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Diffstat (limited to 'arch/um/kernel/trap_kern.c')
-rw-r--r--arch/um/kernel/trap_kern.c55
1 files changed, 13 insertions, 42 deletions
diff --git a/arch/um/kernel/trap_kern.c b/arch/um/kernel/trap_kern.c
index c20aef12059..b5fc89fe9ea 100644
--- a/arch/um/kernel/trap_kern.c
+++ b/arch/um/kernel/trap_kern.c
@@ -26,6 +26,7 @@
#include "mem.h"
#include "mem_kern.h"
+/* Note this is constrained to return 0, -EFAULT, -EACCESS, -ENOMEM by segv(). */
int handle_page_fault(unsigned long address, unsigned long ip,
int is_write, int is_user, int *code_out)
{
@@ -35,7 +36,6 @@ int handle_page_fault(unsigned long address, unsigned long ip,
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
- unsigned long page;
int err = -EFAULT;
*code_out = SEGV_MAPERR;
@@ -52,7 +52,7 @@ int handle_page_fault(unsigned long address, unsigned long ip,
else if(expand_stack(vma, address))
goto out;
- good_area:
+good_area:
*code_out = SEGV_ACCERR;
if(is_write && !(vma->vm_flags & VM_WRITE))
goto out;
@@ -60,9 +60,8 @@ int handle_page_fault(unsigned long address, unsigned long ip,
if(!(vma->vm_flags & (VM_READ | VM_EXEC)))
goto out;
- page = address & PAGE_MASK;
do {
- survive:
+survive:
switch (handle_mm_fault(mm, vma, address, is_write)){
case VM_FAULT_MINOR:
current->min_flt++;
@@ -79,16 +78,16 @@ int handle_page_fault(unsigned long address, unsigned long ip,
default:
BUG();
}
- pgd = pgd_offset(mm, page);
- pud = pud_offset(pgd, page);
- pmd = pmd_offset(pud, page);
- pte = pte_offset_kernel(pmd, page);
+ pgd = pgd_offset(mm, address);
+ pud = pud_offset(pgd, address);
+ pmd = pmd_offset(pud, address);
+ pte = pte_offset_kernel(pmd, address);
} while(!pte_present(*pte));
err = 0;
*pte = pte_mkyoung(*pte);
if(pte_write(*pte)) *pte = pte_mkdirty(*pte);
- flush_tlb_page(vma, page);
- out:
+ flush_tlb_page(vma, address);
+out:
up_read(&mm->mmap_sem);
return(err);
@@ -144,19 +143,18 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, void *sc)
panic("Kernel mode fault at addr 0x%lx, ip 0x%lx",
address, ip);
- if(err == -EACCES){
+ if (err == -EACCES) {
si.si_signo = SIGBUS;
si.si_errno = 0;
si.si_code = BUS_ADRERR;
si.si_addr = (void *)address;
current->thread.arch.faultinfo = fi;
force_sig_info(SIGBUS, &si, current);
- }
- else if(err == -ENOMEM){
+ } else if (err == -ENOMEM) {
printk("VM: killing process %s\n", current->comm);
do_exit(SIGKILL);
- }
- else {
+ } else {
+ BUG_ON(err != -EFAULT);
si.si_signo = SIGSEGV;
si.si_addr = (void *) address;
current->thread.arch.faultinfo = fi;
@@ -200,30 +198,3 @@ void winch(int sig, union uml_pt_regs *regs)
void trap_init(void)
{
}
-
-DEFINE_SPINLOCK(trap_lock);
-
-static int trap_index = 0;
-
-int next_trap_index(int limit)
-{
- int ret;
-
- spin_lock(&trap_lock);
- ret = trap_index;
- if(++trap_index == limit)
- trap_index = 0;
- spin_unlock(&trap_lock);
- return(ret);
-}
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only. This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */