diff options
Diffstat (limited to 'hw/virtio-9p.c')
| -rw-r--r-- | hw/virtio-9p.c | 307 |
1 files changed, 307 insertions, 0 deletions
diff --git a/hw/virtio-9p.c b/hw/virtio-9p.c new file mode 100644 index 0000000000..abd01c16b6 --- /dev/null +++ b/hw/virtio-9p.c @@ -0,0 +1,307 @@ +/* + * Virtio 9p backend + * + * Copyright IBM, Corp. 2010 + * + * Authors: + * Anthony Liguori <aliguori@us.ibm.com> + * + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + * + */ + +#include "virtio.h" +#include "pc.h" +#include "qemu_socket.h" +#include "virtio-9p.h" +#include "fsdev/qemu-fsdev.h" +#include "virtio-9p-debug.h" + +int dotu = 1; +int debug_9p_pdu; + +static V9fsPDU *alloc_pdu(V9fsState *s) +{ + V9fsPDU *pdu = NULL; + + if (!QLIST_EMPTY(&s->free_list)) { + pdu = QLIST_FIRST(&s->free_list); + QLIST_REMOVE(pdu, next); + } + return pdu; +} + +static void free_pdu(V9fsState *s, V9fsPDU *pdu) +{ + if (pdu) { + QLIST_INSERT_HEAD(&s->free_list, pdu, next); + } +} + +size_t pdu_packunpack(void *addr, struct iovec *sg, int sg_count, + size_t offset, size_t size, int pack) +{ + int i = 0; + size_t copied = 0; + + for (i = 0; size && i < sg_count; i++) { + size_t len; + if (offset >= sg[i].iov_len) { + /* skip this sg */ + offset -= sg[i].iov_len; + continue; + } else { + len = MIN(sg[i].iov_len - offset, size); + if (pack) { + memcpy(sg[i].iov_base + offset, addr, len); + } else { + memcpy(addr, sg[i].iov_base + offset, len); + } + size -= len; + copied += len; + addr += len; + if (size) { + offset = 0; + continue; + } + } + } + + return copied; +} + +static void v9fs_version(V9fsState *s, V9fsPDU *pdu) +{ + if (debug_9p_pdu) { + pprint_pdu(pdu); + } +} + +static void v9fs_attach(V9fsState *s, V9fsPDU *pdu) +{ + if (debug_9p_pdu) { + pprint_pdu(pdu); + } +} + +static void v9fs_stat(V9fsState *s, V9fsPDU *pdu) +{ + if (debug_9p_pdu) { + pprint_pdu(pdu); + } +} + +static void v9fs_walk(V9fsState *s, V9fsPDU *pdu) +{ + if (debug_9p_pdu) { + pprint_pdu(pdu); + } +} + +static void v9fs_clunk(V9fsState *s, V9fsPDU *pdu) +{ + if (debug_9p_pdu) { + pprint_pdu(pdu); + } +} + +static void v9fs_open(V9fsState *s, V9fsPDU *pdu) +{ if (debug_9p_pdu) { + pprint_pdu(pdu); + } +} + +static void v9fs_read(V9fsState *s, V9fsPDU *pdu) +{ + if (debug_9p_pdu) { + pprint_pdu(pdu); + } +} + +static void v9fs_write(V9fsState *s, V9fsPDU *pdu) +{ + if (debug_9p_pdu) { + pprint_pdu(pdu); + } +} + +static void v9fs_create(V9fsState *s, V9fsPDU *pdu) +{ + if (debug_9p_pdu) { + pprint_pdu(pdu); + } +} + +static void v9fs_flush(V9fsState *s, V9fsPDU *pdu) +{ + if (debug_9p_pdu) { + pprint_pdu(pdu); + } +} + +static void v9fs_remove(V9fsState *s, V9fsPDU *pdu) +{ + if (debug_9p_pdu) { + pprint_pdu(pdu); + } +} + +static void v9fs_wstat(V9fsState *s, V9fsPDU *pdu) +{ + if (debug_9p_pdu) { + pprint_pdu(pdu); + } +} + +typedef void (pdu_handler_t)(V9fsState *s, V9fsPDU *pdu); + +static pdu_handler_t *pdu_handlers[] = { + [P9_TVERSION] = v9fs_version, + [P9_TATTACH] = v9fs_attach, + [P9_TSTAT] = v9fs_stat, + [P9_TWALK] = v9fs_walk, + [P9_TCLUNK] = v9fs_clunk, + [P9_TOPEN] = v9fs_open, + [P9_TREAD] = v9fs_read, +#if 0 + [P9_TAUTH] = v9fs_auth, +#endif + [P9_TFLUSH] = v9fs_flush, + [P9_TCREATE] = v9fs_create, + [P9_TWRITE] = v9fs_write, + [P9_TWSTAT] = v9fs_wstat, + [P9_TREMOVE] = v9fs_remove, +}; + +static void submit_pdu(V9fsState *s, V9fsPDU *pdu) +{ + pdu_handler_t *handler; + + if (debug_9p_pdu) { + pprint_pdu(pdu); + } + + BUG_ON(pdu->id >= ARRAY_SIZE(pdu_handlers)); + + handler = pdu_handlers[pdu->id]; + BUG_ON(handler == NULL); + + handler(s, pdu); +} + +static void handle_9p_output(VirtIODevice *vdev, VirtQueue *vq) +{ + V9fsState *s = (V9fsState *)vdev; + V9fsPDU *pdu; + ssize_t len; + + while ((pdu = alloc_pdu(s)) && + (len = virtqueue_pop(vq, &pdu->elem)) != 0) { + uint8_t *ptr; + + BUG_ON(pdu->elem.out_num == 0 || pdu->elem.in_num == 0); + BUG_ON(pdu->elem.out_sg[0].iov_len < 7); + + ptr = pdu->elem.out_sg[0].iov_base; + + memcpy(&pdu->size, ptr, 4); + pdu->id = ptr[4]; + memcpy(&pdu->tag, ptr + 5, 2); + + submit_pdu(s, pdu); + } + + free_pdu(s, pdu); +} + +static uint32_t virtio_9p_get_features(VirtIODevice *vdev, uint32_t features) +{ + features |= 1 << VIRTIO_9P_MOUNT_TAG; + return features; +} + +static V9fsState *to_virtio_9p(VirtIODevice *vdev) +{ + return (V9fsState *)vdev; +} + +static void virtio_9p_get_config(VirtIODevice *vdev, uint8_t *config) +{ + struct virtio_9p_config *cfg; + V9fsState *s = to_virtio_9p(vdev); + + cfg = qemu_mallocz(sizeof(struct virtio_9p_config) + + s->tag_len); + stw_raw(&cfg->tag_len, s->tag_len); + memcpy(cfg->tag, s->tag, s->tag_len); + memcpy(config, cfg, s->config_size); + qemu_free(cfg); +} + +VirtIODevice *virtio_9p_init(DeviceState *dev, V9fsConf *conf) + { + V9fsState *s; + int i, len; + struct stat stat; + FsTypeEntry *fse; + + + s = (V9fsState *)virtio_common_init("virtio-9p", + VIRTIO_ID_9P, + sizeof(struct virtio_9p_config)+ + MAX_TAG_LEN, + sizeof(V9fsState)); + + /* initialize pdu allocator */ + QLIST_INIT(&s->free_list); + for (i = 0; i < (MAX_REQ - 1); i++) { + QLIST_INSERT_HEAD(&s->free_list, &s->pdus[i], next); + } + + s->vq = virtio_add_queue(&s->vdev, MAX_REQ, handle_9p_output); + + fse = get_fsdev_fsentry(conf->fsdev_id); + + if (!fse) { + /* We don't have a fsdev identified by fsdev_id */ + fprintf(stderr, "Virtio-9p device couldn't find fsdev " + "with the id %s\n", conf->fsdev_id); + exit(1); + } + + if (!fse->path || !conf->tag) { + /* we haven't specified a mount_tag or the path */ + fprintf(stderr, "fsdev with id %s needs path " + "and Virtio-9p device needs mount_tag arguments\n", + conf->fsdev_id); + exit(1); + } + + if (lstat(fse->path, &stat)) { + fprintf(stderr, "share path %s does not exist\n", fse->path); + exit(1); + } else if (!S_ISDIR(stat.st_mode)) { + fprintf(stderr, "share path %s is not a directory \n", fse->path); + exit(1); + } + + s->ctx.fs_root = qemu_strdup(fse->path); + len = strlen(conf->tag); + if (len > MAX_TAG_LEN) { + len = MAX_TAG_LEN; + } + /* s->tag is non-NULL terminated string */ + s->tag = qemu_malloc(len); + memcpy(s->tag, conf->tag, len); + s->tag_len = len; + s->ctx.uid = -1; + + s->ops = fse->ops; + s->vdev.get_features = virtio_9p_get_features; + s->config_size = sizeof(struct virtio_9p_config) + + s->tag_len; + s->vdev.get_config = virtio_9p_get_config; + + return &s->vdev; +} |