X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=blobdiff_plain;f=lib%2Fscatterlist.c;h=0d475d8167bfd7f4f9909424ea29a72653b581fe;hp=b7b449dafbe5abb59fe06982e337cb31c6a7eaeb;hb=bc6c53d5a1383d5d9632adf33bd03458cfc0869d;hpb=f652c521e0bec2e70cf123f47e80117a7e6ed139

diff --git a/lib/scatterlist.c b/lib/scatterlist.c
index b7b449d..0d475d8 100644
--- a/lib/scatterlist.c
+++ b/lib/scatterlist.c
@@ -314,6 +314,7 @@ void sg_miter_start(struct sg_mapping_iter *miter, struct scatterlist *sgl,
 	miter->__sg = sgl;
 	miter->__nents = nents;
 	miter->__offset = 0;
+	WARN_ON(!(flags & (SG_MITER_TO_SG | SG_MITER_FROM_SG)));
 	miter->__flags = flags;
 }
 EXPORT_SYMBOL(sg_miter_start);
@@ -347,9 +348,12 @@ bool sg_miter_next(struct sg_mapping_iter *miter)
 	sg_miter_stop(miter);
 
 	/* get to the next sg if necessary.  __offset is adjusted by stop */
-	if (miter->__offset == miter->__sg->length && --miter->__nents) {
-		miter->__sg = sg_next(miter->__sg);
-		miter->__offset = 0;
+	while (miter->__offset == miter->__sg->length) {
+		if (--miter->__nents) {
+			miter->__sg = sg_next(miter->__sg);
+			miter->__offset = 0;
+		} else
+			return false;
 	}
 
 	/* map the next page */
@@ -391,6 +395,9 @@ void sg_miter_stop(struct sg_mapping_iter *miter)
 	if (miter->addr) {
 		miter->__offset += miter->consumed;
 
+		if (miter->__flags & SG_MITER_TO_SG)
+			flush_kernel_dcache_page(miter->page);
+
 		if (miter->__flags & SG_MITER_ATOMIC) {
 			WARN_ON(!irqs_disabled());
 			kunmap_atomic(miter->addr, KM_BIO_SRC_IRQ);
@@ -423,8 +430,14 @@ static size_t sg_copy_buffer(struct scatterlist *sgl, unsigned int nents,
 	unsigned int offset = 0;
 	struct sg_mapping_iter miter;
 	unsigned long flags;
+	unsigned int sg_flags = SG_MITER_ATOMIC;
+
+	if (to_buffer)
+		sg_flags |= SG_MITER_FROM_SG;
+	else
+		sg_flags |= SG_MITER_TO_SG;
 
-	sg_miter_start(&miter, sgl, nents, SG_MITER_ATOMIC);
+	sg_miter_start(&miter, sgl, nents, sg_flags);
 
 	local_irq_save(flags);
 
@@ -435,10 +448,8 @@ static size_t sg_copy_buffer(struct scatterlist *sgl, unsigned int nents,
 
 		if (to_buffer)
 			memcpy(buf + offset, miter.addr, len);
-		else {
+		else
 			memcpy(miter.addr, buf + offset, len);
-			flush_kernel_dcache_page(miter.page);
-		}
 
 		offset += len;
 	}