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authorDaniel Vetter <daniel.vetter@ffwll.ch>2014-07-07 10:17:56 +0200
committerDaniel Vetter <daniel.vetter@ffwll.ch>2014-07-07 10:17:56 +0200
commitf1615bbe9be4def59c3b3eaddb60722efeed16c2 (patch)
treeca3020e65447576fc1826e819651e6ba072030b5 /lib/iovec.c
parentcfb3c0ab0903abb6ea5215b37eebd9c2a1f057eb (diff)
parentcd3de83f147601356395b57a8673e9c5ff1e59d1 (diff)
Merge tag 'v3.16-rc4' into drm-intel-next-queued
Due to Dave's vacation drm-next hasn't opened yet for 3.17 so I couldn't move my drm-intel-next queue forward yet like I usually do. Just pull in the latest upstream -rc to unblock patch merging - I don't want to needlessly rebase my current patch pile really and void all the testing we've done already. Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'lib/iovec.c')
-rw-r--r--lib/iovec.c55
1 files changed, 55 insertions, 0 deletions
diff --git a/lib/iovec.c b/lib/iovec.c
index 454baa88bf2..7a7c2da4cdd 100644
--- a/lib/iovec.c
+++ b/lib/iovec.c
@@ -51,3 +51,58 @@ int memcpy_toiovec(struct iovec *iov, unsigned char *kdata, int len)
return 0;
}
EXPORT_SYMBOL(memcpy_toiovec);
+
+/*
+ * Copy kernel to iovec. Returns -EFAULT on error.
+ */
+
+int memcpy_toiovecend(const struct iovec *iov, unsigned char *kdata,
+ int offset, int len)
+{
+ int copy;
+ for (; len > 0; ++iov) {
+ /* Skip over the finished iovecs */
+ if (unlikely(offset >= iov->iov_len)) {
+ offset -= iov->iov_len;
+ continue;
+ }
+ copy = min_t(unsigned int, iov->iov_len - offset, len);
+ if (copy_to_user(iov->iov_base + offset, kdata, copy))
+ return -EFAULT;
+ offset = 0;
+ kdata += copy;
+ len -= copy;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(memcpy_toiovecend);
+
+/*
+ * Copy iovec to kernel. Returns -EFAULT on error.
+ */
+
+int memcpy_fromiovecend(unsigned char *kdata, const struct iovec *iov,
+ int offset, int len)
+{
+ /* Skip over the finished iovecs */
+ while (offset >= iov->iov_len) {
+ offset -= iov->iov_len;
+ iov++;
+ }
+
+ while (len > 0) {
+ u8 __user *base = iov->iov_base + offset;
+ int copy = min_t(unsigned int, len, iov->iov_len - offset);
+
+ offset = 0;
+ if (copy_from_user(kdata, base, copy))
+ return -EFAULT;
+ len -= copy;
+ kdata += copy;
+ iov++;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(memcpy_fromiovecend);