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Diffstat (limited to 'fs/pipe.c')
-rw-r--r--fs/pipe.c55
1 files changed, 32 insertions, 23 deletions
diff --git a/fs/pipe.c b/fs/pipe.c
index 78fd0d0788db..46f1ab264a4c 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -117,25 +117,27 @@ void pipe_wait(struct pipe_inode_info *pipe)
}
static int
-pipe_iov_copy_from_user(void *to, struct iovec *iov, unsigned long len,
- int atomic)
+pipe_iov_copy_from_user(void *addr, int *offset, struct iovec *iov,
+ size_t *remaining, int atomic)
{
unsigned long copy;
- while (len > 0) {
+ while (*remaining > 0) {
while (!iov->iov_len)
iov++;
- copy = min_t(unsigned long, len, iov->iov_len);
+ copy = min_t(unsigned long, *remaining, iov->iov_len);
if (atomic) {
- if (__copy_from_user_inatomic(to, iov->iov_base, copy))
+ if (__copy_from_user_inatomic(addr + *offset,
+ iov->iov_base, copy))
return -EFAULT;
} else {
- if (copy_from_user(to, iov->iov_base, copy))
+ if (copy_from_user(addr + *offset,
+ iov->iov_base, copy))
return -EFAULT;
}
- to += copy;
- len -= copy;
+ *offset += copy;
+ *remaining -= copy;
iov->iov_base += copy;
iov->iov_len -= copy;
}
@@ -143,25 +145,27 @@ pipe_iov_copy_from_user(void *to, struct iovec *iov, unsigned long len,
}
static int
-pipe_iov_copy_to_user(struct iovec *iov, const void *from, unsigned long len,
- int atomic)
+pipe_iov_copy_to_user(struct iovec *iov, void *addr, int *offset,
+ size_t *remaining, int atomic)
{
unsigned long copy;
- while (len > 0) {
+ while (*remaining > 0) {
while (!iov->iov_len)
iov++;
- copy = min_t(unsigned long, len, iov->iov_len);
+ copy = min_t(unsigned long, *remaining, iov->iov_len);
if (atomic) {
- if (__copy_to_user_inatomic(iov->iov_base, from, copy))
+ if (__copy_to_user_inatomic(iov->iov_base,
+ addr + *offset, copy))
return -EFAULT;
} else {
- if (copy_to_user(iov->iov_base, from, copy))
+ if (copy_to_user(iov->iov_base,
+ addr + *offset, copy))
return -EFAULT;
}
- from += copy;
- len -= copy;
+ *offset += copy;
+ *remaining -= copy;
iov->iov_base += copy;
iov->iov_len -= copy;
}
@@ -395,7 +399,7 @@ pipe_read(struct kiocb *iocb, const struct iovec *_iov,
struct pipe_buffer *buf = pipe->bufs + curbuf;
const struct pipe_buf_operations *ops = buf->ops;
void *addr;
- size_t chars = buf->len;
+ size_t chars = buf->len, remaining;
int error, atomic;
if (chars > total_len)
@@ -409,9 +413,11 @@ pipe_read(struct kiocb *iocb, const struct iovec *_iov,
}
atomic = !iov_fault_in_pages_write(iov, chars);
+ remaining = chars;
redo:
addr = ops->map(pipe, buf, atomic);
- error = pipe_iov_copy_to_user(iov, addr + buf->offset, chars, atomic);
+ error = pipe_iov_copy_to_user(iov, addr, &buf->offset,
+ &remaining, atomic);
ops->unmap(pipe, buf, addr);
if (unlikely(error)) {
/*
@@ -426,7 +432,6 @@ redo:
break;
}
ret += chars;
- buf->offset += chars;
buf->len -= chars;
/* Was it a packet buffer? Clean up and exit */
@@ -531,6 +536,7 @@ pipe_write(struct kiocb *iocb, const struct iovec *_iov,
if (ops->can_merge && offset + chars <= PAGE_SIZE) {
int error, atomic = 1;
void *addr;
+ size_t remaining = chars;
error = ops->confirm(pipe, buf);
if (error)
@@ -539,8 +545,8 @@ pipe_write(struct kiocb *iocb, const struct iovec *_iov,
iov_fault_in_pages_read(iov, chars);
redo1:
addr = ops->map(pipe, buf, atomic);
- error = pipe_iov_copy_from_user(offset + addr, iov,
- chars, atomic);
+ error = pipe_iov_copy_from_user(addr, &offset, iov,
+ &remaining, atomic);
ops->unmap(pipe, buf, addr);
ret = error;
do_wakeup = 1;
@@ -575,6 +581,8 @@ redo1:
struct page *page = pipe->tmp_page;
char *src;
int error, atomic = 1;
+ int offset = 0;
+ size_t remaining;
if (!page) {
page = alloc_page(GFP_HIGHUSER);
@@ -595,14 +603,15 @@ redo1:
chars = total_len;
iov_fault_in_pages_read(iov, chars);
+ remaining = chars;
redo2:
if (atomic)
src = kmap_atomic(page);
else
src = kmap(page);
- error = pipe_iov_copy_from_user(src, iov, chars,
- atomic);
+ error = pipe_iov_copy_from_user(src, &offset, iov,
+ &remaining, atomic);
if (atomic)
kunmap_atomic(src);
else