*/
if (is_cow_mapping(vm_flags)) {
ptep_set_wrprotect(src_mm, addr, src_pte);
- pte = *src_pte;
+ pte = pte_wrprotect(pte);
}
/*
src_pte = pte_offset_map_nested(src_pmd, addr);
src_ptl = pte_lockptr(src_mm, src_pmd);
spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING);
+ arch_enter_lazy_mmu_mode();
do {
/*
progress += 8;
} while (dst_pte++, src_pte++, addr += PAGE_SIZE, addr != end);
+ arch_leave_lazy_mmu_mode();
spin_unlock(src_ptl);
pte_unmap_nested(src_pte - 1);
add_mm_rss(dst_mm, rss[0], rss[1]);
int anon_rss = 0;
pte = pte_offset_map_lock(mm, pmd, addr, &ptl);
+ arch_enter_lazy_mmu_mode();
do {
pte_t ptent = *pte;
if (pte_none(ptent)) {
mark_page_accessed(page);
file_rss--;
}
- page_remove_rmap(page);
+ page_remove_rmap(page, vma);
tlb_remove_page(tlb, page);
continue;
}
continue;
if (!pte_file(ptent))
free_swap_and_cache(pte_to_swp_entry(ptent));
- pte_clear_full(mm, addr, pte, tlb->fullmm);
+ pte_clear_not_present_full(mm, addr, pte, tlb->fullmm);
} while (pte++, addr += PAGE_SIZE, (addr != end && *zap_work > 0));
add_mm_rss(mm, file_rss, anon_rss);
+ arch_leave_lazy_mmu_mode();
pte_unmap_unlock(pte - 1, ptl);
return addr;
default:
BUG();
}
+ cond_resched();
}
if (pages) {
pages[i] = page;
{
pte_t *pte;
spinlock_t *ptl;
+ int err = 0;
pte = pte_alloc_map_lock(mm, pmd, addr, &ptl);
if (!pte)
- return -ENOMEM;
+ return -EAGAIN;
+ arch_enter_lazy_mmu_mode();
do {
struct page *page = ZERO_PAGE(addr);
pte_t zero_pte = pte_wrprotect(mk_pte(page, prot));
+
+ if (unlikely(!pte_none(*pte))) {
+ err = -EEXIST;
+ pte++;
+ break;
+ }
page_cache_get(page);
page_add_file_rmap(page);
inc_mm_counter(mm, file_rss);
- BUG_ON(!pte_none(*pte));
set_pte_at(mm, addr, pte, zero_pte);
} while (pte++, addr += PAGE_SIZE, addr != end);
+ arch_leave_lazy_mmu_mode();
pte_unmap_unlock(pte - 1, ptl);
- return 0;
+ return err;
}
static inline int zeromap_pmd_range(struct mm_struct *mm, pud_t *pud,
{
pmd_t *pmd;
unsigned long next;
+ int err;
pmd = pmd_alloc(mm, pud, addr);
if (!pmd)
- return -ENOMEM;
+ return -EAGAIN;
do {
next = pmd_addr_end(addr, end);
- if (zeromap_pte_range(mm, pmd, addr, next, prot))
- return -ENOMEM;
+ err = zeromap_pte_range(mm, pmd, addr, next, prot);
+ if (err)
+ break;
} while (pmd++, addr = next, addr != end);
- return 0;
+ return err;
}
static inline int zeromap_pud_range(struct mm_struct *mm, pgd_t *pgd,
{
pud_t *pud;
unsigned long next;
+ int err;
pud = pud_alloc(mm, pgd, addr);
if (!pud)
- return -ENOMEM;
+ return -EAGAIN;
do {
next = pud_addr_end(addr, end);
- if (zeromap_pmd_range(mm, pud, addr, next, prot))
- return -ENOMEM;
+ err = zeromap_pmd_range(mm, pud, addr, next, prot);
+ if (err)
+ break;
} while (pud++, addr = next, addr != end);
- return 0;
+ return err;
}
int zeromap_page_range(struct vm_area_struct *vma,
pte = pte_alloc_map_lock(mm, pmd, addr, &ptl);
if (!pte)
return -ENOMEM;
+ arch_enter_lazy_mmu_mode();
do {
BUG_ON(!pte_none(*pte));
set_pte_at(mm, addr, pte, pfn_pte(pfn, prot));
pfn++;
} while (pte++, addr += PAGE_SIZE, addr != end);
+ arch_leave_lazy_mmu_mode();
pte_unmap_unlock(pte - 1, ptl);
return 0;
}
return pte;
}
-static inline void cow_user_page(struct page *dst, struct page *src, unsigned long va)
+static inline void cow_user_page(struct page *dst, struct page *src, unsigned long va, struct vm_area_struct *vma)
{
/*
* If the source page was a PFN mapping, we don't have
if (__copy_from_user_inatomic(kaddr, uaddr, PAGE_SIZE))
memset(kaddr, 0, PAGE_SIZE);
kunmap_atomic(kaddr, KM_USER0);
+ flush_dcache_page(dst);
return;
-
+
}
- copy_user_highpage(dst, src, va);
+ copy_user_highpage(dst, src, va, vma);
}
/*
new_page = alloc_page_vma(GFP_HIGHUSER, vma, address);
if (!new_page)
goto oom;
- cow_user_page(new_page, old_page, address);
+ cow_user_page(new_page, old_page, address, vma);
}
/*
page_table = pte_offset_map_lock(mm, pmd, address, &ptl);
if (likely(pte_same(*page_table, orig_pte))) {
if (old_page) {
- page_remove_rmap(old_page);
+ page_remove_rmap(old_page, vma);
if (!PageAnon(old_page)) {
dec_mm_counter(mm, file_rss);
inc_mm_counter(mm, anon_rss);
entry = mk_pte(new_page, vma->vm_page_prot);
entry = maybe_mkwrite(pte_mkdirty(entry), vma);
lazy_mmu_prot_update(entry);
- ptep_establish(vma, address, page_table, entry);
+ /*
+ * Clear the pte entry and flush it first, before updating the
+ * pte with the new entry. This will avoid a race condition
+ * seen in the presence of one thread doing SMC and another
+ * thread doing COW.
+ */
+ ptep_clear_flush(vma, address, page_table);
+ set_pte_at(mm, address, page_table, entry);
update_mmu_cache(vma, address, entry);
lru_cache_add_active(new_page);
page_add_new_anon_rmap(new_page, vma, address);
return 0;
}
-EXPORT_UNUSED_SYMBOL(vmtruncate_range); /* June 2006 */
/**
* swapin_readahead - swap in pages in hope we need them soon
delayacct_set_flag(DELAYACCT_PF_SWAPIN);
page = lookup_swap_cache(entry);
if (!page) {
+ grab_swap_token(); /* Contend for token _before_ read-in */
swapin_readahead(entry, address, vma);
page = read_swap_cache_async(entry, vma, address);
if (!page) {
/* Had to read the page from swap area: Major fault */
ret = VM_FAULT_MAJOR;
count_vm_event(PGMAJFAULT);
- grab_swap_token();
}
delayacct_clear_flag(DELAYACCT_PF_SWAPIN);
* after the next truncate_count read.
*/
- /* no page was available -- either SIGBUS or OOM */
- if (new_page == NOPAGE_SIGBUS)
+ /* no page was available -- either SIGBUS, OOM or REFAULT */
+ if (unlikely(new_page == NOPAGE_SIGBUS))
return VM_FAULT_SIGBUS;
- if (new_page == NOPAGE_OOM)
+ else if (unlikely(new_page == NOPAGE_OOM))
return VM_FAULT_OOM;
+ else if (unlikely(new_page == NOPAGE_REFAULT))
+ return VM_FAULT_MINOR;
/*
* Should we do an early C-O-W break?
page = alloc_page_vma(GFP_HIGHUSER, vma, address);
if (!page)
goto oom;
- copy_user_highpage(page, new_page, address);
+ copy_user_highpage(page, new_page, address, vma);
page_cache_release(new_page);
new_page = page;
anon = 1;
}
#endif /* __HAVE_ARCH_GATE_AREA */
+
+/*
+ * Access another process' address space.
+ * Source/target buffer must be kernel space,
+ * Do not walk the page table directly, use get_user_pages
+ */
+int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write)
+{
+ struct mm_struct *mm;
+ struct vm_area_struct *vma;
+ struct page *page;
+ void *old_buf = buf;
+
+ mm = get_task_mm(tsk);
+ if (!mm)
+ return 0;
+
+ down_read(&mm->mmap_sem);
+ /* ignore errors, just check how much was sucessfully transfered */
+ while (len) {
+ int bytes, ret, offset;
+ void *maddr;
+
+ ret = get_user_pages(tsk, mm, addr, 1,
+ write, 1, &page, &vma);
+ if (ret <= 0)
+ break;
+
+ bytes = len;
+ offset = addr & (PAGE_SIZE-1);
+ if (bytes > PAGE_SIZE-offset)
+ bytes = PAGE_SIZE-offset;
+
+ maddr = kmap(page);
+ if (write) {
+ copy_to_user_page(vma, page, addr,
+ maddr + offset, buf, bytes);
+ set_page_dirty_lock(page);
+ } else {
+ copy_from_user_page(vma, page, addr,
+ buf, maddr + offset, bytes);
+ }
+ kunmap(page);
+ page_cache_release(page);
+ len -= bytes;
+ buf += bytes;
+ addr += bytes;
+ }
+ up_read(&mm->mmap_sem);
+ mmput(mm);
+
+ return buf - old_buf;
+}