/* * 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 <glib.h> #include <glib/gprintf.h> #include <sys/types.h> #include <dirent.h> #include <sys/time.h> #include <utime.h> #include <sys/uio.h> #include <string.h> #include <stdint.h> #include <errno.h> #include "compiler.h" #include "virtio-9p-marshal.h" #include "bswap.h" void v9fs_string_free(V9fsString *str) { g_free(str->data); str->data = NULL; str->size = 0; } void v9fs_string_null(V9fsString *str) { v9fs_string_free(str); } void GCC_FMT_ATTR(2, 3) v9fs_string_sprintf(V9fsString *str, const char *fmt, ...) { va_list ap; v9fs_string_free(str); va_start(ap, fmt); str->size = g_vasprintf(&str->data, fmt, ap); va_end(ap); } void v9fs_string_copy(V9fsString *lhs, V9fsString *rhs) { v9fs_string_free(lhs); v9fs_string_sprintf(lhs, "%s", rhs->data); } static ssize_t v9fs_packunpack(void *addr, struct iovec *sg, int sg_count, size_t offset, size_t size, int pack) { int i = 0; size_t copied = 0; size_t req_size = size; 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; } } } if (copied < req_size) { /* * We copied less that requested size. error out */ return -ENOBUFS; } return copied; } static ssize_t v9fs_unpack(void *dst, struct iovec *out_sg, int out_num, size_t offset, size_t size) { return v9fs_packunpack(dst, out_sg, out_num, offset, size, 0); } ssize_t v9fs_pack(struct iovec *in_sg, int in_num, size_t offset, const void *src, size_t size) { return v9fs_packunpack((void *)src, in_sg, in_num, offset, size, 1); } ssize_t v9fs_unmarshal(struct iovec *out_sg, int out_num, size_t offset, int bswap, const char *fmt, ...) { int i; va_list ap; ssize_t copied = 0; size_t old_offset = offset; va_start(ap, fmt); for (i = 0; fmt[i]; i++) { switch (fmt[i]) { case 'b': { uint8_t *valp = va_arg(ap, uint8_t *); copied = v9fs_unpack(valp, out_sg, out_num, offset, sizeof(*valp)); break; } case 'w': { uint16_t val, *valp; valp = va_arg(ap, uint16_t *); copied = v9fs_unpack(&val, out_sg, out_num, offset, sizeof(val)); if (bswap) { *valp = le16_to_cpu(val); } else { *valp = val; } break; } case 'd': { uint32_t val, *valp; valp = va_arg(ap, uint32_t *); copied = v9fs_unpack(&val, out_sg, out_num, offset, sizeof(val)); if (bswap) { *valp = le32_to_cpu(val); } else { *valp = val; } break; } case 'q': { uint64_t val, *valp; valp = va_arg(ap, uint64_t *); copied = v9fs_unpack(&val, out_sg, out_num, offset, sizeof(val)); if (bswap) { *valp = le64_to_cpu(val); } else { *valp = val; } break; } case 's': { V9fsString *str = va_arg(ap, V9fsString *); copied = v9fs_unmarshal(out_sg, out_num, offset, bswap, "w", &str->size); if (copied > 0) { offset += copied; str->data = g_malloc(str->size + 1); copied = v9fs_unpack(str->data, out_sg, out_num, offset, str->size); if (copied > 0) { str->data[str->size] = 0; } else { v9fs_string_free(str); } } break; } case 'Q': { V9fsQID *qidp = va_arg(ap, V9fsQID *); copied = v9fs_unmarshal(out_sg, out_num, offset, bswap, "bdq", &qidp->type, &qidp->version, &qidp->path); break; } case 'S': { V9fsStat *statp = va_arg(ap, V9fsStat *); copied = v9fs_unmarshal(out_sg, out_num, offset, bswap, "wwdQdddqsssssddd", &statp->size, &statp->type, &statp->dev, &statp->qid, &statp->mode, &statp->atime, &statp->mtime, &statp->length, &statp->name, &statp->uid, &statp->gid, &statp->muid, &statp->extension, &statp->n_uid, &statp->n_gid, &statp->n_muid); break; } case 'I': { V9fsIattr *iattr = va_arg(ap, V9fsIattr *); copied = v9fs_unmarshal(out_sg, out_num, offset, bswap, "ddddqqqqq", &iattr->valid, &iattr->mode, &iattr->uid, &iattr->gid, &iattr->size, &iattr->atime_sec, &iattr->atime_nsec, &iattr->mtime_sec, &iattr->mtime_nsec); break; } default: break; } if (copied < 0) { va_end(ap); return copied; } offset += copied; } va_end(ap); return offset - old_offset; } ssize_t v9fs_marshal(struct iovec *in_sg, int in_num, size_t offset, int bswap, const char *fmt, ...) { int i; va_list ap; ssize_t copied = 0; size_t old_offset = offset; va_start(ap, fmt); for (i = 0; fmt[i]; i++) { switch (fmt[i]) { case 'b': { uint8_t val = va_arg(ap, int); copied = v9fs_pack(in_sg, in_num, offset, &val, sizeof(val)); break; } case 'w': { uint16_t val; if (bswap) { cpu_to_le16w(&val, va_arg(ap, int)); } else { val = va_arg(ap, int); } copied = v9fs_pack(in_sg, in_num, offset, &val, sizeof(val)); break; } case 'd': { uint32_t val; if (bswap) { cpu_to_le32w(&val, va_arg(ap, uint32_t)); } else { val = va_arg(ap, uint32_t); } copied = v9fs_pack(in_sg, in_num, offset, &val, sizeof(val)); break; } case 'q': { uint64_t val; if (bswap) { cpu_to_le64w(&val, va_arg(ap, uint64_t)); } else { val = va_arg(ap, uint64_t); } copied = v9fs_pack(in_sg, in_num, offset, &val, sizeof(val)); break; } case 's': { V9fsString *str = va_arg(ap, V9fsString *); copied = v9fs_marshal(in_sg, in_num, offset, bswap, "w", str->size); if (copied > 0) { offset += copied; copied = v9fs_pack(in_sg, in_num, offset, str->data, str->size); } break; } case 'Q': { V9fsQID *qidp = va_arg(ap, V9fsQID *); copied = v9fs_marshal(in_sg, in_num, offset, bswap, "bdq", qidp->type, qidp->version, qidp->path); break; } case 'S': { V9fsStat *statp = va_arg(ap, V9fsStat *); copied = v9fs_marshal(in_sg, in_num, offset, bswap, "wwdQdddqsssssddd", statp->size, statp->type, statp->dev, &statp->qid, statp->mode, statp->atime, statp->mtime, statp->length, &statp->name, &statp->uid, &statp->gid, &statp->muid, &statp->extension, statp->n_uid, statp->n_gid, statp->n_muid); break; } case 'A': { V9fsStatDotl *statp = va_arg(ap, V9fsStatDotl *); copied = v9fs_marshal(in_sg, in_num, offset, bswap, "qQdddqqqqqqqqqqqqqqq", statp->st_result_mask, &statp->qid, statp->st_mode, statp->st_uid, statp->st_gid, statp->st_nlink, statp->st_rdev, statp->st_size, statp->st_blksize, statp->st_blocks, statp->st_atime_sec, statp->st_atime_nsec, statp->st_mtime_sec, statp->st_mtime_nsec, statp->st_ctime_sec, statp->st_ctime_nsec, statp->st_btime_sec, statp->st_btime_nsec, statp->st_gen, statp->st_data_version); break; } default: break; } if (copied < 0) { va_end(ap); return copied; } offset += copied; } va_end(ap); return offset - old_offset; }