qemu-e2k/hw/9pfs/9p-proxy.c

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/*
* 9p Proxy callback
*
* Copyright IBM, Corp. 2011
*
* Authors:
* M. Mohan Kumar <mohan@in.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 "qemu/osdep.h"
#include <sys/socket.h>
#include <sys/un.h>
#include "9p.h"
#include "qapi/error.h"
#include "qemu/cutils.h"
#include "qemu/error-report.h"
#include "qemu/option.h"
#include "fsdev/qemu-fsdev.h"
#include "9p-proxy.h"
typedef struct V9fsProxy {
int sockfd;
QemuMutex mutex;
struct iovec in_iovec;
struct iovec out_iovec;
} V9fsProxy;
/*
* Return received file descriptor on success in *status.
* errno is also returned on *status (which will be < 0)
* return < 0 on transport error.
*/
static int v9fs_receivefd(int sockfd, int *status)
{
struct iovec iov;
struct msghdr msg;
struct cmsghdr *cmsg;
int retval, data, fd;
union MsgControl msg_control;
iov.iov_base = &data;
iov.iov_len = sizeof(data);
memset(&msg, 0, sizeof(msg));
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
msg.msg_control = &msg_control;
msg.msg_controllen = sizeof(msg_control);
do {
retval = recvmsg(sockfd, &msg, 0);
} while (retval < 0 && errno == EINTR);
if (retval <= 0) {
return retval;
}
/*
* data is set to V9FS_FD_VALID, if ancillary data is sent. If this
* request doesn't need ancillary data (fd) or an error occurred,
* data is set to negative errno value.
*/
if (data != V9FS_FD_VALID) {
*status = data;
return 0;
}
/*
* File descriptor (fd) is sent in the ancillary data. Check if we
* indeed received it. One of the reasons to fail to receive it is if
* we exceeded the maximum number of file descriptors!
*/
for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)) ||
cmsg->cmsg_level != SOL_SOCKET ||
cmsg->cmsg_type != SCM_RIGHTS) {
continue;
}
fd = *((int *)CMSG_DATA(cmsg));
*status = fd;
return 0;
}
*status = -ENFILE; /* Ancillary data sent but not received */
return 0;
}
static ssize_t socket_read(int sockfd, void *buff, size_t size)
{
ssize_t retval, total = 0;
while (size) {
retval = read(sockfd, buff, size);
if (retval == 0) {
return -EIO;
}
if (retval < 0) {
if (errno == EINTR) {
continue;
}
return -errno;
}
size -= retval;
buff += retval;
total += retval;
}
return total;
}
/* Converts proxy_statfs to VFS statfs structure */
static void prstatfs_to_statfs(struct statfs *stfs, ProxyStatFS *prstfs)
{
memset(stfs, 0, sizeof(*stfs));
stfs->f_type = prstfs->f_type;
stfs->f_bsize = prstfs->f_bsize;
stfs->f_blocks = prstfs->f_blocks;
stfs->f_bfree = prstfs->f_bfree;
stfs->f_bavail = prstfs->f_bavail;
stfs->f_files = prstfs->f_files;
stfs->f_ffree = prstfs->f_ffree;
stfs->f_fsid.__val[0] = prstfs->f_fsid[0] & 0xFFFFFFFFU;
stfs->f_fsid.__val[1] = prstfs->f_fsid[1] >> 32 & 0xFFFFFFFFU;
stfs->f_namelen = prstfs->f_namelen;
stfs->f_frsize = prstfs->f_frsize;
}
/* Converts proxy_stat structure to VFS stat structure */
static void prstat_to_stat(struct stat *stbuf, ProxyStat *prstat)
{
memset(stbuf, 0, sizeof(*stbuf));
stbuf->st_dev = prstat->st_dev;
stbuf->st_ino = prstat->st_ino;
stbuf->st_nlink = prstat->st_nlink;
stbuf->st_mode = prstat->st_mode;
stbuf->st_uid = prstat->st_uid;
stbuf->st_gid = prstat->st_gid;
stbuf->st_rdev = prstat->st_rdev;
stbuf->st_size = prstat->st_size;
stbuf->st_blksize = prstat->st_blksize;
stbuf->st_blocks = prstat->st_blocks;
stbuf->st_atim.tv_sec = prstat->st_atim_sec;
stbuf->st_atim.tv_nsec = prstat->st_atim_nsec;
stbuf->st_mtime = prstat->st_mtim_sec;
stbuf->st_mtim.tv_nsec = prstat->st_mtim_nsec;
stbuf->st_ctime = prstat->st_ctim_sec;
stbuf->st_ctim.tv_nsec = prstat->st_ctim_nsec;
}
/*
* Response contains two parts
* {header, data}
* header.type == T_ERROR, data -> -errno
* header.type == T_SUCCESS, data -> response
* size of errno/response is given by header.size
* returns < 0, on transport error. response is
* valid only if status >= 0.
*/
static int v9fs_receive_response(V9fsProxy *proxy, int type,
int *status, void *response)
{
int retval;
ProxyHeader header;
struct iovec *reply = &proxy->in_iovec;
*status = 0;
reply->iov_len = 0;
retval = socket_read(proxy->sockfd, reply->iov_base, PROXY_HDR_SZ);
if (retval < 0) {
return retval;
}
reply->iov_len = PROXY_HDR_SZ;
retval = proxy_unmarshal(reply, 0, "dd", &header.type, &header.size);
assert(retval == 4 * 2);
/*
* if response size > PROXY_MAX_IO_SZ, read the response but ignore it and
* return -ENOBUFS
*/
if (header.size > PROXY_MAX_IO_SZ) {
int count;
while (header.size > 0) {
count = MIN(PROXY_MAX_IO_SZ, header.size);
count = socket_read(proxy->sockfd, reply->iov_base, count);
if (count < 0) {
return count;
}
header.size -= count;
}
*status = -ENOBUFS;
return 0;
}
retval = socket_read(proxy->sockfd,
reply->iov_base + PROXY_HDR_SZ, header.size);
if (retval < 0) {
return retval;
}
reply->iov_len += header.size;
/* there was an error during processing request */
if (header.type == T_ERROR) {
int ret;
ret = proxy_unmarshal(reply, PROXY_HDR_SZ, "d", status);
assert(ret == 4);
return 0;
}
switch (type) {
case T_LSTAT: {
ProxyStat prstat;
retval = proxy_unmarshal(reply, PROXY_HDR_SZ,
"qqqdddqqqqqqqqqq", &prstat.st_dev,
&prstat.st_ino, &prstat.st_nlink,
&prstat.st_mode, &prstat.st_uid,
&prstat.st_gid, &prstat.st_rdev,
&prstat.st_size, &prstat.st_blksize,
&prstat.st_blocks,
&prstat.st_atim_sec, &prstat.st_atim_nsec,
&prstat.st_mtim_sec, &prstat.st_mtim_nsec,
&prstat.st_ctim_sec, &prstat.st_ctim_nsec);
assert(retval == 8 * 3 + 4 * 3 + 8 * 10);
prstat_to_stat(response, &prstat);
break;
}
case T_STATFS: {
ProxyStatFS prstfs;
retval = proxy_unmarshal(reply, PROXY_HDR_SZ,
"qqqqqqqqqqq", &prstfs.f_type,
&prstfs.f_bsize, &prstfs.f_blocks,
&prstfs.f_bfree, &prstfs.f_bavail,
&prstfs.f_files, &prstfs.f_ffree,
&prstfs.f_fsid[0], &prstfs.f_fsid[1],
&prstfs.f_namelen, &prstfs.f_frsize);
assert(retval == 8 * 11);
prstatfs_to_statfs(response, &prstfs);
break;
}
case T_READLINK: {
V9fsString target;
v9fs_string_init(&target);
retval = proxy_unmarshal(reply, PROXY_HDR_SZ, "s", &target);
strcpy(response, target.data);
v9fs_string_free(&target);
break;
}
case T_LGETXATTR:
case T_LLISTXATTR: {
V9fsString xattr;
v9fs_string_init(&xattr);
retval = proxy_unmarshal(reply, PROXY_HDR_SZ, "s", &xattr);
memcpy(response, xattr.data, xattr.size);
v9fs_string_free(&xattr);
break;
}
case T_GETVERSION:
retval = proxy_unmarshal(reply, PROXY_HDR_SZ, "q", response);
assert(retval == 8);
break;
default:
return -1;
}
if (retval < 0) {
*status = retval;
}
return 0;
}
/*
* return < 0 on transport error.
* *status is valid only if return >= 0
*/
static int v9fs_receive_status(V9fsProxy *proxy,
struct iovec *reply, int *status)
{
int retval;
ProxyHeader header;
*status = 0;
reply->iov_len = 0;
retval = socket_read(proxy->sockfd, reply->iov_base, PROXY_HDR_SZ);
if (retval < 0) {
return retval;
}
reply->iov_len = PROXY_HDR_SZ;
retval = proxy_unmarshal(reply, 0, "dd", &header.type, &header.size);
assert(retval == 4 * 2);
retval = socket_read(proxy->sockfd,
reply->iov_base + PROXY_HDR_SZ, header.size);
if (retval < 0) {
return retval;
}
reply->iov_len += header.size;
retval = proxy_unmarshal(reply, PROXY_HDR_SZ, "d", status);
assert(retval == 4);
return 0;
}
/*
* Proxy->header and proxy->request written to socket by QEMU process.
* This request read by proxy helper process
* returns 0 on success and -errno on error
*/
static int v9fs_request(V9fsProxy *proxy, int type, void *response, ...)
{
dev_t rdev;
va_list ap;
int size = 0;
int retval = 0;
uint64_t offset;
ProxyHeader header = { 0, 0};
struct timespec spec[2];
int flags, mode, uid, gid;
V9fsString *name, *value;
V9fsString *path, *oldpath;
struct iovec *iovec = NULL, *reply = NULL;
qemu_mutex_lock(&proxy->mutex);
if (proxy->sockfd == -1) {
retval = -EIO;
goto err_out;
}
iovec = &proxy->out_iovec;
reply = &proxy->in_iovec;
va_start(ap, response);
switch (type) {
case T_OPEN:
path = va_arg(ap, V9fsString *);
flags = va_arg(ap, int);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "sd", path, flags);
if (retval > 0) {
header.size = retval;
header.type = T_OPEN;
}
break;
case T_CREATE:
path = va_arg(ap, V9fsString *);
flags = va_arg(ap, int);
mode = va_arg(ap, int);
uid = va_arg(ap, int);
gid = va_arg(ap, int);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "sdddd", path,
flags, mode, uid, gid);
if (retval > 0) {
header.size = retval;
header.type = T_CREATE;
}
break;
case T_MKNOD:
path = va_arg(ap, V9fsString *);
mode = va_arg(ap, int);
rdev = va_arg(ap, long int);
uid = va_arg(ap, int);
gid = va_arg(ap, int);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "ddsdq",
uid, gid, path, mode, rdev);
if (retval > 0) {
header.size = retval;
header.type = T_MKNOD;
}
break;
case T_MKDIR:
path = va_arg(ap, V9fsString *);
mode = va_arg(ap, int);
uid = va_arg(ap, int);
gid = va_arg(ap, int);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "ddsd",
uid, gid, path, mode);
if (retval > 0) {
header.size = retval;
header.type = T_MKDIR;
}
break;
case T_SYMLINK:
oldpath = va_arg(ap, V9fsString *);
path = va_arg(ap, V9fsString *);
uid = va_arg(ap, int);
gid = va_arg(ap, int);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "ddss",
uid, gid, oldpath, path);
if (retval > 0) {
header.size = retval;
header.type = T_SYMLINK;
}
break;
case T_LINK:
oldpath = va_arg(ap, V9fsString *);
path = va_arg(ap, V9fsString *);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "ss",
oldpath, path);
if (retval > 0) {
header.size = retval;
header.type = T_LINK;
}
break;
case T_LSTAT:
path = va_arg(ap, V9fsString *);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "s", path);
if (retval > 0) {
header.size = retval;
header.type = T_LSTAT;
}
break;
case T_READLINK:
path = va_arg(ap, V9fsString *);
size = va_arg(ap, int);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "sd", path, size);
if (retval > 0) {
header.size = retval;
header.type = T_READLINK;
}
break;
case T_STATFS:
path = va_arg(ap, V9fsString *);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "s", path);
if (retval > 0) {
header.size = retval;
header.type = T_STATFS;
}
break;
case T_CHMOD:
path = va_arg(ap, V9fsString *);
mode = va_arg(ap, int);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "sd", path, mode);
if (retval > 0) {
header.size = retval;
header.type = T_CHMOD;
}
break;
case T_CHOWN:
path = va_arg(ap, V9fsString *);
uid = va_arg(ap, int);
gid = va_arg(ap, int);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "sdd", path, uid, gid);
if (retval > 0) {
header.size = retval;
header.type = T_CHOWN;
}
break;
case T_TRUNCATE:
path = va_arg(ap, V9fsString *);
offset = va_arg(ap, uint64_t);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "sq", path, offset);
if (retval > 0) {
header.size = retval;
header.type = T_TRUNCATE;
}
break;
case T_UTIME:
path = va_arg(ap, V9fsString *);
spec[0].tv_sec = va_arg(ap, long);
spec[0].tv_nsec = va_arg(ap, long);
spec[1].tv_sec = va_arg(ap, long);
spec[1].tv_nsec = va_arg(ap, long);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "sqqqq", path,
spec[0].tv_sec, spec[1].tv_nsec,
spec[1].tv_sec, spec[1].tv_nsec);
if (retval > 0) {
header.size = retval;
header.type = T_UTIME;
}
break;
case T_RENAME:
oldpath = va_arg(ap, V9fsString *);
path = va_arg(ap, V9fsString *);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "ss", oldpath, path);
if (retval > 0) {
header.size = retval;
header.type = T_RENAME;
}
break;
case T_REMOVE:
path = va_arg(ap, V9fsString *);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "s", path);
if (retval > 0) {
header.size = retval;
header.type = T_REMOVE;
}
break;
case T_LGETXATTR:
size = va_arg(ap, int);
path = va_arg(ap, V9fsString *);
name = va_arg(ap, V9fsString *);
retval = proxy_marshal(iovec, PROXY_HDR_SZ,
"dss", size, path, name);
if (retval > 0) {
header.size = retval;
header.type = T_LGETXATTR;
}
break;
case T_LLISTXATTR:
size = va_arg(ap, int);
path = va_arg(ap, V9fsString *);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "ds", size, path);
if (retval > 0) {
header.size = retval;
header.type = T_LLISTXATTR;
}
break;
case T_LSETXATTR:
path = va_arg(ap, V9fsString *);
name = va_arg(ap, V9fsString *);
value = va_arg(ap, V9fsString *);
size = va_arg(ap, int);
flags = va_arg(ap, int);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "sssdd",
path, name, value, size, flags);
if (retval > 0) {
header.size = retval;
header.type = T_LSETXATTR;
}
break;
case T_LREMOVEXATTR:
path = va_arg(ap, V9fsString *);
name = va_arg(ap, V9fsString *);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "ss", path, name);
if (retval > 0) {
header.size = retval;
header.type = T_LREMOVEXATTR;
}
break;
case T_GETVERSION:
path = va_arg(ap, V9fsString *);
retval = proxy_marshal(iovec, PROXY_HDR_SZ, "s", path);
if (retval > 0) {
header.size = retval;
header.type = T_GETVERSION;
}
break;
default:
error_report("Invalid type %d", type);
retval = -EINVAL;
break;
}
va_end(ap);
if (retval < 0) {
goto err_out;
}
/* marshal the header details */
proxy_marshal(iovec, 0, "dd", header.type, header.size);
header.size += PROXY_HDR_SZ;
retval = qemu_write_full(proxy->sockfd, iovec->iov_base, header.size);
if (retval != header.size) {
goto close_error;
}
switch (type) {
case T_OPEN:
case T_CREATE:
/*
* A file descriptor is returned as response for
* T_OPEN,T_CREATE on success
*/
if (v9fs_receivefd(proxy->sockfd, &retval) < 0) {
goto close_error;
}
break;
case T_MKNOD:
case T_MKDIR:
case T_SYMLINK:
case T_LINK:
case T_CHMOD:
case T_CHOWN:
case T_RENAME:
case T_TRUNCATE:
case T_UTIME:
case T_REMOVE:
case T_LSETXATTR:
case T_LREMOVEXATTR:
if (v9fs_receive_status(proxy, reply, &retval) < 0) {
goto close_error;
}
break;
case T_LSTAT:
case T_READLINK:
case T_STATFS:
case T_GETVERSION:
if (v9fs_receive_response(proxy, type, &retval, response) < 0) {
goto close_error;
}
break;
case T_LGETXATTR:
case T_LLISTXATTR:
if (!size) {
if (v9fs_receive_status(proxy, reply, &retval) < 0) {
goto close_error;
}
} else {
if (v9fs_receive_response(proxy, type, &retval, response) < 0) {
goto close_error;
}
}
break;
}
err_out:
qemu_mutex_unlock(&proxy->mutex);
return retval;
close_error:
close(proxy->sockfd);
proxy->sockfd = -1;
qemu_mutex_unlock(&proxy->mutex);
return -EIO;
}
static int proxy_lstat(FsContext *fs_ctx, V9fsPath *fs_path, struct stat *stbuf)
{
int retval;
retval = v9fs_request(fs_ctx->private, T_LSTAT, stbuf, fs_path);
if (retval < 0) {
errno = -retval;
return -1;
}
return retval;
}
static ssize_t proxy_readlink(FsContext *fs_ctx, V9fsPath *fs_path,
char *buf, size_t bufsz)
{
int retval;
retval = v9fs_request(fs_ctx->private, T_READLINK, buf, fs_path, bufsz);
if (retval < 0) {
errno = -retval;
return -1;
}
return strlen(buf);
}
static int proxy_close(FsContext *ctx, V9fsFidOpenState *fs)
{
return close(fs->fd);
}
static int proxy_closedir(FsContext *ctx, V9fsFidOpenState *fs)
{
return closedir(fs->dir.stream);
}
static int proxy_open(FsContext *ctx, V9fsPath *fs_path,
int flags, V9fsFidOpenState *fs)
{
fs->fd = v9fs_request(ctx->private, T_OPEN, NULL, fs_path, flags);
if (fs->fd < 0) {
errno = -fs->fd;
fs->fd = -1;
}
return fs->fd;
}
static int proxy_opendir(FsContext *ctx,
V9fsPath *fs_path, V9fsFidOpenState *fs)
{
int serrno, fd;
fs->dir.stream = NULL;
fd = v9fs_request(ctx->private, T_OPEN, NULL, fs_path, O_DIRECTORY);
if (fd < 0) {
errno = -fd;
return -1;
}
fs->dir.stream = fdopendir(fd);
if (!fs->dir.stream) {
serrno = errno;
close(fd);
errno = serrno;
return -1;
}
return 0;
}
static void proxy_rewinddir(FsContext *ctx, V9fsFidOpenState *fs)
{
rewinddir(fs->dir.stream);
}
static off_t proxy_telldir(FsContext *ctx, V9fsFidOpenState *fs)
{
return telldir(fs->dir.stream);
}
static struct dirent *proxy_readdir(FsContext *ctx, V9fsFidOpenState *fs)
{
return readdir(fs->dir.stream);
}
static void proxy_seekdir(FsContext *ctx, V9fsFidOpenState *fs, off_t off)
{
seekdir(fs->dir.stream, off);
}
static ssize_t proxy_preadv(FsContext *ctx, V9fsFidOpenState *fs,
const struct iovec *iov,
int iovcnt, off_t offset)
{
ssize_t ret;
#ifdef CONFIG_PREADV
ret = preadv(fs->fd, iov, iovcnt, offset);
#else
ret = lseek(fs->fd, offset, SEEK_SET);
if (ret >= 0) {
ret = readv(fs->fd, iov, iovcnt);
}
#endif
return ret;
}
static ssize_t proxy_pwritev(FsContext *ctx, V9fsFidOpenState *fs,
const struct iovec *iov,
int iovcnt, off_t offset)
{
ssize_t ret;
#ifdef CONFIG_PREADV
ret = pwritev(fs->fd, iov, iovcnt, offset);
#else
ret = lseek(fs->fd, offset, SEEK_SET);
if (ret >= 0) {
ret = writev(fs->fd, iov, iovcnt);
}
#endif
#ifdef CONFIG_SYNC_FILE_RANGE
if (ret > 0 && ctx->export_flags & V9FS_IMMEDIATE_WRITEOUT) {
/*
* Initiate a writeback. This is not a data integrity sync.
* We want to ensure that we don't leave dirty pages in the cache
* after write when writeout=immediate is sepcified.
*/
sync_file_range(fs->fd, offset, ret,
SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE);
}
#endif
return ret;
}
static int proxy_chmod(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp)
{
int retval;
retval = v9fs_request(fs_ctx->private, T_CHMOD, NULL, fs_path,
credp->fc_mode);
if (retval < 0) {
errno = -retval;
}
return retval;
}
static int proxy_mknod(FsContext *fs_ctx, V9fsPath *dir_path,
const char *name, FsCred *credp)
{
int retval;
V9fsString fullname;
v9fs_string_init(&fullname);
v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name);
retval = v9fs_request(fs_ctx->private, T_MKNOD, NULL, &fullname,
credp->fc_mode, credp->fc_rdev,
credp->fc_uid, credp->fc_gid);
v9fs_string_free(&fullname);
if (retval < 0) {
errno = -retval;
retval = -1;
}
return retval;
}
static int proxy_mkdir(FsContext *fs_ctx, V9fsPath *dir_path,
const char *name, FsCred *credp)
{
int retval;
V9fsString fullname;
v9fs_string_init(&fullname);
v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name);
retval = v9fs_request(fs_ctx->private, T_MKDIR, NULL, &fullname,
credp->fc_mode, credp->fc_uid, credp->fc_gid);
v9fs_string_free(&fullname);
if (retval < 0) {
errno = -retval;
retval = -1;
}
return retval;
}
static int proxy_fstat(FsContext *fs_ctx, int fid_type,
V9fsFidOpenState *fs, struct stat *stbuf)
{
int fd;
if (fid_type == P9_FID_DIR) {
fd = dirfd(fs->dir.stream);
} else {
fd = fs->fd;
}
return fstat(fd, stbuf);
}
static int proxy_open2(FsContext *fs_ctx, V9fsPath *dir_path, const char *name,
int flags, FsCred *credp, V9fsFidOpenState *fs)
{
V9fsString fullname;
v9fs_string_init(&fullname);
v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name);
fs->fd = v9fs_request(fs_ctx->private, T_CREATE, NULL, &fullname, flags,
credp->fc_mode, credp->fc_uid, credp->fc_gid);
v9fs_string_free(&fullname);
if (fs->fd < 0) {
errno = -fs->fd;
fs->fd = -1;
}
return fs->fd;
}
static int proxy_symlink(FsContext *fs_ctx, const char *oldpath,
V9fsPath *dir_path, const char *name, FsCred *credp)
{
int retval;
V9fsString fullname, target;
v9fs_string_init(&fullname);
v9fs_string_init(&target);
v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name);
v9fs_string_sprintf(&target, "%s", oldpath);
retval = v9fs_request(fs_ctx->private, T_SYMLINK, NULL, &target, &fullname,
credp->fc_uid, credp->fc_gid);
v9fs_string_free(&fullname);
v9fs_string_free(&target);
if (retval < 0) {
errno = -retval;
retval = -1;
}
return retval;
}
static int proxy_link(FsContext *ctx, V9fsPath *oldpath,
V9fsPath *dirpath, const char *name)
{
int retval;
V9fsString newpath;
v9fs_string_init(&newpath);
v9fs_string_sprintf(&newpath, "%s/%s", dirpath->data, name);
retval = v9fs_request(ctx->private, T_LINK, NULL, oldpath, &newpath);
v9fs_string_free(&newpath);
if (retval < 0) {
errno = -retval;
retval = -1;
}
return retval;
}
static int proxy_truncate(FsContext *ctx, V9fsPath *fs_path, off_t size)
{
int retval;
retval = v9fs_request(ctx->private, T_TRUNCATE, NULL, fs_path, size);
if (retval < 0) {
errno = -retval;
return -1;
}
return 0;
}
static int proxy_rename(FsContext *ctx, const char *oldpath,
const char *newpath)
{
int retval;
V9fsString oldname, newname;
v9fs_string_init(&oldname);
v9fs_string_init(&newname);
v9fs_string_sprintf(&oldname, "%s", oldpath);
v9fs_string_sprintf(&newname, "%s", newpath);
retval = v9fs_request(ctx->private, T_RENAME, NULL, &oldname, &newname);
v9fs_string_free(&oldname);
v9fs_string_free(&newname);
if (retval < 0) {
errno = -retval;
}
return retval;
}
static int proxy_chown(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp)
{
int retval;
retval = v9fs_request(fs_ctx->private, T_CHOWN, NULL, fs_path,
credp->fc_uid, credp->fc_gid);
if (retval < 0) {
errno = -retval;
}
return retval;
}
static int proxy_utimensat(FsContext *s, V9fsPath *fs_path,
const struct timespec *buf)
{
int retval;
retval = v9fs_request(s->private, T_UTIME, NULL, fs_path,
buf[0].tv_sec, buf[0].tv_nsec,
buf[1].tv_sec, buf[1].tv_nsec);
if (retval < 0) {
errno = -retval;
}
return retval;
}
static int proxy_remove(FsContext *ctx, const char *path)
{
int retval;
V9fsString name;
v9fs_string_init(&name);
v9fs_string_sprintf(&name, "%s", path);
retval = v9fs_request(ctx->private, T_REMOVE, NULL, &name);
v9fs_string_free(&name);
if (retval < 0) {
errno = -retval;
}
return retval;
}
static int proxy_fsync(FsContext *ctx, int fid_type,
V9fsFidOpenState *fs, int datasync)
{
int fd;
if (fid_type == P9_FID_DIR) {
fd = dirfd(fs->dir.stream);
} else {
fd = fs->fd;
}
if (datasync) {
return qemu_fdatasync(fd);
} else {
return fsync(fd);
}
}
static int proxy_statfs(FsContext *s, V9fsPath *fs_path, struct statfs *stbuf)
{
int retval;
retval = v9fs_request(s->private, T_STATFS, stbuf, fs_path);
if (retval < 0) {
errno = -retval;
return -1;
}
return retval;
}
static ssize_t proxy_lgetxattr(FsContext *ctx, V9fsPath *fs_path,
const char *name, void *value, size_t size)
{
int retval;
V9fsString xname;
v9fs_string_init(&xname);
v9fs_string_sprintf(&xname, "%s", name);
retval = v9fs_request(ctx->private, T_LGETXATTR, value, size, fs_path,
&xname);
v9fs_string_free(&xname);
if (retval < 0) {
errno = -retval;
}
return retval;
}
static ssize_t proxy_llistxattr(FsContext *ctx, V9fsPath *fs_path,
void *value, size_t size)
{
int retval;
retval = v9fs_request(ctx->private, T_LLISTXATTR, value, size, fs_path);
if (retval < 0) {
errno = -retval;
}
return retval;
}
static int proxy_lsetxattr(FsContext *ctx, V9fsPath *fs_path, const char *name,
void *value, size_t size, int flags)
{
int retval;
V9fsString xname, xvalue;
v9fs_string_init(&xname);
v9fs_string_sprintf(&xname, "%s", name);
v9fs_string_init(&xvalue);
xvalue.size = size;
xvalue.data = g_malloc(size);
memcpy(xvalue.data, value, size);
retval = v9fs_request(ctx->private, T_LSETXATTR, value, fs_path, &xname,
&xvalue, size, flags);
v9fs_string_free(&xname);
v9fs_string_free(&xvalue);
if (retval < 0) {
errno = -retval;
}
return retval;
}
static int proxy_lremovexattr(FsContext *ctx, V9fsPath *fs_path,
const char *name)
{
int retval;
V9fsString xname;
v9fs_string_init(&xname);
v9fs_string_sprintf(&xname, "%s", name);
retval = v9fs_request(ctx->private, T_LREMOVEXATTR, NULL, fs_path, &xname);
v9fs_string_free(&xname);
if (retval < 0) {
errno = -retval;
}
return retval;
}
static int proxy_name_to_path(FsContext *ctx, V9fsPath *dir_path,
const char *name, V9fsPath *target)
{
if (dir_path) {
v9fs_path_sprintf(target, "%s/%s", dir_path->data, name);
} else {
v9fs_path_sprintf(target, "%s", name);
}
return 0;
}
static int proxy_renameat(FsContext *ctx, V9fsPath *olddir,
const char *old_name, V9fsPath *newdir,
const char *new_name)
{
int ret;
V9fsString old_full_name, new_full_name;
v9fs_string_init(&old_full_name);
v9fs_string_init(&new_full_name);
v9fs_string_sprintf(&old_full_name, "%s/%s", olddir->data, old_name);
v9fs_string_sprintf(&new_full_name, "%s/%s", newdir->data, new_name);
ret = proxy_rename(ctx, old_full_name.data, new_full_name.data);
v9fs_string_free(&old_full_name);
v9fs_string_free(&new_full_name);
return ret;
}
static int proxy_unlinkat(FsContext *ctx, V9fsPath *dir,
const char *name, int flags)
{
int ret;
V9fsString fullname;
v9fs_string_init(&fullname);
v9fs_string_sprintf(&fullname, "%s/%s", dir->data, name);
ret = proxy_remove(ctx, fullname.data);
v9fs_string_free(&fullname);
return ret;
}
static int proxy_ioc_getversion(FsContext *fs_ctx, V9fsPath *path,
mode_t st_mode, uint64_t *st_gen)
{
int err;
/* Do not try to open special files like device nodes, fifos etc
* we can get fd for regular files and directories only
*/
if (!S_ISREG(st_mode) && !S_ISDIR(st_mode)) {
errno = ENOTTY;
return -1;
}
err = v9fs_request(fs_ctx->private, T_GETVERSION, st_gen, path);
if (err < 0) {
errno = -err;
err = -1;
}
return err;
}
static int connect_namedsocket(const char *path, Error **errp)
{
int sockfd, size;
struct sockaddr_un helper;
if (strlen(path) >= sizeof(helper.sun_path)) {
error_setg(errp, "socket name too long");
return -1;
}
sockfd = socket(AF_UNIX, SOCK_STREAM, 0);
if (sockfd < 0) {
error_setg_errno(errp, errno, "failed to create client socket");
return -1;
}
strcpy(helper.sun_path, path);
helper.sun_family = AF_UNIX;
size = strlen(helper.sun_path) + sizeof(helper.sun_family);
if (connect(sockfd, (struct sockaddr *)&helper, size) < 0) {
error_setg_errno(errp, errno, "failed to connect to '%s'", path);
close(sockfd);
return -1;
}
/* remove the socket for security reasons */
unlink(path);
return sockfd;
}
static void error_append_socket_sockfd_hint(Error **errp)
{
error_append_hint(errp, "Either specify socket=/some/path where /some/path"
" points to a listening AF_UNIX socket or sock_fd=fd"
" where fd is a file descriptor to a connected AF_UNIX"
" socket\n");
}
static int proxy_parse_opts(QemuOpts *opts, FsDriverEntry *fs, Error **errp)
{
const char *socket = qemu_opt_get(opts, "socket");
const char *sock_fd = qemu_opt_get(opts, "sock_fd");
if (!socket && !sock_fd) {
error_setg(errp, "both socket and sock_fd properties are missing");
error_append_socket_sockfd_hint(errp);
return -1;
}
if (socket && sock_fd) {
error_setg(errp, "both socket and sock_fd properties are set");
error_append_socket_sockfd_hint(errp);
return -1;
}
if (socket) {
fs->path = g_strdup(socket);
fs->export_flags = V9FS_PROXY_SOCK_NAME;
} else {
fs->path = g_strdup(sock_fd);
fs->export_flags = V9FS_PROXY_SOCK_FD;
}
return 0;
}
static int proxy_init(FsContext *ctx, Error **errp)
{
V9fsProxy *proxy = g_malloc(sizeof(V9fsProxy));
int sock_id;
if (ctx->export_flags & V9FS_PROXY_SOCK_NAME) {
sock_id = connect_namedsocket(ctx->fs_root, errp);
} else {
sock_id = atoi(ctx->fs_root);
if (sock_id < 0) {
error_setg(errp, "socket descriptor not initialized");
}
}
if (sock_id < 0) {
g_free(proxy);
return -1;
}
g_free(ctx->fs_root);
ctx->fs_root = NULL;
proxy->in_iovec.iov_base = g_malloc(PROXY_MAX_IO_SZ + PROXY_HDR_SZ);
proxy->in_iovec.iov_len = PROXY_MAX_IO_SZ + PROXY_HDR_SZ;
proxy->out_iovec.iov_base = g_malloc(PROXY_MAX_IO_SZ + PROXY_HDR_SZ);
proxy->out_iovec.iov_len = PROXY_MAX_IO_SZ + PROXY_HDR_SZ;
ctx->private = proxy;
proxy->sockfd = sock_id;
qemu_mutex_init(&proxy->mutex);
ctx->export_flags |= V9FS_PATHNAME_FSCONTEXT;
ctx->exops.get_st_gen = proxy_ioc_getversion;
return 0;
}
static void proxy_cleanup(FsContext *ctx)
{
V9fsProxy *proxy = ctx->private;
g_free(proxy->out_iovec.iov_base);
g_free(proxy->in_iovec.iov_base);
if (ctx->export_flags & V9FS_PROXY_SOCK_NAME) {
close(proxy->sockfd);
}
g_free(proxy);
}
FileOperations proxy_ops = {
.parse_opts = proxy_parse_opts,
.init = proxy_init,
.cleanup = proxy_cleanup,
.lstat = proxy_lstat,
.readlink = proxy_readlink,
.close = proxy_close,
.closedir = proxy_closedir,
.open = proxy_open,
.opendir = proxy_opendir,
.rewinddir = proxy_rewinddir,
.telldir = proxy_telldir,
.readdir = proxy_readdir,
.seekdir = proxy_seekdir,
.preadv = proxy_preadv,
.pwritev = proxy_pwritev,
.chmod = proxy_chmod,
.mknod = proxy_mknod,
.mkdir = proxy_mkdir,
.fstat = proxy_fstat,
.open2 = proxy_open2,
.symlink = proxy_symlink,
.link = proxy_link,
.truncate = proxy_truncate,
.rename = proxy_rename,
.chown = proxy_chown,
.utimensat = proxy_utimensat,
.remove = proxy_remove,
.fsync = proxy_fsync,
.statfs = proxy_statfs,
.lgetxattr = proxy_lgetxattr,
.llistxattr = proxy_llistxattr,
.lsetxattr = proxy_lsetxattr,
.lremovexattr = proxy_lremovexattr,
.name_to_path = proxy_name_to_path,
.renameat = proxy_renameat,
.unlinkat = proxy_unlinkat,
};