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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/drzeus/mmc

Browse Source 
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/drzeus/mmc:
  sdhci: highmem capable PIO routines
  sg: reimplement sg mapping iterator
  mmc_test: print message when attaching to card
  mmc: Remove Russell as primecell mci maintainer
  mmc_block: bounce buffer highmem support
  sdhci: fix bad warning from commit c8b3e02
  sdhci: add warnings for bad buffers in ADMA path
  mmc_test: test oversized sg lists
  mmc_test: highmem tests
  s3cmci: ensure host stopped on machine shutdown
  au1xmmc: suspend/resume implementation
  s3cmci: fixes for section mismatch warnings
  pxamci: trivial fix of DMA alignment register bit clearing
This commit is contained in:
Linus Torvalds
2008-07-23 12:04:34 -07:00
parent 5554b35933 7659150c60
commit 20b7997e8a
10 changed files with 567 additions and 242 deletions
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168
lib/scatterlist.c
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@@ -294,6 +294,117 @@ int sg_alloc_table(struct sg_table *table, unsigned int nents, gfp_t gfp_mask)
}
EXPORT_SYMBOL(sg_alloc_table);
/**
* sg_miter_start - start mapping iteration over a sg list
* @miter: sg mapping iter to be started
* @sgl: sg list to iterate over
* @nents: number of sg entries
*
* Description:
* Starts mapping iterator @miter.
*
* Context:
* Don't care.
*/
void sg_miter_start(struct sg_mapping_iter *miter, struct scatterlist *sgl,
unsigned int nents, unsigned int flags)
{
memset(miter, 0, sizeof(struct sg_mapping_iter));
miter->__sg = sgl;
miter->__nents = nents;
miter->__offset = 0;
miter->__flags = flags;
}
EXPORT_SYMBOL(sg_miter_start);
/**
* sg_miter_next - proceed mapping iterator to the next mapping
* @miter: sg mapping iter to proceed
*
* Description:
* Proceeds @miter@ to the next mapping. @miter@ should have been
* started using sg_miter_start(). On successful return,
* @miter@->page, @miter@->addr and @miter@->length point to the
* current mapping.
*
* Context:
* IRQ disabled if SG_MITER_ATOMIC. IRQ must stay disabled till
* @miter@ is stopped. May sleep if !SG_MITER_ATOMIC.
*
* Returns:
* true if @miter contains the next mapping. false if end of sg
* list is reached.
*/
bool sg_miter_next(struct sg_mapping_iter *miter)
{
unsigned int off, len;
/* check for end and drop resources from the last iteration */
if (!miter->__nents)
return false;
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;
}
/* map the next page */
off = miter->__sg->offset + miter->__offset;
len = miter->__sg->length - miter->__offset;
miter->page = nth_page(sg_page(miter->__sg), off >> PAGE_SHIFT);
off &= ~PAGE_MASK;
miter->length = min_t(unsigned int, len, PAGE_SIZE - off);
miter->consumed = miter->length;
if (miter->__flags & SG_MITER_ATOMIC)
miter->addr = kmap_atomic(miter->page, KM_BIO_SRC_IRQ) + off;
else
miter->addr = kmap(miter->page) + off;
return true;
}
EXPORT_SYMBOL(sg_miter_next);
/**
* sg_miter_stop - stop mapping iteration
* @miter: sg mapping iter to be stopped
*
* Description:
* Stops mapping iterator @miter. @miter should have been started
* started using sg_miter_start(). A stopped iteration can be
* resumed by calling sg_miter_next() on it. This is useful when
* resources (kmap) need to be released during iteration.
*
* Context:
* IRQ disabled if the SG_MITER_ATOMIC is set. Don't care otherwise.
*/
void sg_miter_stop(struct sg_mapping_iter *miter)
{
WARN_ON(miter->consumed > miter->length);
/* drop resources from the last iteration */
if (miter->addr) {
miter->__offset += miter->consumed;
if (miter->__flags & SG_MITER_ATOMIC) {
WARN_ON(!irqs_disabled());
kunmap_atomic(miter->addr, KM_BIO_SRC_IRQ);
} else
kunmap(miter->addr);
miter->page = NULL;
miter->addr = NULL;
miter->length = 0;
miter->consumed = 0;
}
}
EXPORT_SYMBOL(sg_miter_stop);
/**
* sg_copy_buffer - Copy data between a linear buffer and an SG list
* @sgl: The SG list
@@ -309,56 +420,29 @@ EXPORT_SYMBOL(sg_alloc_table);
static size_t sg_copy_buffer(struct scatterlist *sgl, unsigned int nents,
void *buf, size_t buflen, int to_buffer)
{
struct scatterlist *sg;
size_t buf_off = 0;
int i;
unsigned int offset = 0;
struct sg_mapping_iter miter;
WARN_ON(!irqs_disabled());
sg_miter_start(&miter, sgl, nents, SG_MITER_ATOMIC);
for_each_sg(sgl, sg, nents, i) {
struct page *page;
int n = 0;
unsigned int sg_off = sg->offset;
unsigned int sg_copy = sg->length;
while (sg_miter_next(&miter) && offset < buflen) {
unsigned int len;
if (sg_copy > buflen)
sg_copy = buflen;
buflen -= sg_copy;
len = min(miter.length, buflen - offset);
while (sg_copy > 0) {
unsigned int page_copy;
void *p;
page_copy = PAGE_SIZE - sg_off;
if (page_copy > sg_copy)
page_copy = sg_copy;
page = nth_page(sg_page(sg), n);
p = kmap_atomic(page, KM_BIO_SRC_IRQ);
if (to_buffer)
memcpy(buf + buf_off, p + sg_off, page_copy);
else {
memcpy(p + sg_off, buf + buf_off, page_copy);
flush_kernel_dcache_page(page);
}
kunmap_atomic(p, KM_BIO_SRC_IRQ);
buf_off += page_copy;
sg_off += page_copy;
if (sg_off == PAGE_SIZE) {
sg_off = 0;
n++;
}
sg_copy -= page_copy;
if (to_buffer)
memcpy(buf + offset, miter.addr, len);
else {
memcpy(miter.addr, buf + offset, len);
flush_kernel_dcache_page(miter.page);
}
if (!buflen)
break;
offset += len;
}
return buf_off;
sg_miter_stop(&miter);
return offset;
}
/**