diff options
| -rw-r--r-- | hw/9pfs/virtio-9p.c | 162 |
1 files changed, 60 insertions, 102 deletions
diff --git a/hw/9pfs/virtio-9p.c b/hw/9pfs/virtio-9p.c index 36a862f1f1..46dc9f7340 100644 --- a/hw/9pfs/virtio-9p.c +++ b/hw/9pfs/virtio-9p.c @@ -674,40 +674,6 @@ static size_t pdu_pack(V9fsPDU *pdu, size_t offset, const void *src, offset, size, 1); } -static int pdu_copy_sg(V9fsPDU *pdu, size_t offset, int rx, struct iovec *sg) -{ - size_t pos = 0; - int i, j; - struct iovec *src_sg; - unsigned int num; - - if (rx) { - src_sg = pdu->elem.in_sg; - num = pdu->elem.in_num; - } else { - src_sg = pdu->elem.out_sg; - num = pdu->elem.out_num; - } - - j = 0; - for (i = 0; i < num; i++) { - if (offset <= pos) { - sg[j].iov_base = src_sg[i].iov_base; - sg[j].iov_len = src_sg[i].iov_len; - j++; - } else if (offset < (src_sg[i].iov_len + pos)) { - sg[j].iov_base = src_sg[i].iov_base; - sg[j].iov_len = src_sg[i].iov_len; - sg[j].iov_base += (offset - pos); - sg[j].iov_len -= (offset - pos); - j++; - } - pos += src_sg[i].iov_len; - } - - return j; -} - static size_t pdu_unmarshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...) { size_t old_offset = offset; @@ -743,12 +709,6 @@ static size_t pdu_unmarshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...) *valp = le64_to_cpu(val); break; } - case 'v': { - struct iovec *iov = va_arg(ap, struct iovec *); - int *iovcnt = va_arg(ap, int *); - *iovcnt = pdu_copy_sg(pdu, offset, 0, iov); - break; - } case 's': { V9fsString *str = va_arg(ap, V9fsString *); offset += pdu_unmarshal(pdu, offset, "w", &str->size); @@ -827,12 +787,6 @@ static size_t pdu_marshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...) offset += pdu_pack(pdu, offset, &val, sizeof(val)); break; } - case 'v': { - struct iovec *iov = va_arg(ap, struct iovec *); - int *iovcnt = va_arg(ap, int *); - *iovcnt = pdu_copy_sg(pdu, offset, 1, iov); - break; - } case 's': { V9fsString *str = va_arg(ap, V9fsString *); offset += pdu_marshal(pdu, offset, "w", str->size); @@ -1143,42 +1097,6 @@ static void stat_to_v9stat_dotl(V9fsState *s, const struct stat *stbuf, stat_to_qid(stbuf, &v9lstat->qid); } -static struct iovec *adjust_sg(struct iovec *sg, int len, int *iovcnt) -{ - while (len && *iovcnt) { - if (len < sg->iov_len) { - sg->iov_len -= len; - sg->iov_base += len; - len = 0; - } else { - len -= sg->iov_len; - sg++; - *iovcnt -= 1; - } - } - - return sg; -} - -static struct iovec *cap_sg(struct iovec *sg, int cap, int *cnt) -{ - int i; - int total = 0; - - for (i = 0; i < *cnt; i++) { - if ((total + sg[i].iov_len) > cap) { - sg[i].iov_len -= ((total + sg[i].iov_len) - cap); - i++; - break; - } - total += sg[i].iov_len; - } - - *cnt = i; - - return sg; -} - static void print_sg(struct iovec *sg, int cnt) { int i; @@ -1861,6 +1779,38 @@ out: return count; } +/* + * Create a QEMUIOVector for a sub-region of PDU iovecs + * + * @qiov: uninitialized QEMUIOVector + * @skip: number of bytes to skip from beginning of PDU + * @size: number of bytes to include + * @is_write: true - write, false - read + * + * The resulting QEMUIOVector has heap-allocated iovecs and must be cleaned up + * with qemu_iovec_destroy(). + */ +static void v9fs_init_qiov_from_pdu(QEMUIOVector *qiov, V9fsPDU *pdu, + uint64_t skip, size_t size, + bool is_write) +{ + QEMUIOVector elem; + struct iovec *iov; + unsigned int niov; + + if (is_write) { + iov = pdu->elem.out_sg; + niov = pdu->elem.out_num; + } else { + iov = pdu->elem.in_sg; + niov = pdu->elem.in_num; + } + + qemu_iovec_init_external(&elem, iov, niov); + qemu_iovec_init(qiov, niov); + qemu_iovec_copy(qiov, &elem, skip, size); +} + static void v9fs_read(void *opaque) { int32_t fid; @@ -1895,21 +1845,21 @@ static void v9fs_read(void *opaque) err += pdu_marshal(pdu, offset, "d", count); err += count; } else if (fidp->fid_type == P9_FID_FILE) { - int32_t cnt; + QEMUIOVector qiov_full; + QEMUIOVector qiov; int32_t len; - struct iovec *sg; - struct iovec iov[128]; /* FIXME: bad, bad, bad */ - sg = iov; - pdu_marshal(pdu, offset + 4, "v", sg, &cnt); - sg = cap_sg(sg, max_count, &cnt); + v9fs_init_qiov_from_pdu(&qiov_full, pdu, offset + 4, max_count, false); + qemu_iovec_init(&qiov, qiov_full.niov); do { + qemu_iovec_reset(&qiov); + qemu_iovec_copy(&qiov, &qiov_full, count, qiov_full.size - count); if (0) { - print_sg(sg, cnt); + print_sg(qiov.iov, qiov.niov); } /* Loop in case of EINTR */ do { - len = v9fs_co_preadv(pdu, fidp, sg, cnt, off); + len = v9fs_co_preadv(pdu, fidp, qiov.iov, qiov.niov, off); if (len >= 0) { off += len; count += len; @@ -1920,11 +1870,12 @@ static void v9fs_read(void *opaque) err = len; goto out; } - sg = adjust_sg(sg, len, &cnt); } while (count < max_count && len > 0); err = offset; err += pdu_marshal(pdu, offset, "d", count); err += count; + qemu_iovec_destroy(&qiov); + qemu_iovec_destroy(&qiov_full); } else if (fidp->fid_type == P9_FID_XATTR) { err = v9fs_xattr_read(s, pdu, fidp, off, max_count); } else { @@ -2095,7 +2046,6 @@ out: static void v9fs_write(void *opaque) { - int cnt; ssize_t err; int32_t fid; int64_t off; @@ -2104,13 +2054,14 @@ static void v9fs_write(void *opaque) int32_t total = 0; size_t offset = 7; V9fsFidState *fidp; - struct iovec iov[128]; /* FIXME: bad, bad, bad */ - struct iovec *sg = iov; V9fsPDU *pdu = opaque; V9fsState *s = pdu->s; + QEMUIOVector qiov_full; + QEMUIOVector qiov; - pdu_unmarshal(pdu, offset, "dqdv", &fid, &off, &count, sg, &cnt); - trace_v9fs_write(pdu->tag, pdu->id, fid, off, count, cnt); + offset += pdu_unmarshal(pdu, offset, "dqd", &fid, &off, &count); + v9fs_init_qiov_from_pdu(&qiov_full, pdu, offset, count, true); + trace_v9fs_write(pdu->tag, pdu->id, fid, off, count, qiov_full.niov); fidp = get_fid(pdu, fid); if (fidp == NULL) { @@ -2126,20 +2077,23 @@ static void v9fs_write(void *opaque) /* * setxattr operation */ - err = v9fs_xattr_write(s, pdu, fidp, off, count, sg, cnt); + err = v9fs_xattr_write(s, pdu, fidp, off, count, + qiov_full.iov, qiov_full.niov); goto out; } else { err = -EINVAL; goto out; } - sg = cap_sg(sg, count, &cnt); + qemu_iovec_init(&qiov, qiov_full.niov); do { + qemu_iovec_reset(&qiov); + qemu_iovec_copy(&qiov, &qiov_full, total, qiov_full.size - total); if (0) { - print_sg(sg, cnt); + print_sg(qiov.iov, qiov.niov); } /* Loop in case of EINTR */ do { - len = v9fs_co_pwritev(pdu, fidp, sg, cnt, off); + len = v9fs_co_pwritev(pdu, fidp, qiov.iov, qiov.niov, off); if (len >= 0) { off += len; total += len; @@ -2148,16 +2102,20 @@ static void v9fs_write(void *opaque) if (len < 0) { /* IO error return the error */ err = len; - goto out; + goto out_qiov; } - sg = adjust_sg(sg, len, &cnt); } while (total < count && len > 0); + + offset = 7; offset += pdu_marshal(pdu, offset, "d", total); err = offset; trace_v9fs_write_return(pdu->tag, pdu->id, total, err); +out_qiov: + qemu_iovec_destroy(&qiov); out: put_fid(pdu, fidp); out_nofid: + qemu_iovec_destroy(&qiov_full); complete_pdu(s, pdu, err); } |