We can't support vmap on NOMMU systems, so add a new vcoalesce function
which combines maps via kmalloc. A bit more overhead, but at least it
works. For MMU systems, vcoalesce simply redirects to vmap.
Signed-off-by: Mike Frysinger <[email protected]>
---
v2
- fix MMU version of vcoalesce
include/linux/vmalloc.h | 3 +++
mm/nommu.c | 22 +++++++++++++++++++++-
2 files changed, 24 insertions(+), 1 deletions(-)
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 4ed6fcd..6b3480c 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -44,10 +44,13 @@ extern void vm_unmap_aliases(void);
#ifdef CONFIG_MMU
extern void __init vmalloc_init(void);
+#define vcoalesce(...) vmap(__VA_ARGS__)
#else
static inline void vmalloc_init(void)
{
}
+extern void *vcoalesce(struct page **pages, unsigned int count,
+ unsigned long flags, pgprot_t prot);
#endif
extern void *vmalloc(unsigned long size);
diff --git a/mm/nommu.c b/mm/nommu.c
index cb86e7d..7812938 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -404,6 +404,26 @@ void *vmalloc_32_user(unsigned long size)
}
EXPORT_SYMBOL(vmalloc_32_user);
+void *vcoalesce(struct page **pages, unsigned int count,
+ unsigned long flags, pgprot_t prot)
+{
+ unsigned int i;
+ void *new_map, *page_data;
+
+ new_map = kmalloc(count << PAGE_SHIFT, GFP_KERNEL);
+ if (!new_map)
+ return NULL;
+
+ for (i = 0; i < count; ++i) {
+ page_data = kmap(pages[i]);
+ memcpy(new_map + (i << PAGE_SHIFT), page_data, PAGE_SIZE);
+ kunmap(page_data);
+ }
+
+ return new_map;
+}
+EXPORT_SYMBOL(vcoalesce);
+
void *vmap(struct page **pages, unsigned int count, unsigned long flags, pgprot_t prot)
{
BUG();
@@ -413,7 +433,7 @@ EXPORT_SYMBOL(vmap);
void vunmap(const void *addr)
{
- BUG();
+ kfree(addr);
}
EXPORT_SYMBOL(vunmap);
--
1.7.4.1