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-rw-r--r--tools/virtiofsd/buffer.c350
1 files changed, 0 insertions, 350 deletions
diff --git a/tools/virtiofsd/buffer.c b/tools/virtiofsd/buffer.c
deleted file mode 100644
index b5f04be..0000000
--- a/tools/virtiofsd/buffer.c
+++ /dev/null
@@ -1,350 +0,0 @@
-/*
- * FUSE: Filesystem in Userspace
- * Copyright (C) 2010 Miklos Szeredi <miklos@szeredi.hu>
- *
- * Functions for dealing with `struct fuse_buf` and `struct
- * fuse_bufvec`.
- *
- * This program can be distributed under the terms of the GNU LGPLv2.
- * See the file COPYING.LIB
- */
-
-#include "qemu/osdep.h"
-#include "fuse_i.h"
-#include "fuse_lowlevel.h"
-
-size_t fuse_buf_size(const struct fuse_bufvec *bufv)
-{
- size_t i;
- size_t size = 0;
-
- for (i = 0; i < bufv->count; i++) {
- if (bufv->buf[i].size == SIZE_MAX) {
- size = SIZE_MAX;
- } else {
- size += bufv->buf[i].size;
- }
- }
-
- return size;
-}
-
-static ssize_t fuse_buf_writev(struct fuse_buf *out_buf,
- struct fuse_bufvec *in_buf)
-{
- ssize_t res, i, j;
- size_t iovcnt = in_buf->count;
- struct iovec *iov;
- int fd = out_buf->fd;
-
- iov = g_try_new0(struct iovec, iovcnt);
- if (!iov) {
- return -ENOMEM;
- }
-
- for (i = 0, j = 0; i < iovcnt; i++) {
- /* Skip the buf with 0 size */
- if (in_buf->buf[i].size) {
- iov[j].iov_base = in_buf->buf[i].mem;
- iov[j].iov_len = in_buf->buf[i].size;
- j++;
- }
- }
-
- if (out_buf->flags & FUSE_BUF_FD_SEEK) {
- res = pwritev(fd, iov, iovcnt, out_buf->pos);
- } else {
- res = writev(fd, iov, iovcnt);
- }
-
- if (res == -1) {
- res = -errno;
- }
-
- g_free(iov);
- return res;
-}
-
-static size_t min_size(size_t s1, size_t s2)
-{
- return s1 < s2 ? s1 : s2;
-}
-
-static ssize_t fuse_buf_write(const struct fuse_buf *dst, size_t dst_off,
- const struct fuse_buf *src, size_t src_off,
- size_t len)
-{
- ssize_t res = 0;
- size_t copied = 0;
-
- while (len) {
- if (dst->flags & FUSE_BUF_FD_SEEK) {
- res = pwrite(dst->fd, (char *)src->mem + src_off, len,
- dst->pos + dst_off);
- } else {
- res = write(dst->fd, (char *)src->mem + src_off, len);
- }
- if (res == -1) {
- if (!copied) {
- return -errno;
- }
- break;
- }
- if (res == 0) {
- break;
- }
-
- copied += res;
- if (!(dst->flags & FUSE_BUF_FD_RETRY)) {
- break;
- }
-
- src_off += res;
- dst_off += res;
- len -= res;
- }
-
- return copied;
-}
-
-static ssize_t fuse_buf_read(const struct fuse_buf *dst, size_t dst_off,
- const struct fuse_buf *src, size_t src_off,
- size_t len)
-{
- ssize_t res = 0;
- size_t copied = 0;
-
- while (len) {
- if (src->flags & FUSE_BUF_FD_SEEK) {
- res = pread(src->fd, (char *)dst->mem + dst_off, len,
- src->pos + src_off);
- } else {
- res = read(src->fd, (char *)dst->mem + dst_off, len);
- }
- if (res == -1) {
- if (!copied) {
- return -errno;
- }
- break;
- }
- if (res == 0) {
- break;
- }
-
- copied += res;
- if (!(src->flags & FUSE_BUF_FD_RETRY)) {
- break;
- }
-
- dst_off += res;
- src_off += res;
- len -= res;
- }
-
- return copied;
-}
-
-static ssize_t fuse_buf_fd_to_fd(const struct fuse_buf *dst, size_t dst_off,
- const struct fuse_buf *src, size_t src_off,
- size_t len)
-{
- char buf[4096];
- struct fuse_buf tmp = {
- .size = sizeof(buf),
- .flags = 0,
- };
- ssize_t res;
- size_t copied = 0;
-
- tmp.mem = buf;
-
- while (len) {
- size_t this_len = min_size(tmp.size, len);
- size_t read_len;
-
- res = fuse_buf_read(&tmp, 0, src, src_off, this_len);
- if (res < 0) {
- if (!copied) {
- return res;
- }
- break;
- }
- if (res == 0) {
- break;
- }
-
- read_len = res;
- res = fuse_buf_write(dst, dst_off, &tmp, 0, read_len);
- if (res < 0) {
- if (!copied) {
- return res;
- }
- break;
- }
- if (res == 0) {
- break;
- }
-
- copied += res;
-
- if (res < this_len) {
- break;
- }
-
- dst_off += res;
- src_off += res;
- len -= res;
- }
-
- return copied;
-}
-
-static ssize_t fuse_buf_copy_one(const struct fuse_buf *dst, size_t dst_off,
- const struct fuse_buf *src, size_t src_off,
- size_t len)
-{
- int src_is_fd = src->flags & FUSE_BUF_IS_FD;
- int dst_is_fd = dst->flags & FUSE_BUF_IS_FD;
-
- if (!src_is_fd && !dst_is_fd) {
- char *dstmem = (char *)dst->mem + dst_off;
- char *srcmem = (char *)src->mem + src_off;
-
- if (dstmem != srcmem) {
- if (dstmem + len <= srcmem || srcmem + len <= dstmem) {
- memcpy(dstmem, srcmem, len);
- } else {
- memmove(dstmem, srcmem, len);
- }
- }
-
- return len;
- } else if (!src_is_fd) {
- return fuse_buf_write(dst, dst_off, src, src_off, len);
- } else if (!dst_is_fd) {
- return fuse_buf_read(dst, dst_off, src, src_off, len);
- } else {
- return fuse_buf_fd_to_fd(dst, dst_off, src, src_off, len);
- }
-}
-
-static const struct fuse_buf *fuse_bufvec_current(struct fuse_bufvec *bufv)
-{
- if (bufv->idx < bufv->count) {
- return &bufv->buf[bufv->idx];
- } else {
- return NULL;
- }
-}
-
-static int fuse_bufvec_advance(struct fuse_bufvec *bufv, size_t len)
-{
- const struct fuse_buf *buf = fuse_bufvec_current(bufv);
-
- if (!buf) {
- return 0;
- }
-
- bufv->off += len;
- assert(bufv->off <= buf->size);
- if (bufv->off == buf->size) {
- assert(bufv->idx < bufv->count);
- bufv->idx++;
- if (bufv->idx == bufv->count) {
- return 0;
- }
- bufv->off = 0;
- }
- return 1;
-}
-
-ssize_t fuse_buf_copy(struct fuse_bufvec *dstv, struct fuse_bufvec *srcv)
-{
- size_t copied = 0, i;
-
- if (dstv == srcv) {
- return fuse_buf_size(dstv);
- }
-
- /*
- * use writev to improve bandwidth when all the
- * src buffers already mapped by the daemon
- * process
- */
- for (i = 0; i < srcv->count; i++) {
- if (srcv->buf[i].flags & FUSE_BUF_IS_FD) {
- break;
- }
- }
- if ((i == srcv->count) && (dstv->count == 1) &&
- (dstv->idx == 0) &&
- (dstv->buf[0].flags & FUSE_BUF_IS_FD)) {
- dstv->buf[0].pos += dstv->off;
- return fuse_buf_writev(&dstv->buf[0], srcv);
- }
-
- for (;;) {
- const struct fuse_buf *src = fuse_bufvec_current(srcv);
- const struct fuse_buf *dst = fuse_bufvec_current(dstv);
- size_t src_len;
- size_t dst_len;
- size_t len;
- ssize_t res;
-
- if (src == NULL || dst == NULL) {
- break;
- }
-
- src_len = src->size - srcv->off;
- dst_len = dst->size - dstv->off;
- len = min_size(src_len, dst_len);
-
- res = fuse_buf_copy_one(dst, dstv->off, src, srcv->off, len);
- if (res < 0) {
- if (!copied) {
- return res;
- }
- break;
- }
- copied += res;
-
- if (!fuse_bufvec_advance(srcv, res) ||
- !fuse_bufvec_advance(dstv, res)) {
- break;
- }
-
- if (res < len) {
- break;
- }
- }
-
- return copied;
-}
-
-void *fuse_mbuf_iter_advance(struct fuse_mbuf_iter *iter, size_t len)
-{
- void *ptr;
-
- if (len > iter->size - iter->pos) {
- return NULL;
- }
-
- ptr = iter->mem + iter->pos;
- iter->pos += len;
- return ptr;
-}
-
-const char *fuse_mbuf_iter_advance_str(struct fuse_mbuf_iter *iter)
-{
- const char *str = iter->mem + iter->pos;
- size_t remaining = iter->size - iter->pos;
- size_t i;
-
- for (i = 0; i < remaining; i++) {
- if (str[i] == '\0') {
- iter->pos += i + 1;
- return str;
- }
- }
- return NULL;
-}
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