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[PATCH] EFI, /dev/mem: simplify efi_mem_attribute_range()

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Pass the size, not a pointer to the size, to efi_mem_attribute_range().

This function validates memory regions for the /dev/mem read/write/mmap paths.
The pointer allows arches to reduce the size of the range, but I think that's
unnecessary complexity.  Simplifying it will let me use
efi_mem_attribute_range() to improve the ia64 ioremap() implementation.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Matt Domsch <Matt_Domsch@dell.com>
Cc: "Tolentino, Matthew E" <matthew.e.tolentino@intel.com>
Cc: "Brown, Len" <len.brown@intel.com>
Cc: Andi Kleen <ak@muc.de>
Acked-by: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Bjorn Helgaas 2006-03-26 01:37:05 -08:00 committed by Linus Torvalds
parent 3ed3bce846
commit 136939a2b5
4 changed files with 30 additions and 35 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

41
arch/ia64/kernel/efi.c
View File

@ -677,27 +677,34 @@ EXPORT_SYMBOL(efi_mem_attributes);
/*
* Determines whether the memory at phys_addr supports the desired
* attribute (WB, UC, etc). If this returns 1, the caller can safely
* access *size bytes at phys_addr with the specified attribute.
* access size bytes at phys_addr with the specified attribute.
*/
static int
efi_mem_attribute_range (unsigned long phys_addr, unsigned long *size, u64 attr)
int
efi_mem_attribute_range (unsigned long phys_addr, unsigned long size, u64 attr)
{
unsigned long end = phys_addr + size;
efi_memory_desc_t *md = efi_memory_descriptor(phys_addr);
unsigned long md_end;
if (!md || (md->attribute & attr) != attr)
/*
* Some firmware doesn't report MMIO regions in the EFI memory
* map. The Intel BigSur (a.k.a. HP i2000) has this problem.
* On those platforms, we have to assume UC is valid everywhere.
*/
if (!md || (md->attribute & attr) != attr) {
if (attr == EFI_MEMORY_UC && !efi_memmap_has_mmio())
return 1;
return 0;
}
do {
md_end = efi_md_end(md);
if (phys_addr + *size <= md_end)
unsigned long md_end = efi_md_end(md);
if (end <= md_end)
return 1;
md = efi_memory_descriptor(md_end);
if (!md || (md->attribute & attr) != attr) {
*size = md_end - phys_addr;
return 1;
}
if (!md || (md->attribute & attr) != attr)
return 0;
} while (md);
return 0;
}
@ -708,7 +715,7 @@ efi_mem_attribute_range (unsigned long phys_addr, unsigned long *size, u64 attr)
* control access size.
*/
int
valid_phys_addr_range (unsigned long phys_addr, unsigned long *size)
valid_phys_addr_range (unsigned long phys_addr, unsigned long size)
{
return efi_mem_attribute_range(phys_addr, size, EFI_MEMORY_WB);
}
@ -723,7 +730,7 @@ valid_phys_addr_range (unsigned long phys_addr, unsigned long *size)
* because that doesn't appear in the boot-time EFI memory map.
*/
int
valid_mmap_phys_addr_range (unsigned long phys_addr, unsigned long *size)
valid_mmap_phys_addr_range (unsigned long phys_addr, unsigned long size)
{
if (efi_mem_attribute_range(phys_addr, size, EFI_MEMORY_WB))
return 1;
@ -731,14 +738,6 @@ valid_mmap_phys_addr_range (unsigned long phys_addr, unsigned long *size)
if (efi_mem_attribute_range(phys_addr, size, EFI_MEMORY_UC))
return 1;
/*
* Some firmware doesn't report MMIO regions in the EFI memory map.
* The Intel BigSur (a.k.a. HP i2000) has this problem. In this
* case, we can't use the EFI memory map to validate mmap requests.
*/
if (!efi_memmap_has_mmio())
return 1;
return 0;
}

18
drivers/char/mem.c
View File

@ -88,21 +88,15 @@ static inline int uncached_access(struct file *file, unsigned long addr)
}
#ifndef ARCH_HAS_VALID_PHYS_ADDR_RANGE
static inline int valid_phys_addr_range(unsigned long addr, size_t *count)
static inline int valid_phys_addr_range(unsigned long addr, size_t count)
{
unsigned long end_mem;
end_mem = __pa(high_memory);
if (addr >= end_mem)
if (addr + count > __pa(high_memory))
return 0;
if (*count > end_mem - addr)
*count = end_mem - addr;
return 1;
}
static inline int valid_mmap_phys_addr_range(unsigned long addr, size_t *size)
static inline int valid_mmap_phys_addr_range(unsigned long addr, size_t size)
{
return 1;
}
@ -119,7 +113,7 @@ static ssize_t read_mem(struct file * file, char __user * buf,
ssize_t read, sz;
char *ptr;
if (!valid_phys_addr_range(p, &count))
if (!valid_phys_addr_range(p, count))
return -EFAULT;
read = 0;
#ifdef __ARCH_HAS_NO_PAGE_ZERO_MAPPED
@ -177,7 +171,7 @@ static ssize_t write_mem(struct file * file, const char __user * buf,
unsigned long copied;
void *ptr;
if (!valid_phys_addr_range(p, &count))
if (!valid_phys_addr_range(p, count))
return -EFAULT;
written = 0;
@ -249,7 +243,7 @@ static int mmap_mem(struct file * file, struct vm_area_struct * vma)
{
size_t size = vma->vm_end - vma->vm_start;
if (!valid_mmap_phys_addr_range(vma->vm_pgoff << PAGE_SHIFT, &size))
if (!valid_mmap_phys_addr_range(vma->vm_pgoff << PAGE_SHIFT, size))
return -EINVAL;
vma->vm_page_prot = phys_mem_access_prot(file, vma->vm_pgoff,

4
include/asm-ia64/io.h
View File

@ -88,8 +88,8 @@ phys_to_virt (unsigned long address)
}
#define ARCH_HAS_VALID_PHYS_ADDR_RANGE
extern int valid_phys_addr_range (unsigned long addr, size_t *count); /* efi.c */
extern int valid_mmap_phys_addr_range (unsigned long addr, size_t *count);
extern int valid_phys_addr_range (unsigned long addr, size_t count); /* efi.c */
extern int valid_mmap_phys_addr_range (unsigned long addr, size_t count);
/*
* The following two macros are deprecated and scheduled for removal.

2
include/linux/efi.h
View File

@ -292,6 +292,8 @@ extern void efi_enter_virtual_mode (void); /* switch EFI to virtual mode, if pos
extern u64 efi_get_iobase (void);
extern u32 efi_mem_type (unsigned long phys_addr);
extern u64 efi_mem_attributes (unsigned long phys_addr);
extern int efi_mem_attribute_range (unsigned long phys_addr, unsigned long size,
u64 attr);
extern int __init efi_uart_console_only (void);
extern void efi_initialize_iomem_resources(struct resource *code_resource,
struct resource *data_resource);