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authorDmitry Torokhov <dmitry.torokhov@gmail.com>2017-05-29 19:54:21 -0700
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2017-05-29 19:54:21 -0700
commitd8f797c60661a90ee26ca9330cf85ede9aa2ec17 (patch)
tree5038609885fc3e4cb7f329d974875ac4411c6af5 /lib/iov_iter.c
parentInput: tsc2007 - move header file out of I2C realm (diff)
parentLinux 4.12-rc3 (diff)
downloadwireguard-linux-d8f797c60661a90ee26ca9330cf85ede9aa2ec17.tar.xz
wireguard-linux-d8f797c60661a90ee26ca9330cf85ede9aa2ec17.zip
Merge tag 'v4.12-rc3' into next
Sync with mainline to bring in changes in platform drovers dropping calls to sparse_keymap_free() so that we can remove it for good.
Diffstat (limited to 'lib/iov_iter.c')
-rw-r--r--lib/iov_iter.c76
1 files changed, 69 insertions, 7 deletions
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index e68604ae3ced..f835964c9485 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -413,7 +413,7 @@ void iov_iter_init(struct iov_iter *i, int direction,
size_t count)
{
/* It will get better. Eventually... */
- if (segment_eq(get_fs(), KERNEL_DS)) {
+ if (uaccess_kernel()) {
direction |= ITER_KVEC;
i->type = direction;
i->kvec = (struct kvec *)iov;
@@ -604,7 +604,7 @@ size_t copy_from_iter_nocache(void *addr, size_t bytes, struct iov_iter *i)
return 0;
}
iterate_and_advance(i, bytes, v,
- __copy_from_user_nocache((to += v.iov_len) - v.iov_len,
+ __copy_from_user_inatomic_nocache((to += v.iov_len) - v.iov_len,
v.iov_base, v.iov_len),
memcpy_from_page((to += v.bv_len) - v.bv_len, v.bv_page,
v.bv_offset, v.bv_len),
@@ -625,7 +625,7 @@ bool copy_from_iter_full_nocache(void *addr, size_t bytes, struct iov_iter *i)
if (unlikely(i->count < bytes))
return false;
iterate_all_kinds(i, bytes, v, ({
- if (__copy_from_user_nocache((to += v.iov_len) - v.iov_len,
+ if (__copy_from_user_inatomic_nocache((to += v.iov_len) - v.iov_len,
v.iov_base, v.iov_len))
return false;
0;}),
@@ -786,6 +786,70 @@ void iov_iter_advance(struct iov_iter *i, size_t size)
}
EXPORT_SYMBOL(iov_iter_advance);
+void iov_iter_revert(struct iov_iter *i, size_t unroll)
+{
+ if (!unroll)
+ return;
+ if (WARN_ON(unroll > MAX_RW_COUNT))
+ return;
+ i->count += unroll;
+ if (unlikely(i->type & ITER_PIPE)) {
+ struct pipe_inode_info *pipe = i->pipe;
+ int idx = i->idx;
+ size_t off = i->iov_offset;
+ while (1) {
+ size_t n = off - pipe->bufs[idx].offset;
+ if (unroll < n) {
+ off -= unroll;
+ break;
+ }
+ unroll -= n;
+ if (!unroll && idx == i->start_idx) {
+ off = 0;
+ break;
+ }
+ if (!idx--)
+ idx = pipe->buffers - 1;
+ off = pipe->bufs[idx].offset + pipe->bufs[idx].len;
+ }
+ i->iov_offset = off;
+ i->idx = idx;
+ pipe_truncate(i);
+ return;
+ }
+ if (unroll <= i->iov_offset) {
+ i->iov_offset -= unroll;
+ return;
+ }
+ unroll -= i->iov_offset;
+ if (i->type & ITER_BVEC) {
+ const struct bio_vec *bvec = i->bvec;
+ while (1) {
+ size_t n = (--bvec)->bv_len;
+ i->nr_segs++;
+ if (unroll <= n) {
+ i->bvec = bvec;
+ i->iov_offset = n - unroll;
+ return;
+ }
+ unroll -= n;
+ }
+ } else { /* same logics for iovec and kvec */
+ const struct iovec *iov = i->iov;
+ while (1) {
+ size_t n = (--iov)->iov_len;
+ i->nr_segs++;
+ if (unroll <= n) {
+ i->iov = iov;
+ i->iov_offset = n - unroll;
+ return;
+ }
+ unroll -= n;
+ }
+ }
+}
+EXPORT_SYMBOL(iov_iter_revert);
+
/*
* Return the count of just the current iov_iter segment.
*/
@@ -839,6 +903,7 @@ void iov_iter_pipe(struct iov_iter *i, int direction,
i->idx = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1);
i->iov_offset = 0;
i->count = count;
+ i->start_idx = i->idx;
}
EXPORT_SYMBOL(iov_iter_pipe);
@@ -965,10 +1030,7 @@ EXPORT_SYMBOL(iov_iter_get_pages);
static struct page **get_pages_array(size_t n)
{
- struct page **p = kmalloc(n * sizeof(struct page *), GFP_KERNEL);
- if (!p)
- p = vmalloc(n * sizeof(struct page *));
- return p;
+ return kvmalloc_array(n, sizeof(struct page *), GFP_KERNEL);
}
static ssize_t pipe_get_pages_alloc(struct iov_iter *i,