/* alloc shared memory pages */
void *qemu_vmalloc(size_t size)
{
#if defined(CONFIG_KQEMU)
if (kqemu_allowed)
return kqemu_vmalloc(size);
#endif
#ifndef __ia64__
return qemu_memalign(getpagesize(), size);
#else
return qemu_memalign(65536, size);
#endif
}
static int virtio_blk_handle_write(VirtIOBlockReq *req)
{
if (!req->buffer) {
size_t offset = 0;
int i;
for (i = 1; i < req->elem.out_num; i++)
req->size += req->elem.out_sg[i].iov_len;
req->buffer = qemu_memalign(512, req->size);
if (req->buffer == NULL) {
qemu_free(req);
return -1;
}
/* We copy the data from the SG list to avoid splitting up the request.
This helps performance a lot until we can pass full sg lists as AIO
operations */
for (i = 1; i < req->elem.out_num; i++) {
size_t len;
len = MIN(req->elem.out_sg[i].iov_len,
req->size - offset);
memcpy(req->buffer + offset,
req->elem.out_sg[i].iov_base,
len);
offset += len;
}
}
bdrv_aio_write(req->dev->bs, req->out->sector, req->buffer, req->size / 512,
virtio_blk_rw_complete, req);
return 0;
}
int xenfb_pv_display_init(DisplayState *ds)
{
if (!fb_path || !kbd_path)
return -1;
xs = qemu_mallocz(sizeof(XenFBState));
if (!xs)
return -1;
init_SEMAPHORE(&xs->kbd_sem, 0);
xs->ds = ds;
create_thread("kbdfront", kbdfront_thread, (void*) xs);
ds->data = xs->nonshared_vram = qemu_memalign(PAGE_SIZE, VGA_RAM_SIZE);
memset(ds->data, 0, VGA_RAM_SIZE);
ds->opaque = xs;
ds->depth = 32;
ds->bgr = 0;
ds->width = 640;
ds->height = 400;
ds->linesize = 640 * 4;
ds->dpy_update = xenfb_pv_update;
ds->dpy_resize = xenfb_pv_resize;
ds->dpy_resize_shared = xenfb_pv_resize_shared;
ds->dpy_setdata = xenfb_pv_setdata;
ds->dpy_refresh = xenfb_pv_refresh;
return 0;
}
/* alloc shared memory pages */
void *qemu_vmalloc(size_t size)
{
void *ptr;
ptr = qemu_memalign(getpagesize(), size);
trace_qemu_vmalloc(size, ptr);
return ptr;
}
static XenBlockRequest *xen_block_start_request(XenBlockDataPlane *dataplane)
{
XenBlockRequest *request = NULL;
if (QLIST_EMPTY(&dataplane->freelist)) {
if (dataplane->requests_total >= dataplane->max_requests) {
goto out;
}
/* allocate new struct */
request = g_malloc0(sizeof(*request));
request->dataplane = dataplane;
/*
* We cannot need more pages per requests than this, and since we
* re-use requests, allocate the memory once here. It will be freed
* xen_block_dataplane_destroy() when the request list is freed.
*/
request->buf = qemu_memalign(XC_PAGE_SIZE,
BLKIF_MAX_SEGMENTS_PER_REQUEST *
XC_PAGE_SIZE);
dataplane->requests_total++;
qemu_iovec_init(&request->v, 1);
} else {
/* get one from freelist */
request = QLIST_FIRST(&dataplane->freelist);
QLIST_REMOVE(request, list);
}
QLIST_INSERT_HEAD(&dataplane->inflight, request, list);
dataplane->requests_inflight++;
out:
return request;
}
/* alloc shared memory pages */
void *qemu_vmalloc(size_t size)
{
#if defined(CONFIG_KQEMU)
if (kqemu_allowed)
return kqemu_vmalloc(size);
#endif
return qemu_memalign(getpagesize(), size);
}
static void virtio_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIOBlock *s = to_virtio_blk(vdev);
VirtIOBlockReq *req;
while ((req = virtio_blk_get_request(s))) {
int i;
if (req->elem.out_num < 1 || req->elem.in_num < 1) {
fprintf(stderr, "virtio-blk missing headers\n");
exit(1);
}
if (req->elem.out_sg[0].iov_len < sizeof(*req->out) ||
req->elem.in_sg[req->elem.in_num - 1].iov_len < sizeof(*req->in)) {
fprintf(stderr, "virtio-blk header not in correct element\n");
exit(1);
}
req->out = (void *)req->elem.out_sg[0].iov_base;
req->in = (void *)req->elem.in_sg[req->elem.in_num - 1].iov_base;
if (req->out->type & VIRTIO_BLK_T_SCSI_CMD) {
unsigned int len = sizeof(*req->in);
req->in->status = VIRTIO_BLK_S_UNSUPP;
virtqueue_push(vq, &req->elem, len);
virtio_notify(vdev, vq);
qemu_free(req);
} else if (req->out->type & VIRTIO_BLK_T_OUT) {
if (virtio_blk_handle_write(req) < 0)
break;
} else {
for (i = 0; i < req->elem.in_num - 1; i++)
req->size += req->elem.in_sg[i].iov_len;
req->buffer = qemu_memalign(512, req->size);
if (req->buffer == NULL) {
qemu_free(req);
break;
}
bdrv_aio_read(s->bs, req->out->sector,
req->buffer,
req->size / 512,
virtio_blk_rw_complete,
req);
}
}
/*
* FIXME: Want to check for completions before returning to guest mode,
* so cached reads and writes are reported as quickly as possible. But
* that should be done in the generic block layer.
*/
}
static void *qemu_io_alloc(size_t len, int pattern)
{
void *buf;
if (misalign)
len += MISALIGN_OFFSET;
buf = qemu_memalign(512, len);
memset(buf, pattern, len);
if (misalign)
buf += MISALIGN_OFFSET;
return buf;
}
static int raw_open(BlockDriverState *bs, const char *filename, int flags)
{
BDRVRawState *s = bs->opaque;
int fd, open_flags, ret;
posix_aio_init();
s->lseek_err_cnt = 0;
open_flags = O_BINARY;
if ((flags & BDRV_O_ACCESS) == O_RDWR) {
open_flags |= O_RDWR;
} else {
open_flags |= O_RDONLY;
bs->read_only = 1;
}
if (flags & BDRV_O_CREAT)
open_flags |= O_CREAT | O_TRUNC;
/* Use O_DSYNC for write-through caching, no flags for write-back caching,
* and O_DIRECT for no caching. */
if ((flags & BDRV_O_NOCACHE))
open_flags |= O_DIRECT;
else if (!(flags & BDRV_O_CACHE_WB))
open_flags |= O_DSYNC;
s->type = FTYPE_FILE;
fd = open(filename, open_flags, 0644);
if (fd < 0) {
ret = -errno;
if (ret == -EROFS)
ret = -EACCES;
return ret;
}
s->fd = fd;
s->aligned_buf = NULL;
if ((flags & BDRV_O_NOCACHE)) {
s->aligned_buf = qemu_memalign(512, ALIGNED_BUFFER_SIZE);
if (s->aligned_buf == NULL) {
ret = -errno;
close(fd);
return ret;
}
}
return 0;
}
/* alloc shared memory pages */
void *qemu_vmalloc(size_t size)
{
void *ptr;
size_t align = QEMU_VMALLOC_ALIGN;
#if defined(CONFIG_VALGRIND)
if (running_on_valgrind < 0) {
/* First call, test whether we are running on Valgrind.
This is a substitute for RUNNING_ON_VALGRIND from valgrind.h. */
const char *ld = getenv("LD_PRELOAD");
running_on_valgrind = (ld != NULL && strstr(ld, "vgpreload"));
}
#endif
if (size < align || running_on_valgrind) {
align = getpagesize();
}
ptr = qemu_memalign(align, size);
trace_qemu_vmalloc(size, ptr);
return ptr;
}
/* alloc shared memory pages */
void *qemu_vmalloc(size_t size)
{
return qemu_memalign(getpagesize(), size);
}
static int raw_open_common(BlockDriverState *bs, const char *filename,
int bdrv_flags, int open_flags)
{
BDRVRawState *s = bs->opaque;
int fd, ret;
ret = raw_normalize_devicepath(&filename);
if (ret != 0) {
return ret;
}
s->open_flags = open_flags | O_BINARY;
s->open_flags &= ~O_ACCMODE;
if (bdrv_flags & BDRV_O_RDWR) {
s->open_flags |= O_RDWR;
} else {
s->open_flags |= O_RDONLY;
}
/* Use O_DSYNC for write-through caching, no flags for write-back caching,
* and O_DIRECT for no caching. */
if ((bdrv_flags & BDRV_O_NOCACHE))
s->open_flags |= O_DIRECT;
if (!(bdrv_flags & BDRV_O_CACHE_WB))
s->open_flags |= O_DSYNC;
s->fd = -1;
fd = qemu_open(filename, s->open_flags, 0644);
if (fd < 0) {
ret = -errno;
if (ret == -EROFS)
ret = -EACCES;
return ret;
}
s->fd = fd;
s->aligned_buf = NULL;
if ((bdrv_flags & BDRV_O_NOCACHE)) {
/*
* Allocate a buffer for read/modify/write cycles. Chose the size
* pessimistically as we don't know the block size yet.
*/
s->aligned_buf_size = 32 * MAX_BLOCKSIZE;
s->aligned_buf = qemu_memalign(MAX_BLOCKSIZE, s->aligned_buf_size);
if (s->aligned_buf == NULL) {
goto out_close;
}
}
#ifdef CONFIG_LINUX_AIO
if ((bdrv_flags & (BDRV_O_NOCACHE|BDRV_O_NATIVE_AIO)) ==
(BDRV_O_NOCACHE|BDRV_O_NATIVE_AIO)) {
/* We're falling back to POSIX AIO in some cases */
paio_init();
s->aio_ctx = laio_init();
if (!s->aio_ctx) {
goto out_free_buf;
}
s->use_aio = 1;
} else
#endif
{
if (paio_init() < 0) {
goto out_free_buf;
}
#ifdef CONFIG_LINUX_AIO
s->use_aio = 0;
#endif
}
#ifdef CONFIG_XFS
if (platform_test_xfs_fd(s->fd)) {
s->is_xfs = 1;
}
#endif
return 0;
out_free_buf:
qemu_vfree(s->aligned_buf);
out_close:
close(fd);
return -errno;
}
void kvm_arch_save_regs(CPUState *env)
{
struct kvm_regs regs;
struct kvm_fpu fpu;
struct kvm_sregs sregs;
struct kvm_msr_entry msrs[100];
uint32_t hflags;
uint32_t i, n, rc, bit;
assert(kvm_cpu_is_stopped(env) || env->thread_id == kvm_get_thread_id());
kvm_get_regs(env, ®s);
env->regs[R_EAX] = regs.rax;
env->regs[R_EBX] = regs.rbx;
env->regs[R_ECX] = regs.rcx;
env->regs[R_EDX] = regs.rdx;
env->regs[R_ESI] = regs.rsi;
env->regs[R_EDI] = regs.rdi;
env->regs[R_ESP] = regs.rsp;
env->regs[R_EBP] = regs.rbp;
#ifdef TARGET_X86_64
env->regs[8] = regs.r8;
env->regs[9] = regs.r9;
env->regs[10] = regs.r10;
env->regs[11] = regs.r11;
env->regs[12] = regs.r12;
env->regs[13] = regs.r13;
env->regs[14] = regs.r14;
env->regs[15] = regs.r15;
#endif
env->eflags = regs.rflags;
env->eip = regs.rip;
#ifdef KVM_CAP_XSAVE
if (kvm_check_extension(kvm_state, KVM_CAP_XSAVE)) {
struct kvm_xsave* xsave;
uint16_t cwd, swd, twd, fop;
xsave = qemu_memalign(4096, sizeof(struct kvm_xsave));
kvm_get_xsave(env, xsave);
cwd = (uint16_t)xsave->region[0];
swd = (uint16_t)(xsave->region[0] >> 16);
twd = (uint16_t)xsave->region[1];
fop = (uint16_t)(xsave->region[1] >> 16);
env->fpstt = (swd >> 11) & 7;
env->fpus = swd;
env->fpuc = cwd;
for (i = 0; i < 8; ++i)
env->fptags[i] = !((twd >> i) & 1);
env->mxcsr = xsave->region[XSAVE_MXCSR];
memcpy(env->fpregs, &xsave->region[XSAVE_ST_SPACE],
sizeof env->fpregs);
memcpy(env->xmm_regs, &xsave->region[XSAVE_XMM_SPACE],
sizeof env->xmm_regs);
env->xstate_bv = *(uint64_t *)&xsave->region[XSAVE_XSTATE_BV];
memcpy(env->ymmh_regs, &xsave->region[XSAVE_YMMH_SPACE],
sizeof env->ymmh_regs);
if (kvm_check_extension(kvm_state, KVM_CAP_XCRS)) {
struct kvm_xcrs xcrs;
kvm_get_xcrs(env, &xcrs);
if (xcrs.xcrs[0].xcr == 0)
env->xcr0 = xcrs.xcrs[0].value;
}
qemu_free(xsave);
} else {
void kvm_arch_load_regs(CPUState *env, int level)
{
struct kvm_regs regs;
struct kvm_fpu fpu;
struct kvm_sregs sregs;
struct kvm_msr_entry msrs[100];
int rc, n, i;
assert(kvm_cpu_is_stopped(env) || env->thread_id == kvm_get_thread_id());
regs.rax = env->regs[R_EAX];
regs.rbx = env->regs[R_EBX];
regs.rcx = env->regs[R_ECX];
regs.rdx = env->regs[R_EDX];
regs.rsi = env->regs[R_ESI];
regs.rdi = env->regs[R_EDI];
regs.rsp = env->regs[R_ESP];
regs.rbp = env->regs[R_EBP];
#ifdef TARGET_X86_64
regs.r8 = env->regs[8];
regs.r9 = env->regs[9];
regs.r10 = env->regs[10];
regs.r11 = env->regs[11];
regs.r12 = env->regs[12];
regs.r13 = env->regs[13];
regs.r14 = env->regs[14];
regs.r15 = env->regs[15];
#endif
regs.rflags = env->eflags;
regs.rip = env->eip;
kvm_set_regs(env, ®s);
#ifdef KVM_CAP_XSAVE
if (kvm_check_extension(kvm_state, KVM_CAP_XSAVE)) {
struct kvm_xsave* xsave;
uint16_t cwd, swd, twd, fop;
xsave = qemu_memalign(4096, sizeof(struct kvm_xsave));
memset(xsave, 0, sizeof(struct kvm_xsave));
cwd = swd = twd = fop = 0;
swd = env->fpus & ~(7 << 11);
swd |= (env->fpstt & 7) << 11;
cwd = env->fpuc;
for (i = 0; i < 8; ++i)
twd |= (!env->fptags[i]) << i;
xsave->region[0] = (uint32_t)(swd << 16) + cwd;
xsave->region[1] = (uint32_t)(fop << 16) + twd;
memcpy(&xsave->region[XSAVE_ST_SPACE], env->fpregs,
sizeof env->fpregs);
memcpy(&xsave->region[XSAVE_XMM_SPACE], env->xmm_regs,
sizeof env->xmm_regs);
xsave->region[XSAVE_MXCSR] = env->mxcsr;
*(uint64_t *)&xsave->region[XSAVE_XSTATE_BV] = env->xstate_bv;
memcpy(&xsave->region[XSAVE_YMMH_SPACE], env->ymmh_regs,
sizeof env->ymmh_regs);
kvm_set_xsave(env, xsave);
if (kvm_check_extension(kvm_state, KVM_CAP_XCRS)) {
struct kvm_xcrs xcrs;
xcrs.nr_xcrs = 1;
xcrs.flags = 0;
xcrs.xcrs[0].xcr = 0;
xcrs.xcrs[0].value = env->xcr0;
kvm_set_xcrs(env, &xcrs);
}
qemu_free(xsave);
} else {
#endif
memset(&fpu, 0, sizeof fpu);
fpu.fsw = env->fpus & ~(7 << 11);
fpu.fsw |= (env->fpstt & 7) << 11;
fpu.fcw = env->fpuc;
for (i = 0; i < 8; ++i)
fpu.ftwx |= (!env->fptags[i]) << i;
memcpy(fpu.fpr, env->fpregs, sizeof env->fpregs);
memcpy(fpu.xmm, env->xmm_regs, sizeof env->xmm_regs);
fpu.mxcsr = env->mxcsr;
kvm_set_fpu(env, &fpu);
#ifdef KVM_CAP_XSAVE
}
#endif
memset(sregs.interrupt_bitmap, 0, sizeof(sregs.interrupt_bitmap));
if (env->interrupt_injected >= 0) {
sregs.interrupt_bitmap[env->interrupt_injected / 64] |=
(uint64_t)1 << (env->interrupt_injected % 64);
}
if ((env->eflags & VM_MASK)) {
set_v8086_seg(&sregs.cs, &env->segs[R_CS]);
set_v8086_seg(&sregs.ds, &env->segs[R_DS]);
set_v8086_seg(&sregs.es, &env->segs[R_ES]);
set_v8086_seg(&sregs.fs, &env->segs[R_FS]);
set_v8086_seg(&sregs.gs, &env->segs[R_GS]);
set_v8086_seg(&sregs.ss, &env->segs[R_SS]);
} else {
set_seg(&sregs.cs, &env->segs[R_CS]);
set_seg(&sregs.ds, &env->segs[R_DS]);
set_seg(&sregs.es, &env->segs[R_ES]);
set_seg(&sregs.fs, &env->segs[R_FS]);
set_seg(&sregs.gs, &env->segs[R_GS]);
set_seg(&sregs.ss, &env->segs[R_SS]);
if (env->cr[0] & CR0_PE_MASK) {
/* force ss cpl to cs cpl */
sregs.ss.selector = (sregs.ss.selector & ~3) |
(sregs.cs.selector & 3);
sregs.ss.dpl = sregs.ss.selector & 3;
}
}
set_seg(&sregs.tr, &env->tr);
set_seg(&sregs.ldt, &env->ldt);
sregs.idt.limit = env->idt.limit;
sregs.idt.base = env->idt.base;
sregs.gdt.limit = env->gdt.limit;
sregs.gdt.base = env->gdt.base;
sregs.cr0 = env->cr[0];
sregs.cr2 = env->cr[2];
sregs.cr3 = env->cr[3];
sregs.cr4 = env->cr[4];
sregs.cr8 = cpu_get_apic_tpr(env->apic_state);
sregs.apic_base = cpu_get_apic_base(env->apic_state);
sregs.efer = env->efer;
kvm_set_sregs(env, &sregs);
/* msrs */
n = 0;
/* Remember to increase msrs size if you add new registers below */
kvm_msr_entry_set(&msrs[n++], MSR_IA32_SYSENTER_CS, env->sysenter_cs);
kvm_msr_entry_set(&msrs[n++], MSR_IA32_SYSENTER_ESP, env->sysenter_esp);
kvm_msr_entry_set(&msrs[n++], MSR_IA32_SYSENTER_EIP, env->sysenter_eip);
if (kvm_has_msr_star)
kvm_msr_entry_set(&msrs[n++], MSR_STAR, env->star);
if (kvm_has_vm_hsave_pa)
kvm_msr_entry_set(&msrs[n++], MSR_VM_HSAVE_PA, env->vm_hsave);
#ifdef TARGET_X86_64
if (lm_capable_kernel) {
kvm_msr_entry_set(&msrs[n++], MSR_CSTAR, env->cstar);
kvm_msr_entry_set(&msrs[n++], MSR_KERNELGSBASE, env->kernelgsbase);
kvm_msr_entry_set(&msrs[n++], MSR_FMASK, env->fmask);
kvm_msr_entry_set(&msrs[n++], MSR_LSTAR , env->lstar);
}
#endif
if (level == KVM_PUT_FULL_STATE) {
/*
* KVM is yet unable to synchronize TSC values of multiple VCPUs on
* writeback. Until this is fixed, we only write the offset to SMP
* guests after migration, desynchronizing the VCPUs, but avoiding
* huge jump-backs that would occur without any writeback at all.
*/
if (smp_cpus == 1 || env->tsc != 0) {
kvm_msr_entry_set(&msrs[n++], MSR_IA32_TSC, env->tsc);
}
kvm_msr_entry_set(&msrs[n++], MSR_KVM_SYSTEM_TIME, env->system_time_msr);
kvm_msr_entry_set(&msrs[n++], MSR_KVM_WALL_CLOCK, env->wall_clock_msr);
}
#ifdef KVM_CAP_MCE
if (env->mcg_cap) {
if (level == KVM_PUT_RESET_STATE)
kvm_msr_entry_set(&msrs[n++], MSR_MCG_STATUS, env->mcg_status);
else if (level == KVM_PUT_FULL_STATE) {
kvm_msr_entry_set(&msrs[n++], MSR_MCG_STATUS, env->mcg_status);
kvm_msr_entry_set(&msrs[n++], MSR_MCG_CTL, env->mcg_ctl);
for (i = 0; i < (env->mcg_cap & 0xff); i++)
kvm_msr_entry_set(&msrs[n++], MSR_MC0_CTL + i, env->mce_banks[i]);
}
}
#endif
rc = kvm_set_msrs(env, msrs, n);
if (rc == -1)
perror("kvm_set_msrs FAILED");
if (level >= KVM_PUT_RESET_STATE) {
kvm_arch_load_mpstate(env);
kvm_load_lapic(env);
}
if (level == KVM_PUT_FULL_STATE) {
if (env->kvm_vcpu_update_vapic)
kvm_tpr_enable_vapic(env);
}
kvm_put_vcpu_events(env, level);
kvm_put_debugregs(env);
/* must be last */
kvm_guest_debug_workarounds(env);
}
static int ioreq_runio_qemu_aio(struct ioreq *ioreq)
{
struct XenBlkDev *blkdev = ioreq->blkdev;
ioreq->buf = qemu_memalign(XC_PAGE_SIZE, ioreq->size);
if (ioreq->req.nr_segments &&
(ioreq->req.operation == BLKIF_OP_WRITE ||
ioreq->req.operation == BLKIF_OP_FLUSH_DISKCACHE) &&
ioreq_grant_copy(ioreq)) {
qemu_vfree(ioreq->buf);
goto err;
}
ioreq->aio_inflight++;
if (ioreq->presync) {
blk_aio_flush(ioreq->blkdev->blk, qemu_aio_complete, ioreq);
return 0;
}
switch (ioreq->req.operation) {
case BLKIF_OP_READ:
qemu_iovec_add(&ioreq->v, ioreq->buf, ioreq->size);
block_acct_start(blk_get_stats(blkdev->blk), &ioreq->acct,
ioreq->v.size, BLOCK_ACCT_READ);
ioreq->aio_inflight++;
blk_aio_preadv(blkdev->blk, ioreq->start, &ioreq->v, 0,
qemu_aio_complete, ioreq);
break;
case BLKIF_OP_WRITE:
case BLKIF_OP_FLUSH_DISKCACHE:
if (!ioreq->req.nr_segments) {
break;
}
qemu_iovec_add(&ioreq->v, ioreq->buf, ioreq->size);
block_acct_start(blk_get_stats(blkdev->blk), &ioreq->acct,
ioreq->v.size,
ioreq->req.operation == BLKIF_OP_WRITE ?
BLOCK_ACCT_WRITE : BLOCK_ACCT_FLUSH);
ioreq->aio_inflight++;
blk_aio_pwritev(blkdev->blk, ioreq->start, &ioreq->v, 0,
qemu_aio_complete, ioreq);
break;
case BLKIF_OP_DISCARD:
{
struct blkif_request_discard *req = (void *)&ioreq->req;
if (!blk_split_discard(ioreq, req->sector_number, req->nr_sectors)) {
goto err;
}
break;
}
default:
/* unknown operation (shouldn't happen -- parse catches this) */
goto err;
}
qemu_aio_complete(ioreq, 0);
return 0;
err:
ioreq_finish(ioreq);
ioreq->status = BLKIF_RSP_ERROR;
return -1;
}
static size_t handle_aiocb_rw(struct qemu_paiocb *aiocb)
{
size_t nbytes;
char *buf;
if (!aiocb_needs_copy(aiocb)) {
/*
* If there is just a single buffer, and it is properly aligned
* we can just use plain pread/pwrite without any problems.
*/
if (aiocb->aio_niov == 1)
return handle_aiocb_rw_linear(aiocb, aiocb->aio_iov->iov_base);
/*
* We have more than one iovec, and all are properly aligned.
*
* Try preadv/pwritev first and fall back to linearizing the
* buffer if it's not supported.
*/
if (preadv_present) {
nbytes = handle_aiocb_rw_vector(aiocb);
if (nbytes == aiocb->aio_nbytes)
return nbytes;
if (nbytes < 0 && nbytes != -ENOSYS)
return nbytes;
preadv_present = 0;
}
/*
* XXX(hch): short read/write. no easy way to handle the reminder
* using these interfaces. For now retry using plain
* pread/pwrite?
*/
}
/*
* Ok, we have to do it the hard way, copy all segments into
* a single aligned buffer.
*/
buf = qemu_memalign(512, aiocb->aio_nbytes);
if (aiocb->aio_type == QEMU_PAIO_WRITE) {
char *p = buf;
int i;
for (i = 0; i < aiocb->aio_niov; ++i) {
memcpy(p, aiocb->aio_iov[i].iov_base, aiocb->aio_iov[i].iov_len);
p += aiocb->aio_iov[i].iov_len;
}
}
nbytes = handle_aiocb_rw_linear(aiocb, buf);
if (aiocb->aio_type != QEMU_PAIO_WRITE) {
char *p = buf;
size_t count = aiocb->aio_nbytes, copy;
int i;
for (i = 0; i < aiocb->aio_niov && count; ++i) {
copy = count;
if (copy > aiocb->aio_iov[i].iov_len)
copy = aiocb->aio_iov[i].iov_len;
memcpy(aiocb->aio_iov[i].iov_base, p, copy);
p += copy;
count -= copy;
}
}
qemu_vfree(buf);
return nbytes;
}