O_NONBLOCK and O_DIRECT */
++ fcntl(vmaw->fd, F_SETFL, fcntl(vmaw->fd, F_GETFL)|O_NONBLOCK);
++ fcntl(vmaw->fd, F_SETFL, fcntl(vmaw->fd, F_GETFL)|O_DIRECT);
+ } else {
-+ oflags = O_NONBLOCK|O_WRONLY|O_CREAT|O_EXCL;
++ oflags = O_NONBLOCK|O_DIRECT|O_WRONLY|O_CREAT|O_EXCL;
+ vmaw->fd = qemu_open(filename, oflags, 0644);
+ }
+
+ }
+ }
+
++ /* we use O_DIRECT, so we need to align IO buffers */
++ int i;
++ for (i = 0; i < WRITE_BUFFERS; i++) {
++ vmaw->aiocbs[i] = qemu_memalign(512, sizeof(VmaAIOCB));
++ memset(vmaw->aiocbs[i], 0, sizeof(VmaAIOCB));
++ }
++
+ vmaw->outbuf_count = 0;
+ vmaw->outbuf_pos = VMA_EXTENT_HEADER_SIZE;
+
+ return vmaw->status;
+}
+
-+static int vma_writer_get_buffer(VmaWriter *vmaw, size_t bytes)
++static int vma_writer_get_buffer(VmaWriter *vmaw)
+{
+ int ret = 0;
+
+ return -1;
+ }
+
-+ /* detect block containing zeroes */
-+ int i;
-+ int bit = 1;
-+ uint16_t mask = 0;
-+ size_t real_size = 0;
-+ for (i = 0; i < 16; i++) {
-+ unsigned char *vmablock = buf + (i*VMA_BLOCK_SIZE);
-+ if (!buffer_is_zero(vmablock, VMA_BLOCK_SIZE)) {
-+ mask |= bit;
-+ real_size += VMA_BLOCK_SIZE;
-+ }
-+ bit = bit << 1;
-+ }
-+
+ /* wait until buffer is available */
-+ if (vma_writer_get_buffer(vmaw, real_size) < 0) {
++ if (vma_writer_get_buffer(vmaw) < 0) {
+ vma_writer_set_error(vmaw, "vma_writer_write: "
+ "vma_writer_get_buffer failed");
+ return -1;
+
+ DPRINTF("VMA WRITE %d %zd\n", dev_id, cluster_num);
+
-+ bit = 1;
++ int i;
++ int bit = 1;
++ uint16_t mask = 0;
+ for (i = 0; i < 16; i++) {
+ unsigned char *vmablock = buf + (i*VMA_BLOCK_SIZE);
-+ if (mask & bit) {
++ if (!buffer_is_zero(vmablock, VMA_BLOCK_SIZE)) {
++ mask |= bit;
+ memcpy(vmaw->outbuf + vmaw->outbuf_pos, vmablock, VMA_BLOCK_SIZE);
+ vmaw->outbuf_pos += VMA_BLOCK_SIZE;
+ } else {
+ g_checksum_free(vmaw->md5csum);
+ }
+
++ for (i = 0; i < WRITE_BUFFERS; i++) {
++ free(vmaw->aiocbs[i]);
++ }
++
+ g_free(vmaw);
+}
+
projects / pve-qemu-kvm.git / blobdiff