There is lots of good documentation in highmem.h that isn't being pulled
into the html documentation. Fix up a couple of minor glitches and
include it.
Signed-off-by: Matthew Wilcox (Oracle) <[email protected]>
---
Documentation/core-api/mm-api.rst | 1 +
include/linux/highmem.h | 17 +++++++++--------
2 files changed, 10 insertions(+), 8 deletions(-)
diff --git a/Documentation/core-api/mm-api.rst b/Documentation/core-api/mm-api.rst
index 395835f9289f..2027aee5f2d9 100644
--- a/Documentation/core-api/mm-api.rst
+++ b/Documentation/core-api/mm-api.rst
@@ -54,6 +54,7 @@ Virtually Contiguous Mappings
.. kernel-doc:: mm/vmalloc.c
:export:
+.. kernel-doc:: include/linux/highmem.h
File Mapping and Page Cache
===========================
diff --git a/include/linux/highmem.h b/include/linux/highmem.h
index 861ad00fb32a..fc43e81cf4db 100644
--- a/include/linux/highmem.h
+++ b/include/linux/highmem.h
@@ -37,8 +37,8 @@
static inline void *kmap(struct page *page);
/**
- * kunmap - Unmap the virtual address mapped by kmap()
- * @addr: Virtual address to be unmapped
+ * kunmap - Unmap the page mapped by kmap()
+ * @page: Page to be unmapped
*
* Counterpart to kmap(). A NOOP for CONFIG_HIGHMEM=n and for mappings of
* pages in the low memory area.
@@ -69,13 +69,13 @@ static inline void kmap_flush_unused(void);
*
* Requires careful handling when nesting multiple mappings because the map
* management is stack based. The unmap has to be in the reverse order of
- * the map operation:
+ * the map operation::
*
- * addr1 = kmap_local_page(page1);
- * addr2 = kmap_local_page(page2);
- * ...
- * kunmap_local(addr2);
- * kunmap_local(addr1);
+ * addr1 = kmap_local_page(page1);
+ * addr2 = kmap_local_page(page2);
+ * ...
+ * kunmap_local(addr2);
+ * kunmap_local(addr1);
*
* Unmapping addr1 before addr2 is invalid and causes malfunction.
*
@@ -156,6 +156,7 @@ static inline void *kmap_atomic(struct page *page);
* the side effects of kmap_atomic(), i.e. reenabling pagefaults and
* preemption.
*/
+static inline void kunmap_atomic(void *addr);
/* Highmem related interfaces for management code */
static inline unsigned int nr_free_highpages(void);
--
2.30.2
On Thu, 22 Jul 2021 03:18:42 +0100 "Matthew Wilcox (Oracle)" <[email protected]> wrote:
> There is lots of good documentation in highmem.h that isn't being pulled
> into the html documentation. Fix up a couple of minor glitches and
> include it.
>
> --- a/include/linux/highmem.h
> +++ b/include/linux/highmem.h
>
> ...
>
> @@ -156,6 +156,7 @@ static inline void *kmap_atomic(struct page *page);
> * the side effects of kmap_atomic(), i.e. reenabling pagefaults and
> * preemption.
> */
> +static inline void kunmap_atomic(void *addr);
>
> /* Highmem related interfaces for management code */
> static inline unsigned int nr_free_highpages(void);
This hunk broke the i386 allmodconfig build.
In file included from ./include/linux/highmem.h:14,
from ./include/linux/bio.h:8,
from ./include/linux/blkdev.h:18,
from ./include/linux/blk-cgroup.h:23,
from ./include/linux/writeback.h:14,
from ./include/linux/memcontrol.h:22,
from ./include/linux/swap.h:9,
from ./include/linux/suspend.h:5,
from arch/x86/kernel/asm-offsets.c:13:
./include/linux/highmem-internal.h:216:1: error: expected identifier or '(' before 'do'
216 | do { \
| ^~
./include/linux/highmem.h:122:20: note: in expansion of macro 'kunmap_atomic'
122 | static inline void kunmap_atomic(void *addr);
| ^~~~~~~~~~~~~
./include/linux/highmem-internal.h:219:3: error: expected identifier or '(' before 'while'
219 | } while (0)
| ^~~~~
./include/linux/highmem.h:122:20: note: in expansion of macro 'kunmap_atomic'
122 | static inline void kunmap_atomic(void *addr);
| ^~~~~~~~~~~~~
make[1]: *** [scripts/Makefile.build:117: arch/x86/kernel/asm-offsets.s] Error 1
make: *** [Makefile:1213: prepare0] Error 2
I think I can see what you were trying to do there. How about we
instead move the kunmap_atomic() kerneldoc to an appropriate place?