* For lack of a better implementation, implement vmsplice() to userspace
* as a simple copy of the pipes pages to the user iov.
*/
-static long vmsplice_to_user(struct file *file, const struct iovec __user *uiov,
- unsigned long nr_segs, unsigned int flags)
+static long vmsplice_to_user(struct file *file, struct iov_iter *iter,
+ unsigned int flags)
{
- struct pipe_inode_info *pipe;
- struct splice_desc sd;
- long ret;
- struct iovec iovstack[UIO_FASTIOV];
- struct iovec *iov = iovstack;
- struct iov_iter iter;
+ struct pipe_inode_info *pipe = get_pipe_info(file);
+ struct splice_desc sd = {
+ .total_len = iov_iter_count(iter),
+ .flags = flags,
+ .u.data = iter
+ };
+ long ret = 0;
- pipe = get_pipe_info(file);
if (!pipe)
return -EBADF;
- ret = import_iovec(READ, uiov, nr_segs,
- ARRAY_SIZE(iovstack), &iov, &iter);
- if (ret < 0)
- return ret;
-
- sd.total_len = iov_iter_count(&iter);
- sd.len = 0;
- sd.flags = flags;
- sd.u.data = &iter;
- sd.pos = 0;
-
if (sd.total_len) {
pipe_lock(pipe);
ret = __splice_from_pipe(pipe, &sd, pipe_to_user);
pipe_unlock(pipe);
}
- kfree(iov);
return ret;
}
* as splice-from-memory, where the regular splice is splice-from-file (or
* to file). In both cases the output is a pipe, naturally.
*/
-static long vmsplice_to_pipe(struct file *file, const struct iovec __user *uiov,
- unsigned long nr_segs, unsigned int flags)
+static long vmsplice_to_pipe(struct file *file, struct iov_iter *iter,
+ unsigned int flags)
{
struct pipe_inode_info *pipe;
- struct iovec iovstack[UIO_FASTIOV];
- struct iovec *iov = iovstack;
- struct iov_iter from;
- long ret;
+ long ret = 0;
unsigned buf_flag = 0;
if (flags & SPLICE_F_GIFT)
if (!pipe)
return -EBADF;
- ret = import_iovec(WRITE, uiov, nr_segs,
- ARRAY_SIZE(iovstack), &iov, &from);
- if (ret < 0)
- return ret;
-
pipe_lock(pipe);
ret = wait_for_space(pipe, flags);
if (!ret)
- ret = iter_to_pipe(&from, pipe, buf_flag);
+ ret = iter_to_pipe(iter, pipe, buf_flag);
pipe_unlock(pipe);
if (ret > 0)
wakeup_pipe_readers(pipe);
- kfree(iov);
return ret;
}
+static int vmsplice_type(struct fd f, int *type)
+{
+ if (!f.file)
+ return -EBADF;
+ if (f.file->f_mode & FMODE_WRITE) {
+ *type = WRITE;
+ } else if (f.file->f_mode & FMODE_READ) {
+ *type = READ;
+ } else {
+ fdput(f);
+ return -EBADF;
+ }
+ return 0;
+}
+
/*
* Note that vmsplice only really supports true splicing _from_ user memory
* to a pipe, not the other way around. Splicing from user memory is a simple
* Currently we punt and implement it as a normal copy, see pipe_to_user().
*
*/
-static long do_vmsplice(int fd, const struct iovec __user *iov,
- unsigned long nr_segs, unsigned int flags)
+static long do_vmsplice(struct file *f, struct iov_iter *iter, unsigned int flags)
{
- struct fd f;
- long error;
-
if (unlikely(flags & ~SPLICE_F_ALL))
return -EINVAL;
- if (unlikely(nr_segs > UIO_MAXIOV))
- return -EINVAL;
- else if (unlikely(!nr_segs))
- return 0;
- error = -EBADF;
- f = fdget(fd);
- if (f.file) {
- if (f.file->f_mode & FMODE_WRITE)
- error = vmsplice_to_pipe(f.file, iov, nr_segs, flags);
- else if (f.file->f_mode & FMODE_READ)
- error = vmsplice_to_user(f.file, iov, nr_segs, flags);
-
- fdput(f);
- }
+ if (!iov_iter_count(iter))
+ return 0;
- return error;
+ if (iov_iter_rw(iter) == WRITE)
+ return vmsplice_to_pipe(f, iter, flags);
+ else
+ return vmsplice_to_user(f, iter, flags);
}
-SYSCALL_DEFINE4(vmsplice, int, fd, const struct iovec __user *, iov,
+SYSCALL_DEFINE4(vmsplice, int, fd, const struct iovec __user *, uiov,
unsigned long, nr_segs, unsigned int, flags)
{
- return do_vmsplice(fd, iov, nr_segs, flags);
+ struct iovec iovstack[UIO_FASTIOV];
+ struct iovec *iov = iovstack;
+ struct iov_iter iter;
+ long error;
+ struct fd f;
+ int type;
+
+ f = fdget(fd);
+ error = vmsplice_type(f, &type);
+ if (error)
+ return error;
+
+ error = import_iovec(type, uiov, nr_segs,
+ ARRAY_SIZE(iovstack), &iov, &iter);
+ if (!error) {
+ error = do_vmsplice(f.file, &iter, flags);
+ kfree(iov);
+ }
+ fdput(f);
+ return error;
}
#ifdef CONFIG_COMPAT
COMPAT_SYSCALL_DEFINE4(vmsplice, int, fd, const struct compat_iovec __user *, iov32,
unsigned int, nr_segs, unsigned int, flags)
{
- unsigned i;
- struct iovec __user *iov;
- if (nr_segs > UIO_MAXIOV)
- return -EINVAL;
- iov = compat_alloc_user_space(nr_segs * sizeof(struct iovec));
- for (i = 0; i < nr_segs; i++) {
- struct compat_iovec v;
- if (get_user(v.iov_base, &iov32[i].iov_base) ||
- get_user(v.iov_len, &iov32[i].iov_len) ||
- put_user(compat_ptr(v.iov_base), &iov[i].iov_base) ||
- put_user(v.iov_len, &iov[i].iov_len))
- return -EFAULT;
+ struct iovec iovstack[UIO_FASTIOV];
+ struct iovec *iov = iovstack;
+ struct iov_iter iter;
+ long error;
+ struct fd f;
+ int type;
+
+ f = fdget(fd);
+ error = vmsplice_type(f, &type);
+ if (error)
+ return error;
+
+ error = compat_import_iovec(type, iov32, nr_segs,
+ ARRAY_SIZE(iovstack), &iov, &iter);
+ if (!error) {
+ error = do_vmsplice(f.file, &iter, flags);
+ kfree(iov);
}
- return do_vmsplice(fd, iov, nr_segs, flags);
+ fdput(f);
+ return error;
}
#endif
git.samba.org / sfrench / cifs-2.6.git / blobdiff