*/
#include <sys/ioctl.h>
+#include <sys/types.h>
#include <pthread.h>
#include <unistd.h>
#include <errno.h>
#include <time.h>
+#include <signal.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
+
+#include "sys-queue.h"
#include "osdep.h"
#include "qemu-common.h"
+#include "block_int.h"
+
+#include "block/raw-posix-aio.h"
+
+
+struct qemu_paiocb {
+ BlockDriverAIOCB common;
+ int aio_fildes;
+ union {
+ struct iovec *aio_iov;
+ void *aio_ioctl_buf;
+ };
+ int aio_niov;
+ size_t aio_nbytes;
+#define aio_ioctl_cmd aio_nbytes /* for QEMU_AIO_IOCTL */
+ int ev_signo;
+ off_t aio_offset;
+
+ TAILQ_ENTRY(qemu_paiocb) node;
+ int aio_type;
+ ssize_t ret;
+ int active;
+ struct qemu_paiocb *next;
+};
+
+typedef struct PosixAioState {
+ int rfd, wfd;
+ struct qemu_paiocb *first_aio;
+} PosixAioState;
-#include "posix-aio-compat.h"
static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
static pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
static int idle_threads = 0;
static TAILQ_HEAD(, qemu_paiocb) request_list;
-#ifdef HAVE_PREADV
+#ifdef CONFIG_PREADV
static int preadv_present = 1;
#else
static int preadv_present = 0;
ret = ioctl(aiocb->aio_fildes, aiocb->aio_ioctl_cmd, aiocb->aio_ioctl_buf);
if (ret == -1)
return -errno;
- return ret;
+
+ /*
+ * This looks weird, but the aio code only consideres a request
+ * successfull if it has written the number full number of bytes.
+ *
+ * Now we overload aio_nbytes as aio_ioctl_cmd for the ioctl command,
+ * so in fact we return the ioctl command here to make posix_aio_read()
+ * happy..
+ */
+ return aiocb->aio_nbytes;
+}
+
+static size_t handle_aiocb_flush(struct qemu_paiocb *aiocb)
+{
+ int ret;
+
+ ret = fdatasync(aiocb->aio_fildes);
+ if (ret == -1)
+ return -errno;
+ return 0;
}
-#ifdef HAVE_PREADV
+#ifdef CONFIG_PREADV
static ssize_t
qemu_preadv(int fd, const struct iovec *iov, int nr_iov, off_t offset)
#endif
-/*
- * Check if we need to copy the data in the aiocb into a new
- * properly aligned buffer.
- */
-static int aiocb_needs_copy(struct qemu_paiocb *aiocb)
-{
- if (aiocb->aio_flags & QEMU_AIO_SECTOR_ALIGNED) {
- int i;
-
- for (i = 0; i < aiocb->aio_niov; i++)
- if ((uintptr_t) aiocb->aio_iov[i].iov_base % 512)
- return 1;
- }
-
- return 0;
-}
-
static size_t handle_aiocb_rw_vector(struct qemu_paiocb *aiocb)
{
size_t offset = 0;
ssize_t len;
do {
- if (aiocb->aio_type == QEMU_PAIO_WRITE)
+ if (aiocb->aio_type & QEMU_AIO_WRITE)
len = qemu_pwritev(aiocb->aio_fildes,
aiocb->aio_iov,
aiocb->aio_niov,
size_t len;
while (offset < aiocb->aio_nbytes) {
- if (aiocb->aio_type == QEMU_PAIO_WRITE)
+ if (aiocb->aio_type & QEMU_AIO_WRITE)
len = pwrite(aiocb->aio_fildes,
(const char *)buf + offset,
aiocb->aio_nbytes - offset,
size_t nbytes;
char *buf;
- if (!aiocb_needs_copy(aiocb)) {
+ if (!(aiocb->aio_type & QEMU_AIO_MISALIGNED)) {
/*
* If there is just a single buffer, and it is properly aligned
* we can just use plain pread/pwrite without any problems.
* a single aligned buffer.
*/
buf = qemu_memalign(512, aiocb->aio_nbytes);
- if (aiocb->aio_type == QEMU_PAIO_WRITE) {
+ if (aiocb->aio_type & QEMU_AIO_WRITE) {
char *p = buf;
int i;
}
nbytes = handle_aiocb_rw_linear(aiocb, buf);
- if (aiocb->aio_type != QEMU_PAIO_WRITE) {
+ if (!(aiocb->aio_type & QEMU_AIO_WRITE)) {
char *p = buf;
size_t count = aiocb->aio_nbytes, copy;
int i;
idle_threads--;
mutex_unlock(&lock);
- switch (aiocb->aio_type) {
- case QEMU_PAIO_READ:
- case QEMU_PAIO_WRITE:
+ switch (aiocb->aio_type & QEMU_AIO_TYPE_MASK) {
+ case QEMU_AIO_READ:
+ case QEMU_AIO_WRITE:
ret = handle_aiocb_rw(aiocb);
break;
- case QEMU_PAIO_IOCTL:
+ case QEMU_AIO_FLUSH:
+ ret = handle_aiocb_flush(aiocb);
+ break;
+ case QEMU_AIO_IOCTL:
ret = handle_aiocb_ioctl(aiocb);
break;
default:
thread_create(&thread_id, &attr, aio_thread, NULL);
}
-int qemu_paio_init(struct qemu_paioinit *aioinit)
-{
- int ret;
-
- ret = pthread_attr_init(&attr);
- if (ret) die2(ret, "pthread_attr_init");
-
- ret = pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
- if (ret) die2(ret, "pthread_attr_setdetachstate");
-
- TAILQ_INIT(&request_list);
-
- return 0;
-}
-
-static int qemu_paio_submit(struct qemu_paiocb *aiocb, int type)
+static void qemu_paio_submit(struct qemu_paiocb *aiocb)
{
- aiocb->aio_type = type;
aiocb->ret = -EINPROGRESS;
aiocb->active = 0;
mutex_lock(&lock);
TAILQ_INSERT_TAIL(&request_list, aiocb, node);
mutex_unlock(&lock);
cond_signal(&cond);
-
- return 0;
-}
-
-int qemu_paio_read(struct qemu_paiocb *aiocb)
-{
- return qemu_paio_submit(aiocb, QEMU_PAIO_READ);
-}
-
-int qemu_paio_write(struct qemu_paiocb *aiocb)
-{
- return qemu_paio_submit(aiocb, QEMU_PAIO_WRITE);
}
-int qemu_paio_ioctl(struct qemu_paiocb *aiocb)
-{
- return qemu_paio_submit(aiocb, QEMU_PAIO_IOCTL);
-}
-
-ssize_t qemu_paio_return(struct qemu_paiocb *aiocb)
+static ssize_t qemu_paio_return(struct qemu_paiocb *aiocb)
{
ssize_t ret;
return ret;
}
-int qemu_paio_error(struct qemu_paiocb *aiocb)
+static int qemu_paio_error(struct qemu_paiocb *aiocb)
{
ssize_t ret = qemu_paio_return(aiocb);
return ret;
}
-int qemu_paio_cancel(int fd, struct qemu_paiocb *aiocb)
+static void posix_aio_read(void *opaque)
{
+ PosixAioState *s = opaque;
+ struct qemu_paiocb *acb, **pacb;
int ret;
+ ssize_t len;
+
+ /* read all bytes from signal pipe */
+ for (;;) {
+ char bytes[16];
+
+ len = read(s->rfd, bytes, sizeof(bytes));
+ if (len == -1 && errno == EINTR)
+ continue; /* try again */
+ if (len == sizeof(bytes))
+ continue; /* more to read */
+ break;
+ }
+
+ for(;;) {
+ pacb = &s->first_aio;
+ for(;;) {
+ acb = *pacb;
+ if (!acb)
+ goto the_end;
+ ret = qemu_paio_error(acb);
+ if (ret == ECANCELED) {
+ /* remove the request */
+ *pacb = acb->next;
+ qemu_aio_release(acb);
+ } else if (ret != EINPROGRESS) {
+ /* end of aio */
+ if (ret == 0) {
+ ret = qemu_paio_return(acb);
+ if (ret == acb->aio_nbytes)
+ ret = 0;
+ else
+ ret = -EINVAL;
+ } else {
+ ret = -ret;
+ }
+ /* remove the request */
+ *pacb = acb->next;
+ /* call the callback */
+ acb->common.cb(acb->common.opaque, ret);
+ qemu_aio_release(acb);
+ break;
+ } else {
+ pacb = &acb->next;
+ }
+ }
+ }
+ the_end: ;
+}
+
+static int posix_aio_flush(void *opaque)
+{
+ PosixAioState *s = opaque;
+ return !!s->first_aio;
+}
+
+static PosixAioState *posix_aio_state;
+
+static void aio_signal_handler(int signum)
+{
+ if (posix_aio_state) {
+ char byte = 0;
+
+ write(posix_aio_state->wfd, &byte, sizeof(byte));
+ }
+
+ qemu_service_io();
+}
+
+static void paio_remove(struct qemu_paiocb *acb)
+{
+ struct qemu_paiocb **pacb;
+
+ /* remove the callback from the queue */
+ pacb = &posix_aio_state->first_aio;
+ for(;;) {
+ if (*pacb == NULL) {
+ fprintf(stderr, "paio_remove: aio request not found!\n");
+ break;
+ } else if (*pacb == acb) {
+ *pacb = acb->next;
+ qemu_aio_release(acb);
+ break;
+ }
+ pacb = &(*pacb)->next;
+ }
+}
+
+static void paio_cancel(BlockDriverAIOCB *blockacb)
+{
+ struct qemu_paiocb *acb = (struct qemu_paiocb *)blockacb;
+ int active = 0;
mutex_lock(&lock);
- if (!aiocb->active) {
- TAILQ_REMOVE(&request_list, aiocb, node);
- aiocb->ret = -ECANCELED;
- ret = QEMU_PAIO_CANCELED;
- } else if (aiocb->ret == -EINPROGRESS)
- ret = QEMU_PAIO_NOTCANCELED;
- else
- ret = QEMU_PAIO_ALLDONE;
+ if (!acb->active) {
+ TAILQ_REMOVE(&request_list, acb, node);
+ acb->ret = -ECANCELED;
+ } else if (acb->ret == -EINPROGRESS) {
+ active = 1;
+ }
mutex_unlock(&lock);
- return ret;
+ if (active) {
+ /* fail safe: if the aio could not be canceled, we wait for
+ it */
+ while (qemu_paio_error(acb) == EINPROGRESS)
+ ;
+ }
+
+ paio_remove(acb);
+}
+
+static AIOPool raw_aio_pool = {
+ .aiocb_size = sizeof(struct qemu_paiocb),
+ .cancel = paio_cancel,
+};
+
+BlockDriverAIOCB *paio_submit(BlockDriverState *bs, void *aio_ctx, int fd,
+ int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
+ BlockDriverCompletionFunc *cb, void *opaque, int type)
+{
+ struct qemu_paiocb *acb;
+
+ acb = qemu_aio_get(&raw_aio_pool, bs, cb, opaque);
+ if (!acb)
+ return NULL;
+ acb->aio_type = type;
+ acb->aio_fildes = fd;
+ acb->ev_signo = SIGUSR2;
+ if (qiov) {
+ acb->aio_iov = qiov->iov;
+ acb->aio_niov = qiov->niov;
+ }
+ acb->aio_nbytes = nb_sectors * 512;
+ acb->aio_offset = sector_num * 512;
+
+ acb->next = posix_aio_state->first_aio;
+ posix_aio_state->first_aio = acb;
+
+ qemu_paio_submit(acb);
+ return &acb->common;
+}
+
+BlockDriverAIOCB *paio_ioctl(BlockDriverState *bs, int fd,
+ unsigned long int req, void *buf,
+ BlockDriverCompletionFunc *cb, void *opaque)
+{
+ struct qemu_paiocb *acb;
+
+ acb = qemu_aio_get(&raw_aio_pool, bs, cb, opaque);
+ if (!acb)
+ return NULL;
+ acb->aio_type = QEMU_AIO_IOCTL;
+ acb->aio_fildes = fd;
+ acb->ev_signo = SIGUSR2;
+ acb->aio_offset = 0;
+ acb->aio_ioctl_buf = buf;
+ acb->aio_ioctl_cmd = req;
+
+ acb->next = posix_aio_state->first_aio;
+ posix_aio_state->first_aio = acb;
+
+ qemu_paio_submit(acb);
+ return &acb->common;
+}
+
+void *paio_init(void)
+{
+ struct sigaction act;
+ PosixAioState *s;
+ int fds[2];
+ int ret;
+
+ if (posix_aio_state)
+ return posix_aio_state;
+
+ s = qemu_malloc(sizeof(PosixAioState));
+
+ sigfillset(&act.sa_mask);
+ act.sa_flags = 0; /* do not restart syscalls to interrupt select() */
+ act.sa_handler = aio_signal_handler;
+ sigaction(SIGUSR2, &act, NULL);
+
+ s->first_aio = NULL;
+ if (pipe(fds) == -1) {
+ fprintf(stderr, "failed to create pipe\n");
+ return NULL;
+ }
+
+ s->rfd = fds[0];
+ s->wfd = fds[1];
+
+ fcntl(s->rfd, F_SETFL, O_NONBLOCK);
+ fcntl(s->wfd, F_SETFL, O_NONBLOCK);
+
+ qemu_aio_set_fd_handler(s->rfd, posix_aio_read, NULL, posix_aio_flush, s);
+
+ ret = pthread_attr_init(&attr);
+ if (ret)
+ die2(ret, "pthread_attr_init");
+
+ ret = pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
+ if (ret)
+ die2(ret, "pthread_attr_setdetachstate");
+
+ TAILQ_INIT(&request_list);
+
+ posix_aio_state = s;
+
+ return posix_aio_state;
}
projects / qemu / blobdiff