[PATCH] kevent_user: use struct kevent_mring for the page ring

Christoph Hellwig
2006-08-22T11:55:29Z

Currently struct kevent_user.print is an array of unsigned long, but it's used
as an array of pointers to struct kevent_mring everyewhere in the code.

Switch it to use the real type and cast the return value from __get_free_page /
argument to free_page.

include/linux/kevent.h | 2 +-
kernel/kevent/kevent_user.c | 31 +++++++++++--------------------
2 files changed, 12 insertions(+), 21 deletions(-)

Signed-off-by: Christoph Hellwig <hch@lst.de>

Index: linux-2.6/include/linux/kevent.h
===================================================================
--- linux-2.6.orig/include/linux/kevent.h 2006-08-22 12:10:24.000000000 +0200
+++ linux-2.6/include/linux/kevent.h 2006-08-22 13:30:48.000000000 +0200
@@ -105,7 +105,7 @@

unsigned int pages_in_use;
/* Array of pages forming mapped ring buffer */
- unsigned long *pring;
+ struct kevent_mring **pring;

#ifdef CONFIG_KEVENT_USER_STAT
unsigned long im_num;
Index: linux-2.6/kernel/kevent/kevent_user.c
===================================================================
--- linux-2.6.orig/kernel/kevent/kevent_user.c 2006-08-22 13:28:06.000000000 +0200
+++ linux-2.6/kernel/kevent/kevent_user.c 2006-08-22 13:43:46.000000000 +0200
@@ -69,30 +69,21 @@

static inline void kevent_user_ring_set(struct kevent_user *u, unsigned int num)
{
- struct kevent_mring *ring;
-
- ring = (struct kevent_mring *)u->pring[0];
- ring->index = num;
+ u->pring[0]->index = num;
}

static inline void kevent_user_ring_inc(struct kevent_user *u)
{
- struct kevent_mring *ring;
-
- ring = (struct kevent_mring *)u->pring[0];
- ring->index++;
+ u->pring[0]->index++;
}

static int kevent_user_ring_grow(struct kevent_user *u)
{
- struct kevent_mring *ring;
unsigned int idx;

- ring = (struct kevent_mring *)u->pring[0];
-
- idx = (ring->index + 1) / KEVENTS_ON_PAGE;
+ idx = (u->pring[0]->index + 1) / KEVENTS_ON_PAGE;
if (idx >= u->pages_in_use) {
- u->pring[idx] = __get_free_page(GFP_KERNEL);
+ u->pring[idx] = (void *)__get_free_page(GFP_KERNEL);
if (!u->pring[idx])
return -ENOMEM;
u->pages_in_use++;
@@ -108,12 +99,12 @@
unsigned int pidx, off;
struct kevent_mring *ring, *copy_ring;

- ring = (struct kevent_mring *)k->user->pring[0];
-
+ ring = k->user->pring[0];
+
pidx = ring->index/KEVENTS_ON_PAGE;
off = ring->index%KEVENTS_ON_PAGE;

- copy_ring = (struct kevent_mring *)k->user->pring[pidx];
+ copy_ring = k->user->pring[pidx];

copy_ring->event[off].id.raw[0] = k->event.id.raw[0];
copy_ring->event[off].id.raw[1] = k->event.id.raw[1];
@@ -134,11 +125,11 @@

pnum = ALIGN(KEVENT_MAX_EVENTS*sizeof(struct mukevent) + sizeof(unsigned int), PAGE_SIZE)/PAGE_SIZE;

- u->pring = kmalloc(pnum * sizeof(unsigned long), GFP_KERNEL);
+ u->pring = kmalloc(pnum * sizeof(struct kevent_mring *), GFP_KERNEL);
if (!u->pring)
return -ENOMEM;

- u->pring[0] = __get_free_page(GFP_KERNEL);
+ u->pring[0] = (struct kevent_mring *)__get_free_page(GFP_KERNEL);
if (!u->pring[0])
goto err_out_free;

@@ -158,7 +149,7 @@
int i;

for (i = 0; i < u->pages_in_use; ++i)
- free_page(u->pring[i]);
+ free_page((unsigned long)u->pring[i]);

kfree(u->pring);
}
@@ -254,7 +245,7 @@
vma->vm_flags |= VM_RESERVED;
vma->vm_file = file;

- if (vm_insert_page(vma, start, virt_to_page((void *)u->pring[0])))
+ if (vm_insert_page(vma, start, virt_to_page(u->pring[0])))
return -EFAULT;

return 0;