lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

[PATCH] CRIS update: mm

Browse Source 
Memory management patches.

* SMP support.
* Non-executable stack (on v32).
* 4-level page tables.
* Added simple Thread Local Storage support.

Signed-off-by: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Mikael Starvik
2005-07-27 11:44:39 -07:00
committed by Linus Torvalds
parent 7cf32cad15
commit 4f18cfbf09
4 changed files with 135 additions and 48 deletions
Download Patch File Download Diff File Expand all files Collapse all files

95
arch/cris/mm/fault.c
View File

@@ -6,6 +6,38 @@
* Authors: Bjorn Wesen
*
* $Log: fault.c,v $
* Revision 1.20 2005/03/04 08:16:18 starvik
* Merge of Linux 2.6.11.
*
* Revision 1.19 2005/01/14 10:07:59 starvik
* Fixed warning.
*
* Revision 1.18 2005/01/12 08:10:14 starvik
* Readded the change of frametype when handling kernel page fault fixup
* for v10. This is necessary to avoid that the CPU remakes the faulting
* access.
*
* Revision 1.17 2005/01/11 13:53:05 starvik
* Use raw_printk.
*
* Revision 1.16 2004/12/17 11:39:41 starvik
* SMP support.
*
* Revision 1.15 2004/11/23 18:36:18 starvik
* Stack is now non-executable.
* Signal handler trampolines are placed in a reserved page mapped into all
* processes.
*
* Revision 1.14 2004/11/23 07:10:21 starvik
* Moved find_fixup_code to generic code.
*
* Revision 1.13 2004/11/23 07:00:54 starvik
* Actually use the execute permission bit in the MMU. This makes it possible
* to prevent e.g. attacks where executable code is put on the stack.
*
* Revision 1.12 2004/09/29 06:16:04 starvik
* Use instruction_pointer
*
* Revision 1.11 2004/05/14 07:58:05 starvik
* Merge of changes from 2.4
*
@@ -103,6 +135,7 @@
extern int find_fixup_code(struct pt_regs *);
extern void die_if_kernel(const char *, struct pt_regs *, long);
extern int raw_printk(const char *fmt, ...);
/* debug of low-level TLB reload */
#undef DEBUG
@@ -118,7 +151,8 @@ extern void die_if_kernel(const char *, struct pt_regs *, long);
/* current active page directory */
volatile pgd_t *current_pgd;
volatile DEFINE_PER_CPU(pgd_t *,current_pgd);
unsigned long cris_signal_return_page;
/*
* This routine handles page faults. It determines the address,
@@ -146,8 +180,9 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
struct vm_area_struct * vma;
siginfo_t info;
D(printk("Page fault for %X at %X, prot %d write %d\n",
address, regs->erp, protection, writeaccess));
D(printk("Page fault for %lX on %X at %lX, prot %d write %d\n",
address, smp_processor_id(), instruction_pointer(regs),
protection, writeaccess));
tsk = current;
@@ -175,8 +210,19 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
!user_mode(regs))
goto vmalloc_fault;
/* When stack execution is not allowed we store the signal
* trampolines in the reserved cris_signal_return_page.
* Handle this in the exact same way as vmalloc (we know
* that the mapping is there and is valid so no need to
* call handle_mm_fault).
*/
if (cris_signal_return_page &&
address == cris_signal_return_page &&
!protection && user_mode(regs))
goto vmalloc_fault;
/* we can and should enable interrupts at this point */
sti();
local_irq_enable();
mm = tsk->mm;
info.si_code = SEGV_MAPERR;
@@ -220,7 +266,10 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
/* first do some preliminary protection checks */
if (writeaccess) {
if (writeaccess == 2){
if (!(vma->vm_flags & VM_EXEC))
goto bad_area;
} else if (writeaccess == 1) {
if (!(vma->vm_flags & VM_WRITE))
goto bad_area;
} else {
@@ -234,7 +283,7 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
* the fault.
*/
switch (handle_mm_fault(mm, vma, address, writeaccess)) {
switch (handle_mm_fault(mm, vma, address, writeaccess & 1)) {
case 1:
tsk->min_flt++;
break;
@@ -292,10 +341,10 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
*/
if ((unsigned long) (address) < PAGE_SIZE)
printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference");
raw_printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference");
else
printk(KERN_ALERT "Unable to handle kernel access");
printk(" at virtual address %08lx\n",address);
raw_printk(KERN_ALERT "Unable to handle kernel access");
raw_printk(" at virtual address %08lx\n",address);
die_if_kernel("Oops", regs, (writeaccess << 1) | protection);
@@ -346,10 +395,11 @@ vmalloc_fault:
int offset = pgd_index(address);
pgd_t *pgd, *pgd_k;
pud_t *pud, *pud_k;
pmd_t *pmd, *pmd_k;
pte_t *pte_k;
pgd = (pgd_t *)current_pgd + offset;
pgd = (pgd_t *)per_cpu(current_pgd, smp_processor_id()) + offset;
pgd_k = init_mm.pgd + offset;
/* Since we're two-level, we don't need to do both
@@ -364,8 +414,13 @@ vmalloc_fault:
* it exists.
*/
pmd = pmd_offset(pgd, address);
pmd_k = pmd_offset(pgd_k, address);
pud = pud_offset(pgd, address);
pud_k = pud_offset(pgd_k, address);
if (!pud_present(*pud_k))
goto no_context;
pmd = pmd_offset(pud, address);
pmd_k = pmd_offset(pud_k, address);
if (!pmd_present(*pmd_k))
goto bad_area_nosemaphore;
@@ -385,3 +440,19 @@ vmalloc_fault:
return;
}
}
/* Find fixup code. */
int
find_fixup_code(struct pt_regs *regs)
{
const struct exception_table_entry *fixup;
if ((fixup = search_exception_tables(instruction_pointer(regs))) != 0) {
/* Adjust the instruction pointer in the stackframe. */
instruction_pointer(regs) = fixup->fixup;
arch_fixup(regs);
return 1;
}
return 0;
}