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authorMichael S. Tsirkin <mst@redhat.com>2014-06-19 21:22:56 +0300
committerNicholas Bellinger <nab@linux-iscsi.org>2014-06-27 11:47:58 -0700
commitac5ccdba3a1659b3517e7e99ef7d35a6a2d77cf4 (patch)
treecbbec5559a3cb50e47c73494a9f256155a284efe /lib
parent97c99b47ac58bacb7c09e1f47d5d184434f6b06a (diff)
iovec: move memcpy_from/toiovecend to lib/iovec.c
ERROR: "memcpy_fromiovecend" [drivers/vhost/vhost_scsi.ko] undefined! commit 9f977ef7b671f6169eca78bf40f230fe84b7c7e5 vhost-scsi: Include prot_bytes into expected data transfer length in target-pending makes drivers/vhost/scsi.c call memcpy_fromiovecend(). This function is not available when CONFIG_NET is not enabled. socket.h already includes uio.h, so no callers need updating. Reported-by: Randy Dunlap <rdunlap@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Diffstat (limited to 'lib')
-rw-r--r--lib/iovec.c55
1 files changed, 55 insertions, 0 deletions
diff --git a/lib/iovec.c b/lib/iovec.c
index 454baa88bf27..7a7c2da4cddf 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);