2002-10-01 04:49:12

by David Gibson

[permalink] [raw]
Subject: [PATCH] Add gfp_mask to get_vm_area()

Linus, please consider this patch. It renames get_vm_area() to
__get_vm_area() and adds a gfp_mask parameter which is passed on to
kmalloc(). get_vm_area(size,flags) is then defined as as
__get_vm_area(size,flags,GFP_KERNEL) to avoid messing with existing

We need this in order to sanely make pci_alloc_consistent() (and other
consistent allocation functions) obey the DMA-mapping.txt rules on PPC
embedded machines (specifically the requirement that it be callable
from interrupt context).

DaveM seems to think it's ok :-)

diff -urN /home/dgibson/kernel/linuxppc-2.5/include/linux/vmalloc.h linux-bluefish/include/linux/vmalloc.h
--- /home/dgibson/kernel/linuxppc-2.5/include/linux/vmalloc.h 2002-09-20 14:36:15.000000000 +1000
+++ linux-bluefish/include/linux/vmalloc.h 2002-10-01 14:29:10.000000000 +1000
@@ -32,7 +32,8 @@
* Lowlevel-APIs (not for driver use!)
-extern struct vm_struct *get_vm_area(unsigned long size, unsigned long flags);
+extern struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags, int gfp_mask);
+#define get_vm_area(size, flags) __get_vm_area(size, flags, GFP_KERNEL)
extern struct vm_struct *remove_vm_area(void *addr);
extern int map_vm_area(struct vm_struct *area, pgprot_t prot,
struct page ***pages);
diff -urN /home/dgibson/kernel/linuxppc-2.5/mm/vmalloc.c linux-bluefish/mm/vmalloc.c
--- /home/dgibson/kernel/linuxppc-2.5/mm/vmalloc.c 2002-09-20 14:36:26.000000000 +1000
+++ linux-bluefish/mm/vmalloc.c 2002-10-01 14:30:02.000000000 +1000
@@ -181,21 +181,22 @@

- * get_vm_area - reserve a contingous kernel virtual area
+ * __get_vm_area - reserve a contingous kernel virtual area
* @size: size of the area
* @flags: %VM_IOREMAP for I/O mappings or VM_ALLOC
+ * @gfp_mask: gfp flags to pass to kmalloc()
* Search an area of @size in the kernel virtual mapping area,
* and reserved it for out purposes. Returns the area descriptor
* on success or %NULL on failure.
-struct vm_struct *get_vm_area(unsigned long size, unsigned long flags)
+struct vm_struct *__get_vm_area(unsigned long size, unsigned long flags, int gfp_mask)
struct vm_struct **p, *tmp, *area;
unsigned long addr = VMALLOC_START;

- area = kmalloc(sizeof(*area), GFP_KERNEL);
+ area = kmalloc(sizeof(*area), gfp_mask);
if (unlikely(!area))
return NULL;

David Gibson | For every complex problem there is a
[email protected] | solution which is simple, neat and
| wrong.