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authorMauro Carvalho Chehab <mchehab@redhat.com>2012-10-17 09:32:49 -0300
committerMauro Carvalho Chehab <mchehab@redhat.com>2012-10-17 09:32:49 -0300
commit214e2ca2b82d335935a861c253fe94c61ad77aad (patch)
treeeee42ff74d10470789d919b8499737ad0e919360 /lib/scatterlist.c
parent1fdead8ad31d3aa833bc37739273fcde89ace93c (diff)
parentddffeb8c4d0331609ef2581d84de4d763607bd37 (diff)
Merge tag 'v3.7-rc1' into staging/for_v3.8
Linux 3.7-rc1 * tag 'v3.7-rc1': (9579 commits) Linux 3.7-rc1 x86, boot: Explicitly include autoconf.h for hostprogs perf: Fix UAPI fallout ARM: config: make sure that platforms are ordered by option string ARM: config: sort select statements alphanumerically UAPI: (Scripted) Disintegrate include/linux/byteorder UAPI: (Scripted) Disintegrate include/linux UAPI: Unexport linux/blk_types.h UAPI: Unexport part of linux/ppp-comp.h perf: Handle new rbtree implementation procfs: don't need a PATH_MAX allocation to hold a string representation of an int vfs: embed struct filename inside of names_cache allocation if possible audit: make audit_inode take struct filename vfs: make path_openat take a struct filename pointer vfs: turn do_path_lookup into wrapper around struct filename variant audit: allow audit code to satisfy getname requests from its names_list vfs: define struct filename and have getname() return it btrfs: Fix compilation with user namespace support enabled userns: Fix posix_acl_file_xattr_userns gid conversion userns: Properly print bluetooth socket uids ...
Diffstat (limited to 'lib/scatterlist.c')
-rw-r--r--lib/scatterlist.c35
1 files changed, 27 insertions, 8 deletions
diff --git a/lib/scatterlist.c b/lib/scatterlist.c
index fadae774a20..3675452b23c 100644
--- a/lib/scatterlist.c
+++ b/lib/scatterlist.c
@@ -39,6 +39,25 @@ struct scatterlist *sg_next(struct scatterlist *sg)
EXPORT_SYMBOL(sg_next);
/**
+ * sg_nents - return total count of entries in scatterlist
+ * @sg: The scatterlist
+ *
+ * Description:
+ * Allows to know how many entries are in sg, taking into acount
+ * chaining as well
+ *
+ **/
+int sg_nents(struct scatterlist *sg)
+{
+ int nents;
+ for (nents = 0; sg; sg = sg_next(sg))
+ nents++;
+ return nents;
+}
+EXPORT_SYMBOL(sg_nents);
+
+
+/**
* sg_last - return the last scatterlist entry in a list
* @sgl: First entry in the scatterlist
* @nents: Number of entries in the scatterlist
@@ -404,14 +423,13 @@ EXPORT_SYMBOL(sg_miter_start);
* @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.
+ * 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.
+ * Preemption disabled if SG_MITER_ATOMIC. Preemption 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
@@ -465,7 +483,8 @@ EXPORT_SYMBOL(sg_miter_next);
* resources (kmap) need to be released during iteration.
*
* Context:
- * IRQ disabled if the SG_MITER_ATOMIC is set. Don't care otherwise.
+ * Preemption disabled if the SG_MITER_ATOMIC is set. Don't care
+ * otherwise.
*/
void sg_miter_stop(struct sg_mapping_iter *miter)
{
@@ -479,7 +498,7 @@ void sg_miter_stop(struct sg_mapping_iter *miter)
flush_kernel_dcache_page(miter->page);
if (miter->__flags & SG_MITER_ATOMIC) {
- WARN_ON(!irqs_disabled());
+ WARN_ON_ONCE(preemptible());
kunmap_atomic(miter->addr);
} else
kunmap(miter->page);