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authorH. Peter Anvin <hpa@linux.intel.com>2013-06-28 15:26:17 -0700
committerH. Peter Anvin <hpa@linux.intel.com>2013-06-28 15:26:17 -0700
commit9f84b6267ccde1bebe3f9cd40a91716b5ece5e20 (patch)
treeb51dcf9fb1b7205ed8134ad1169e73719897163d /lib/iovec.c
parent719038de98bc8479b771c582a1e4a1e86079da22 (diff)
parent5f8c4218148822fde6eebbeefc34bd0a6061e031 (diff)
Merge remote-tracking branch 'origin/x86/fpu' into queue/x86/cpu
Use the union of 3.10 x86/cpu and x86/fpu as baseline. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'lib/iovec.c')
-rw-r--r--lib/iovec.c53
1 files changed, 53 insertions, 0 deletions
diff --git a/lib/iovec.c b/lib/iovec.c
new file mode 100644
index 00000000000..454baa88bf2
--- /dev/null
+++ b/lib/iovec.c
@@ -0,0 +1,53 @@
+#include <linux/uaccess.h>
+#include <linux/export.h>
+#include <linux/uio.h>
+
+/*
+ * Copy iovec to kernel. Returns -EFAULT on error.
+ *
+ * Note: this modifies the original iovec.
+ */
+
+int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len)
+{
+ while (len > 0) {
+ if (iov->iov_len) {
+ int copy = min_t(unsigned int, len, iov->iov_len);
+ if (copy_from_user(kdata, iov->iov_base, copy))
+ return -EFAULT;
+ len -= copy;
+ kdata += copy;
+ iov->iov_base += copy;
+ iov->iov_len -= copy;
+ }
+ iov++;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(memcpy_fromiovec);
+
+/*
+ * Copy kernel to iovec. Returns -EFAULT on error.
+ *
+ * Note: this modifies the original iovec.
+ */
+
+int memcpy_toiovec(struct iovec *iov, unsigned char *kdata, int len)
+{
+ while (len > 0) {
+ if (iov->iov_len) {
+ int copy = min_t(unsigned int, iov->iov_len, len);
+ if (copy_to_user(iov->iov_base, kdata, copy))
+ return -EFAULT;
+ kdata += copy;
+ len -= copy;
+ iov->iov_len -= copy;
+ iov->iov_base += copy;
+ }
+ iov++;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(memcpy_toiovec);