Commit 68e5e9d7 authored by Ilya Yanok's avatar Ilya Yanok Committed by Linus Torvalds
Browse files

vfb: make virtual framebuffer mmapable 



Changed things:

1. vmalloc()/vfree() replaced with rvmalloc()/rvfree() (taken from
   drivers/media/video/se401.c)

2. mmap method implemented (mostly taken from drivers/media/video/se401.c)

3. smem_start and smem_len fields of struct fb_fix_screeninfo initialized.
    (smem_start initialized with virtual address, don't know if it is really
   bad...)

[adaplas: sparse warning fix]
Signed-off-by: default avatarAntonino Daplas <adaplas@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 1ddc28d7

drivers/video/vfb.c

+74 −4
Original line number Diff line number Diff line
@@ -37,6 +37,48 @@ static void *videomemory; 
static u_long videomemorysize = VIDEOMEMSIZE;

module_param(videomemorysize, ulong, 0);



/**********************************************************************

 *

 * Memory management

 *

 **********************************************************************/

static void *rvmalloc(unsigned long size)

{

	void *mem;

	unsigned long adr;



	size = PAGE_ALIGN(size);

	mem = vmalloc_32(size);

	if (!mem)

		return NULL;



	memset(mem, 0, size); /* Clear the ram out, no junk to the user */

	adr = (unsigned long) mem;

	while (size > 0) {

		SetPageReserved(vmalloc_to_page((void *)adr));

		adr += PAGE_SIZE;

		size -= PAGE_SIZE;

	}



	return mem;

}



static void rvfree(void *mem, unsigned long size)

{

	unsigned long adr;



	if (!mem)

		return;



	adr = (unsigned long) mem;

	while ((long) size > 0) {

		ClearPageReserved(vmalloc_to_page((void *)adr));

		adr += PAGE_SIZE;

		size -= PAGE_SIZE;

	}

	vfree(mem);

}



static struct fb_var_screeninfo vfb_default __initdata = {

	.xres =		640,

	.yres =		480,
@@ -371,9 +413,35 @@ static int vfb_pan_display(struct fb_var_screeninfo *var, 
static int vfb_mmap(struct fb_info *info,

		    struct vm_area_struct *vma)

{

	unsigned long start = vma->vm_start;

	unsigned long size = vma->vm_end - vma->vm_start;

	unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;

	unsigned long page, pos;



	if (offset + size > info->fix.smem_len) {

		return -EINVAL;

	}



	pos = (unsigned long)info->fix.smem_start + offset;



	while (size > 0) {

		page = vmalloc_to_pfn((void *)pos);

		if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED)) {

			return -EAGAIN;

		}

		start += PAGE_SIZE;

		pos += PAGE_SIZE;

		if (size > PAGE_SIZE)

			size -= PAGE_SIZE;

		else

			size = 0;

	}



	vma->vm_flags |= VM_RESERVED;	/* avoid to swap out this VMA */

	return 0;



}



#ifndef MODULE

static int __init vfb_setup(char *options)

{
@@ -406,7 +474,7 @@ static int __init vfb_probe(struct platform_device *dev) 
	/*

	 * For real video cards we use ioremap.

	 */

	if (!(videomemory = vmalloc(videomemorysize)))

	if (!(videomemory = rvmalloc(videomemorysize)))

		return retval;



	/*
@@ -429,6 +497,8 @@ static int __init vfb_probe(struct platform_device *dev) 


	if (!retval || (retval == 4))

		info->var = vfb_default;

	vfb_fix.smem_start = (unsigned long) videomemory;

	vfb_fix.smem_len = videomemorysize;

	info->fix = vfb_fix;

	info->pseudo_palette = info->par;

	info->par = NULL;
@@ -452,7 +522,7 @@ err2: 
err1:

	framebuffer_release(info);

err:

	vfree(videomemory);

	rvfree(videomemory, videomemorysize);

	return retval;

}
@@ -462,7 +532,7 @@ static int vfb_remove(struct platform_device *dev) 


	if (info) {

		unregister_framebuffer(info);

		vfree(videomemory);

		rvfree(videomemory, videomemorysize);

		framebuffer_release(info);

	}

	return 0;

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