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-rw-r--r--block/raw-posix-aio.h8
-rw-r--r--block/raw-posix.c294
2 files changed, 294 insertions, 8 deletions
diff --git a/block/raw-posix-aio.h b/block/raw-posix-aio.h
index 6725135dd4..c714367401 100644
--- a/block/raw-posix-aio.h
+++ b/block/raw-posix-aio.h
@@ -27,14 +27,6 @@
#define QEMU_AIO_MISALIGNED 0x1000
-/* posix-aio-compat.c - thread pool based implementation */
-BlockDriverAIOCB *paio_submit(BlockDriverState *bs, int fd,
- int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
- BlockDriverCompletionFunc *cb, void *opaque, int type);
-BlockDriverAIOCB *paio_ioctl(BlockDriverState *bs, int fd,
- unsigned long int req, void *buf,
- BlockDriverCompletionFunc *cb, void *opaque);
-
/* linux-aio.c - Linux native implementation */
void *laio_init(void);
BlockDriverAIOCB *laio_submit(BlockDriverState *bs, void *aio_ctx, int fd,
diff --git a/block/raw-posix.c b/block/raw-posix.c
index 9ae2c505a8..4d6d5df5bc 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -27,6 +27,9 @@
#include "qemu-log.h"
#include "block_int.h"
#include "module.h"
+#include "trace.h"
+#include "thread-pool.h"
+#include "iov.h"
#include "block/raw-posix-aio.h"
#if defined(__APPLE__) && (__MACH__)
@@ -149,6 +152,20 @@ typedef struct BDRVRawReopenState {
static int fd_open(BlockDriverState *bs);
static int64_t raw_getlength(BlockDriverState *bs);
+typedef struct RawPosixAIOData {
+ BlockDriverState *bs;
+ 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 */
+ off_t aio_offset;
+ int aio_type;
+} RawPosixAIOData;
+
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
static int cdrom_reopen(BlockDriverState *bs);
#endif
@@ -426,6 +443,283 @@ static int qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov)
return 1;
}
+static ssize_t handle_aiocb_ioctl(RawPosixAIOData *aiocb)
+{
+ int ret;
+
+ ret = ioctl(aiocb->aio_fildes, aiocb->aio_ioctl_cmd, aiocb->aio_ioctl_buf);
+ if (ret == -1) {
+ return -errno;
+ }
+
+ /*
+ * This looks weird, but the aio code only considers a request
+ * successful if it has written the 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 ssize_t handle_aiocb_flush(RawPosixAIOData *aiocb)
+{
+ int ret;
+
+ ret = qemu_fdatasync(aiocb->aio_fildes);
+ if (ret == -1) {
+ return -errno;
+ }
+ return 0;
+}
+
+#ifdef CONFIG_PREADV
+
+static bool preadv_present = true;
+
+static ssize_t
+qemu_preadv(int fd, const struct iovec *iov, int nr_iov, off_t offset)
+{
+ return preadv(fd, iov, nr_iov, offset);
+}
+
+static ssize_t
+qemu_pwritev(int fd, const struct iovec *iov, int nr_iov, off_t offset)
+{
+ return pwritev(fd, iov, nr_iov, offset);
+}
+
+#else
+
+static bool preadv_present = false;
+
+static ssize_t
+qemu_preadv(int fd, const struct iovec *iov, int nr_iov, off_t offset)
+{
+ return -ENOSYS;
+}
+
+static ssize_t
+qemu_pwritev(int fd, const struct iovec *iov, int nr_iov, off_t offset)
+{
+ return -ENOSYS;
+}
+
+#endif
+
+static ssize_t handle_aiocb_rw_vector(RawPosixAIOData *aiocb)
+{
+ ssize_t len;
+
+ do {
+ if (aiocb->aio_type & QEMU_AIO_WRITE)
+ len = qemu_pwritev(aiocb->aio_fildes,
+ aiocb->aio_iov,
+ aiocb->aio_niov,
+ aiocb->aio_offset);
+ else
+ len = qemu_preadv(aiocb->aio_fildes,
+ aiocb->aio_iov,
+ aiocb->aio_niov,
+ aiocb->aio_offset);
+ } while (len == -1 && errno == EINTR);
+
+ if (len == -1) {
+ return -errno;
+ }
+ return len;
+}
+
+/*
+ * Read/writes the data to/from a given linear buffer.
+ *
+ * Returns the number of bytes handles or -errno in case of an error. Short
+ * reads are only returned if the end of the file is reached.
+ */
+static ssize_t handle_aiocb_rw_linear(RawPosixAIOData *aiocb, char *buf)
+{
+ ssize_t offset = 0;
+ ssize_t len;
+
+ while (offset < aiocb->aio_nbytes) {
+ if (aiocb->aio_type & QEMU_AIO_WRITE) {
+ len = pwrite(aiocb->aio_fildes,
+ (const char *)buf + offset,
+ aiocb->aio_nbytes - offset,
+ aiocb->aio_offset + offset);
+ } else {
+ len = pread(aiocb->aio_fildes,
+ buf + offset,
+ aiocb->aio_nbytes - offset,
+ aiocb->aio_offset + offset);
+ }
+ if (len == -1 && errno == EINTR) {
+ continue;
+ } else if (len == -1) {
+ offset = -errno;
+ break;
+ } else if (len == 0) {
+ break;
+ }
+ offset += len;
+ }
+
+ return offset;
+}
+
+static ssize_t handle_aiocb_rw(RawPosixAIOData *aiocb)
+{
+ ssize_t nbytes;
+ char *buf;
+
+ 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.
+ */
+ 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 ||
+ (nbytes < 0 && nbytes != -ENOSYS)) {
+ return nbytes;
+ }
+ preadv_present = false;
+ }
+
+ /*
+ * 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_blockalign(aiocb->bs, aiocb->aio_nbytes);
+ if (aiocb->aio_type & QEMU_AIO_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_AIO_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;
+}
+
+static int aio_worker(void *arg)
+{
+ RawPosixAIOData *aiocb = arg;
+ ssize_t ret = 0;
+
+ switch (aiocb->aio_type & QEMU_AIO_TYPE_MASK) {
+ case QEMU_AIO_READ:
+ ret = handle_aiocb_rw(aiocb);
+ if (ret >= 0 && ret < aiocb->aio_nbytes && aiocb->bs->growable) {
+ iov_memset(aiocb->aio_iov, aiocb->aio_niov, ret,
+ 0, aiocb->aio_nbytes - ret);
+
+ ret = aiocb->aio_nbytes;
+ }
+ if (ret == aiocb->aio_nbytes) {
+ ret = 0;
+ } else if (ret >= 0 && ret < aiocb->aio_nbytes) {
+ ret = -EINVAL;
+ }
+ break;
+ case QEMU_AIO_WRITE:
+ ret = handle_aiocb_rw(aiocb);
+ if (ret == aiocb->aio_nbytes) {
+ ret = 0;
+ } else if (ret >= 0 && ret < aiocb->aio_nbytes) {
+ ret = -EINVAL;
+ }
+ break;
+ case QEMU_AIO_FLUSH:
+ ret = handle_aiocb_flush(aiocb);
+ break;
+ case QEMU_AIO_IOCTL:
+ ret = handle_aiocb_ioctl(aiocb);
+ break;
+ default:
+ fprintf(stderr, "invalid aio request (0x%x)\n", aiocb->aio_type);
+ ret = -EINVAL;
+ break;
+ }
+
+ g_slice_free(RawPosixAIOData, aiocb);
+ return ret;
+}
+
+static BlockDriverAIOCB *paio_submit(BlockDriverState *bs, int fd,
+ int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
+ BlockDriverCompletionFunc *cb, void *opaque, int type)
+{
+ RawPosixAIOData *acb = g_slice_new(RawPosixAIOData);
+
+ acb->bs = bs;
+ acb->aio_type = type;
+ acb->aio_fildes = fd;
+
+ if (qiov) {
+ acb->aio_iov = qiov->iov;
+ acb->aio_niov = qiov->niov;
+ }
+ acb->aio_nbytes = nb_sectors * 512;
+ acb->aio_offset = sector_num * 512;
+
+ trace_paio_submit(acb, opaque, sector_num, nb_sectors, type);
+ return thread_pool_submit_aio(aio_worker, acb, cb, opaque);
+}
+
+static BlockDriverAIOCB *paio_ioctl(BlockDriverState *bs, int fd,
+ unsigned long int req, void *buf,
+ BlockDriverCompletionFunc *cb, void *opaque)
+{
+ RawPosixAIOData *acb = g_slice_new(RawPosixAIOData);
+
+ acb->bs = bs;
+ acb->aio_type = QEMU_AIO_IOCTL;
+ acb->aio_fildes = fd;
+ acb->aio_offset = 0;
+ acb->aio_ioctl_buf = buf;
+ acb->aio_ioctl_cmd = req;
+
+ return thread_pool_submit_aio(aio_worker, acb, cb, opaque);
+}
+
static BlockDriverAIOCB *raw_aio_submit(BlockDriverState *bs,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque, int type)
generated by cgit v1.2.3 (git 2.26.2) at 2024-11-29 09:03:57 +0000