diff options
| -rw-r--r-- | block-raw-posix.c | 68 |
1 files changed, 65 insertions, 3 deletions
diff --git a/block-raw-posix.c b/block-raw-posix.c index 147730dd7..c46924185 100644 --- a/block-raw-posix.c +++ b/block-raw-posix.c @@ -84,10 +84,16 @@ reopen it to see if the disk has been changed */ #define FD_OPEN_TIMEOUT 1000 +/* posix-aio doesn't allow multiple outstanding requests to a single file + * descriptor. we implement a pool of dup()'d file descriptors to work + * around this */ +#define RAW_FD_POOL_SIZE 64 + typedef struct BDRVRawState { int fd; int type; unsigned int lseek_err_cnt; + int fd_pool[RAW_FD_POOL_SIZE]; #if defined(__linux__) /* linux floppy specific */ int fd_open_flags; @@ -109,6 +115,7 @@ static int raw_open(BlockDriverState *bs, const char *filename, int flags) { BDRVRawState *s = bs->opaque; int fd, open_flags, ret; + int i; posix_aio_init(); @@ -138,6 +145,8 @@ static int raw_open(BlockDriverState *bs, const char *filename, int flags) return ret; } s->fd = fd; + for (i = 0; i < RAW_FD_POOL_SIZE; i++) + s->fd_pool[i] = -1; #if defined(O_DIRECT) s->aligned_buf = NULL; if (flags & BDRV_O_DIRECT) { @@ -436,6 +445,7 @@ static int raw_pwrite(BlockDriverState *bs, int64_t offset, typedef struct RawAIOCB { BlockDriverAIOCB common; + int fd; struct aiocb aiocb; struct RawAIOCB *next; int ret; @@ -447,6 +457,38 @@ typedef struct PosixAioState RawAIOCB *first_aio; } PosixAioState; +static int raw_fd_pool_get(BDRVRawState *s) +{ + int i; + + for (i = 0; i < RAW_FD_POOL_SIZE; i++) { + /* already in use */ + if (s->fd_pool[i] != -1) + continue; + + /* try to dup file descriptor */ + s->fd_pool[i] = dup(s->fd); + if (s->fd_pool[i] != -1) + return s->fd_pool[i]; + } + + /* we couldn't dup the file descriptor so just use the main one */ + return s->fd; +} + +static void raw_fd_pool_put(RawAIOCB *acb) +{ + BDRVRawState *s = acb->common.bs->opaque; + int i; + + for (i = 0; i < RAW_FD_POOL_SIZE; i++) { + if (s->fd_pool[i] == acb->fd) { + close(s->fd_pool[i]); + s->fd_pool[i] = -1; + } + } +} + static void posix_aio_read(void *opaque) { PosixAioState *s = opaque; @@ -487,6 +529,7 @@ static void posix_aio_read(void *opaque) if (ret == ECANCELED) { /* remove the request */ *pacb = acb->next; + raw_fd_pool_put(acb); qemu_aio_release(acb); } else if (ret != EINPROGRESS) { /* end of aio */ @@ -503,6 +546,7 @@ static void posix_aio_read(void *opaque) *pacb = acb->next; /* call the callback */ acb->common.cb(acb->common.opaque, ret); + raw_fd_pool_put(acb); qemu_aio_release(acb); break; } else { @@ -577,7 +621,8 @@ static RawAIOCB *raw_aio_setup(BlockDriverState *bs, acb = qemu_aio_get(bs, cb, opaque); if (!acb) return NULL; - acb->aiocb.aio_fildes = s->fd; + acb->fd = raw_fd_pool_get(s); + acb->aiocb.aio_fildes = acb->fd; acb->aiocb.aio_sigevent.sigev_signo = SIGUSR2; acb->aiocb.aio_sigevent.sigev_notify = SIGEV_SIGNAL; acb->aiocb.aio_buf = buf; @@ -684,6 +729,7 @@ static void raw_aio_cancel(BlockDriverAIOCB *blockacb) break; } else if (*pacb == acb) { *pacb = acb->next; + raw_fd_pool_put(acb); qemu_aio_release(acb); break; } @@ -697,6 +743,18 @@ static int posix_aio_init(void) } #endif /* CONFIG_AIO */ +static void raw_close_fd_pool(BDRVRawState *s) +{ + int i; + + for (i = 0; i < RAW_FD_POOL_SIZE; i++) { + if (s->fd_pool[i] != -1) { + close(s->fd_pool[i]); + s->fd_pool[i] = -1; + } + } +} + static void raw_close(BlockDriverState *bs) { BDRVRawState *s = bs->opaque; @@ -708,6 +766,7 @@ static void raw_close(BlockDriverState *bs) qemu_free(s->aligned_buf); #endif } + raw_close_fd_pool(s); } static int raw_truncate(BlockDriverState *bs, int64_t offset) @@ -898,7 +957,7 @@ kern_return_t GetBSDPath( io_iterator_t mediaIterator, char *bsdPath, CFIndex ma static int hdev_open(BlockDriverState *bs, const char *filename, int flags) { BDRVRawState *s = bs->opaque; - int fd, open_flags, ret; + int fd, open_flags, ret, i; posix_aio_init(); @@ -963,6 +1022,8 @@ static int hdev_open(BlockDriverState *bs, const char *filename, int flags) return ret; } s->fd = fd; + for (i = 0; i < RAW_FD_POOL_SIZE; i++) + s->fd_pool[i] = -1; #if defined(__linux__) /* close fd so that we can reopen it as needed */ if (s->type == FTYPE_FD) { @@ -975,7 +1036,6 @@ static int hdev_open(BlockDriverState *bs, const char *filename, int flags) } #if defined(__linux__) - /* Note: we do not have a reliable method to detect if the floppy is present. The current method is to try to open the floppy at every I/O and to keep it opened during a few hundreds of ms. */ @@ -991,6 +1051,7 @@ static int fd_open(BlockDriverState *bs) (qemu_get_clock(rt_clock) - s->fd_open_time) >= FD_OPEN_TIMEOUT) { close(s->fd); s->fd = -1; + raw_close_fd_pool(s); #ifdef DEBUG_FLOPPY printf("Floppy closed\n"); #endif @@ -1091,6 +1152,7 @@ static int raw_eject(BlockDriverState *bs, int eject_flag) if (s->fd >= 0) { close(s->fd); s->fd = -1; + raw_close_fd_pool(s); } fd = open(bs->filename, s->fd_open_flags | O_NONBLOCK); if (fd >= 0) { |