Commit a1f242ff authored by Benjamin Herrenschmidt's avatar Benjamin Herrenschmidt Committed by Linus Torvalds

powerpc ioremap_prot

This adds ioremap_prot and pte_pgprot() so that one can extract protection
bits from a PTE and use them to ioremap_prot() (in order to support ptrace
of VM_IO | VM_PFNMAP as per Rik's patch).

This moves a couple of flag checks around in the ioremap implementations
of arch/powerpc.  There's a side effect of allowing non-cacheable and
non-guarded mappings on ppc32 which before would always have _PAGE_GUARDED
set whenever _PAGE_NO_CACHE is.

(standard ioremap will still set _PAGE_GUARDED, but ioremap_prot will be
capable of setting such a non guarded mapping).
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: default avatarRik van Riel <riel@redhat.com>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 7ae8ed50
......@@ -111,6 +111,7 @@ config PPC
select HAVE_DYNAMIC_FTRACE
select HAVE_FTRACE
select HAVE_IDE
select HAVE_IOREMAP_PROT
select HAVE_KPROBES
select HAVE_ARCH_KGDB
select HAVE_KRETPROBES
......
......@@ -145,13 +145,20 @@ void pte_free(struct mm_struct *mm, pgtable_t ptepage)
void __iomem *
ioremap(phys_addr_t addr, unsigned long size)
{
return __ioremap(addr, size, _PAGE_NO_CACHE);
return __ioremap(addr, size, _PAGE_NO_CACHE | _PAGE_GUARDED);
}
EXPORT_SYMBOL(ioremap);
void __iomem *
ioremap_flags(phys_addr_t addr, unsigned long size, unsigned long flags)
{
/* writeable implies dirty for kernel addresses */
if (flags & _PAGE_RW)
flags |= _PAGE_DIRTY | _PAGE_HWWRITE;
/* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */
flags &= ~(_PAGE_USER | _PAGE_EXEC | _PAGE_HWEXEC);
return __ioremap(addr, size, flags);
}
EXPORT_SYMBOL(ioremap_flags);
......@@ -163,6 +170,14 @@ __ioremap(phys_addr_t addr, unsigned long size, unsigned long flags)
phys_addr_t p;
int err;
/* Make sure we have the base flags */
if ((flags & _PAGE_PRESENT) == 0)
flags |= _PAGE_KERNEL;
/* Non-cacheable page cannot be coherent */
if (flags & _PAGE_NO_CACHE)
flags &= ~_PAGE_COHERENT;
/*
* Choose an address to map it to.
* Once the vmalloc system is running, we use it.
......@@ -219,11 +234,6 @@ __ioremap(phys_addr_t addr, unsigned long size, unsigned long flags)
v = (ioremap_bot -= size);
}
if ((flags & _PAGE_PRESENT) == 0)
flags |= _PAGE_KERNEL;
if (flags & _PAGE_NO_CACHE)
flags |= _PAGE_GUARDED;
/*
* Should check if it is a candidate for a BAT mapping
*/
......
......@@ -107,9 +107,18 @@ void __iomem * __ioremap_at(phys_addr_t pa, void *ea, unsigned long size,
{
unsigned long i;
/* Make sure we have the base flags */
if ((flags & _PAGE_PRESENT) == 0)
flags |= pgprot_val(PAGE_KERNEL);
/* Non-cacheable page cannot be coherent */
if (flags & _PAGE_NO_CACHE)
flags &= ~_PAGE_COHERENT;
/* We don't support the 4K PFN hack with ioremap */
if (flags & _PAGE_4K_PFN)
return NULL;
WARN_ON(pa & ~PAGE_MASK);
WARN_ON(((unsigned long)ea) & ~PAGE_MASK);
WARN_ON(size & ~PAGE_MASK);
......@@ -190,6 +199,13 @@ void __iomem * ioremap(phys_addr_t addr, unsigned long size)
void __iomem * ioremap_flags(phys_addr_t addr, unsigned long size,
unsigned long flags)
{
/* writeable implies dirty for kernel addresses */
if (flags & _PAGE_RW)
flags |= _PAGE_DIRTY;
/* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */
flags &= ~(_PAGE_USER | _PAGE_EXEC);
if (ppc_md.ioremap)
return ppc_md.ioremap(addr, size, flags);
return __ioremap(addr, size, flags);
......
......@@ -617,7 +617,8 @@ static inline void iosync(void)
* and can be hooked by the platform via ppc_md
*
* * ioremap_flags allows to specify the page flags as an argument and can
* also be hooked by the platform via ppc_md
* also be hooked by the platform via ppc_md. ioremap_prot is the exact
* same thing as ioremap_flags.
*
* * ioremap_nocache is identical to ioremap
*
......@@ -639,6 +640,8 @@ extern void __iomem *ioremap(phys_addr_t address, unsigned long size);
extern void __iomem *ioremap_flags(phys_addr_t address, unsigned long size,
unsigned long flags);
#define ioremap_nocache(addr, size) ioremap((addr), (size))
#define ioremap_prot(addr, size, prot) ioremap_flags((addr), (size), (prot))
extern void iounmap(volatile void __iomem *addr);
extern void __iomem *__ioremap(phys_addr_t, unsigned long size,
......
......@@ -51,6 +51,9 @@
#define _PAGE_HPTEFLAGS (_PAGE_BUSY | _PAGE_HASHPTE | \
_PAGE_SECONDARY | _PAGE_GROUP_IX)
/* There is no 4K PFN hack on 4K pages */
#define _PAGE_4K_PFN 0
/* PAGE_MASK gives the right answer below, but only by accident */
/* It should be preserving the high 48 bits and then specifically */
/* preserving _PAGE_SECONDARY | _PAGE_GROUP_IX */
......
......@@ -395,6 +395,12 @@ extern int icache_44x_need_flush;
#ifndef _PAGE_EXEC
#define _PAGE_EXEC 0
#endif
#ifndef _PAGE_ENDIAN
#define _PAGE_ENDIAN 0
#endif
#ifndef _PAGE_COHERENT
#define _PAGE_COHERENT 0
#endif
#ifndef _PMD_PRESENT_MASK
#define _PMD_PRESENT_MASK _PMD_PRESENT
#endif
......@@ -405,6 +411,12 @@ extern int icache_44x_need_flush;
#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
#define PAGE_PROT_BITS __pgprot(_PAGE_GUARDED | _PAGE_COHERENT | _PAGE_NO_CACHE | \
_PAGE_WRITETHRU | _PAGE_ENDIAN | \
_PAGE_USER | _PAGE_ACCESSED | \
_PAGE_RW | _PAGE_HWWRITE | _PAGE_DIRTY | \
_PAGE_EXEC | _PAGE_HWEXEC)
/*
* Note: the _PAGE_COHERENT bit automatically gets set in the hardware
* PTE if CONFIG_SMP is defined (hash_page does this); there is no need
......@@ -538,6 +550,10 @@ static inline pte_t pte_mkyoung(pte_t pte) {
pte_val(pte) |= _PAGE_ACCESSED; return pte; }
static inline pte_t pte_mkspecial(pte_t pte) {
return pte; }
static inline unsigned long pte_pgprot(pte_t pte)
{
return __pgprot(pte_val(pte)) & PAGE_PROT_BITS;
}
static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
{
......
......@@ -117,6 +117,10 @@
#define PAGE_AGP __pgprot(_PAGE_BASE | _PAGE_WRENABLE | _PAGE_NO_CACHE)
#define HAVE_PAGE_AGP
#define PAGE_PROT_BITS __pgprot(_PAGE_GUARDED | _PAGE_COHERENT | \
_PAGE_NO_CACHE | _PAGE_WRITETHRU | \
_PAGE_4K_PFN | _PAGE_RW | _PAGE_USER | \
_PAGE_ACCESSED | _PAGE_DIRTY | _PAGE_EXEC)
/* PTEIDX nibble */
#define _PTEIDX_SECONDARY 0x8
#define _PTEIDX_GROUP_IX 0x7
......@@ -262,6 +266,10 @@ static inline pte_t pte_mkhuge(pte_t pte) {
return pte; }
static inline pte_t pte_mkspecial(pte_t pte) {
return pte; }
static inline unsigned long pte_pgprot(pte_t pte)
{
return __pgprot(pte_val(pte)) & PAGE_PROT_BITS;
}
/* Atomic PTE updates */
static inline unsigned long pte_update(struct mm_struct *mm,
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment