diff --git a/arch/ppc64/kernel/vdso.c b/arch/ppc64/kernel/vdso.c index efa985f05aca2ebfe45be32ff4cd1e6b339ce1d8..4aacf521e3e445466e4133955bfe2b5accbf09b3 100644 --- a/arch/ppc64/kernel/vdso.c +++ b/arch/ppc64/kernel/vdso.c @@ -176,13 +176,13 @@ static struct page * vdso_vma_nopage(struct vm_area_struct * vma, return NOPAGE_SIGBUS; /* - * Last page is systemcfg, special handling here, no get_page() a - * this is a reserved page + * Last page is systemcfg. */ if ((vma->vm_end - address) <= PAGE_SIZE) - return virt_to_page(systemcfg); + pg = virt_to_page(systemcfg); + else + pg = virt_to_page(vbase + offset); - pg = virt_to_page(vbase + offset); get_page(pg); DBG(" ->page count: %d\n", page_count(pg)); @@ -259,7 +259,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int executable_stack) * gettimeofday will be totally dead. It's fine to use that for setting * breakpoints in the vDSO code pages though */ - vma->vm_flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC; + vma->vm_flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC | VM_RESERVED; vma->vm_flags |= mm->def_flags; vma->vm_page_prot = protection_map[vma->vm_flags & 0x7]; vma->vm_ops = &vdso_vmops; @@ -603,6 +603,8 @@ void __init vdso_init(void) ClearPageReserved(pg); get_page(pg); } + + get_page(virt_to_page(systemcfg)); } int in_gate_area_no_task(unsigned long addr) diff --git a/arch/sparc/mm/generic.c b/arch/sparc/mm/generic.c index 20ccb957fb7795118b5f06b21d7c5649423e72b4..659c9a71f867fd959b9475df284e4d4e78bbf7e6 100644 --- a/arch/sparc/mm/generic.c +++ b/arch/sparc/mm/generic.c @@ -73,6 +73,9 @@ int io_remap_pfn_range(struct vm_area_struct *vma, unsigned long from, int space = GET_IOSPACE(pfn); unsigned long offset = GET_PFN(pfn) << PAGE_SHIFT; + /* See comment in mm/memory.c remap_pfn_range */ + vma->vm_flags |= VM_IO | VM_RESERVED; + prot = __pgprot(pg_iobits); offset -= from; dir = pgd_offset(mm, from); diff --git a/arch/sparc64/mm/generic.c b/arch/sparc64/mm/generic.c index c954d91f01d0463aa75f607c393f1c7f4fd7dfcb..afc01cec701f56f7cb539b03a9a9f0e829c35256 100644 --- a/arch/sparc64/mm/generic.c +++ b/arch/sparc64/mm/generic.c @@ -127,6 +127,9 @@ int io_remap_pfn_range(struct vm_area_struct *vma, unsigned long from, int space = GET_IOSPACE(pfn); unsigned long offset = GET_PFN(pfn) << PAGE_SHIFT; + /* See comment in mm/memory.c remap_pfn_range */ + vma->vm_flags |= VM_IO | VM_RESERVED; + prot = __pgprot(pg_iobits); offset -= from; dir = pgd_offset(mm, from); diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 861e51375d70c541609105548e25d507df7f00fc..2d30b46806bf30a3d65f9ba1b05672b8143e5c20 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -1886,13 +1886,17 @@ st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages, int i; for (i=0; i < nr_pages; i++) { - if (dirtied && !PageReserved(sgl[i].page)) - SetPageDirty(sgl[i].page); - /* unlock_page(sgl[i].page); */ + struct page *page = sgl[i].page; + + /* XXX: just for debug. Remove when PageReserved is removed */ + BUG_ON(PageReserved(page)); + if (dirtied) + SetPageDirty(page); + /* unlock_page(page); */ /* FIXME: cache flush missing for rw==READ * FIXME: call the correct reference counting function */ - page_cache_release(sgl[i].page); + page_cache_release(page); } return 0; diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c index 5eb54d8019b46c3afb6dd9e264676a3e8a03d376..da9766283bd7d0b9125d6cc1146f74860766c40b 100644 --- a/drivers/scsi/st.c +++ b/drivers/scsi/st.c @@ -4526,12 +4526,16 @@ static int sgl_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_p int i; for (i=0; i < nr_pages; i++) { - if (dirtied && !PageReserved(sgl[i].page)) - SetPageDirty(sgl[i].page); + struct page *page = sgl[i].page; + + /* XXX: just for debug. Remove when PageReserved is removed */ + BUG_ON(PageReserved(page)); + if (dirtied) + SetPageDirty(page); /* FIXME: cache flush missing for rw==READ * FIXME: call the correct reference counting function */ - page_cache_release(sgl[i].page); + page_cache_release(page); } return 0; diff --git a/fs/direct-io.c b/fs/direct-io.c index 0d06097bc995f93cd0074c424cbf24d221b80490..3931e7f1e6bf34a53caad0ced825942b14c18e1b 100644 --- a/fs/direct-io.c +++ b/fs/direct-io.c @@ -162,6 +162,7 @@ static int dio_refill_pages(struct dio *dio) up_read(¤t->mm->mmap_sem); if (ret < 0 && dio->blocks_available && (dio->rw == WRITE)) { + struct page *page = ZERO_PAGE(dio->curr_user_address); /* * A memory fault, but the filesystem has some outstanding * mapped blocks. We need to use those blocks up to avoid @@ -169,7 +170,8 @@ static int dio_refill_pages(struct dio *dio) */ if (dio->page_errors == 0) dio->page_errors = ret; - dio->pages[0] = ZERO_PAGE(dio->curr_user_address); + page_cache_get(page); + dio->pages[0] = page; dio->head = 0; dio->tail = 1; ret = 0; diff --git a/include/linux/mm.h b/include/linux/mm.h index 0c64484d8ae0ca61da9a07c7b46d6787c8294d6b..da42093250c3927f5fbeb0eb3391f928b2a0e0d9 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -157,7 +157,7 @@ extern unsigned int kobjsize(const void *objp); #define VM_DONTCOPY 0x00020000 /* Do not copy this vma on fork */ #define VM_DONTEXPAND 0x00040000 /* Cannot expand with mremap() */ -#define VM_RESERVED 0x00080000 /* Don't unmap it from swap_out */ +#define VM_RESERVED 0x00080000 /* Pages managed in a special way */ #define VM_ACCOUNT 0x00100000 /* Is a VM accounted object */ #define VM_HUGETLB 0x00400000 /* Huge TLB Page VM */ #define VM_NONLINEAR 0x00800000 /* Is non-linear (remap_file_pages) */ @@ -338,7 +338,7 @@ static inline void get_page(struct page *page) static inline void put_page(struct page *page) { - if (!PageReserved(page) && put_page_testzero(page)) + if (put_page_testzero(page)) __page_cache_release(page); } @@ -723,6 +723,7 @@ void install_arg_page(struct vm_area_struct *, struct page *, unsigned long); int get_user_pages(struct task_struct *tsk, struct mm_struct *mm, unsigned long start, int len, int write, int force, struct page **pages, struct vm_area_struct **vmas); +void print_bad_pte(struct vm_area_struct *, pte_t, unsigned long); int __set_page_dirty_buffers(struct page *page); int __set_page_dirty_nobuffers(struct page *page); diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c index 10bc5ec496d72a25e70b42785cfaee781312dddb..016504ccfccf4e6e37d97015d0f4026a51d52299 100644 --- a/kernel/power/swsusp.c +++ b/kernel/power/swsusp.c @@ -578,15 +578,23 @@ static int save_highmem_zone(struct zone *zone) continue; page = pfn_to_page(pfn); /* - * This condition results from rvmalloc() sans vmalloc_32() - * and architectural memory reservations. This should be - * corrected eventually when the cases giving rise to this - * are better understood. + * PageReserved results from rvmalloc() sans vmalloc_32() + * and architectural memory reservations. + * + * rvmalloc should not cause this, because all implementations + * appear to always be using vmalloc_32 on architectures with + * highmem. This is a good thing, because we would like to save + * rvmalloc pages. + * + * It appears to be triggered by pages which do not point to + * valid memory (see arch/i386/mm/init.c:one_highpage_init(), + * which sets PageReserved if the page does not point to valid + * RAM. + * + * XXX: must remove usage of PageReserved! */ - if (PageReserved(page)) { - printk("highmem reserved page?!\n"); + if (PageReserved(page)) continue; - } BUG_ON(PageNosave(page)); if (PageNosaveFree(page)) continue; @@ -672,10 +680,9 @@ static int saveable(struct zone * zone, unsigned long * zone_pfn) return 0; page = pfn_to_page(pfn); - BUG_ON(PageReserved(page) && PageNosave(page)); if (PageNosave(page)) return 0; - if (PageReserved(page) && pfn_is_nosave(pfn)) { + if (pfn_is_nosave(pfn)) { pr_debug("[nosave pfn 0x%lx]", pfn); return 0; } diff --git a/mm/bootmem.c b/mm/bootmem.c index a58699b6579e1fc6364aaea564f2a26e78a0b700..e8c567177dcf83e0b8d7352c581c0565c400844c 100644 --- a/mm/bootmem.c +++ b/mm/bootmem.c @@ -305,6 +305,7 @@ static unsigned long __init free_all_bootmem_core(pg_data_t *pgdat) if (j + 16 < BITS_PER_LONG) prefetchw(page + j + 16); __ClearPageReserved(page + j); + set_page_count(page + j, 0); } __free_pages(page, order); i += BITS_PER_LONG; diff --git a/mm/filemap_xip.c b/mm/filemap_xip.c index 8c199f537732088310c0e490cebe92c7414076bb..9354ee279b1345051bf686a336b58447b4810686 100644 --- a/mm/filemap_xip.c +++ b/mm/filemap_xip.c @@ -174,6 +174,7 @@ __xip_unmap (struct address_space * mapping, unsigned long address; pte_t *pte; pte_t pteval; + struct page *page = ZERO_PAGE(address); spin_lock(&mapping->i_mmap_lock); vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) { @@ -185,15 +186,17 @@ __xip_unmap (struct address_space * mapping, * We need the page_table_lock to protect us from page faults, * munmap, fork, etc... */ - pte = page_check_address(ZERO_PAGE(address), mm, - address); + pte = page_check_address(page, mm, address); if (!IS_ERR(pte)) { /* Nuke the page table entry. */ flush_cache_page(vma, address, pte_pfn(*pte)); pteval = ptep_clear_flush(vma, address, pte); + page_remove_rmap(page); + dec_mm_counter(mm, file_rss); BUG_ON(pte_dirty(pteval)); pte_unmap(pte); spin_unlock(&mm->page_table_lock); + page_cache_release(page); } } spin_unlock(&mapping->i_mmap_lock); @@ -228,7 +231,7 @@ xip_file_nopage(struct vm_area_struct * area, page = mapping->a_ops->get_xip_page(mapping, pgoff*(PAGE_SIZE/512), 0); if (!IS_ERR(page)) { - return page; + goto out; } if (PTR_ERR(page) != -ENODATA) return NULL; @@ -249,6 +252,8 @@ xip_file_nopage(struct vm_area_struct * area, page = ZERO_PAGE(address); } +out: + page_cache_get(page); return page; } diff --git a/mm/fremap.c b/mm/fremap.c index fd7f2a17ff3e49bada9aa1d7c18febe56a9cda03..224cc1598b354bd4d12659f31c682ec09ecf9aa9 100644 --- a/mm/fremap.c +++ b/mm/fremap.c @@ -29,19 +29,20 @@ static inline void zap_pte(struct mm_struct *mm, struct vm_area_struct *vma, return; if (pte_present(pte)) { unsigned long pfn = pte_pfn(pte); + struct page *page; flush_cache_page(vma, addr, pfn); pte = ptep_clear_flush(vma, addr, ptep); - if (pfn_valid(pfn)) { - struct page *page = pfn_to_page(pfn); - if (!PageReserved(page)) { - if (pte_dirty(pte)) - set_page_dirty(page); - page_remove_rmap(page); - page_cache_release(page); - dec_mm_counter(mm, file_rss); - } + if (unlikely(!pfn_valid(pfn))) { + print_bad_pte(vma, pte, addr); + return; } + page = pfn_to_page(pfn); + if (pte_dirty(pte)) + set_page_dirty(page); + page_remove_rmap(page); + page_cache_release(page); + dec_mm_counter(mm, file_rss); } else { if (!pte_file(pte)) free_swap_and_cache(pte_to_swp_entry(pte)); @@ -65,6 +66,8 @@ int install_page(struct mm_struct *mm, struct vm_area_struct *vma, pgd_t *pgd; pte_t pte_val; + BUG_ON(vma->vm_flags & VM_RESERVED); + pgd = pgd_offset(mm, addr); spin_lock(&mm->page_table_lock); @@ -125,6 +128,8 @@ int install_file_pte(struct mm_struct *mm, struct vm_area_struct *vma, pgd_t *pgd; pte_t pte_val; + BUG_ON(vma->vm_flags & VM_RESERVED); + pgd = pgd_offset(mm, addr); spin_lock(&mm->page_table_lock); diff --git a/mm/madvise.c b/mm/madvise.c index 20e075d1c64c9c64674e5fc418c6643418931661..17aaf3e1644983a5a4fac14bef8f009f71fe866c 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -126,7 +126,7 @@ static long madvise_dontneed(struct vm_area_struct * vma, unsigned long start, unsigned long end) { *prev = vma; - if ((vma->vm_flags & VM_LOCKED) || is_vm_hugetlb_page(vma)) + if (vma->vm_flags & (VM_LOCKED|VM_HUGETLB|VM_RESERVED)) return -EINVAL; if (unlikely(vma->vm_flags & VM_NONLINEAR)) { diff --git a/mm/memory.c b/mm/memory.c index da642b5528fab0ccd8d44611d6b0fcd27cd65474..e83f9440bb66b2b8ed7bffaddfaa97d55265c623 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -342,6 +342,23 @@ static inline void add_mm_rss(struct mm_struct *mm, int file_rss, int anon_rss) #define NO_RSS 2 /* Increment neither file_rss nor anon_rss */ +/* + * This function is called to print an error when a pte in a + * !VM_RESERVED region is found pointing to an invalid pfn (which + * is an error. + * + * The calling function must still handle the error. + */ +void print_bad_pte(struct vm_area_struct *vma, pte_t pte, unsigned long vaddr) +{ + printk(KERN_ERR "Bad pte = %08llx, process = %s, " + "vm_flags = %lx, vaddr = %lx\n", + (long long)pte_val(pte), + (vma->vm_mm == current->mm ? current->comm : "???"), + vma->vm_flags, vaddr); + dump_stack(); +} + /* * copy one vm_area from one task to the other. Assumes the page tables * already present in the new task to be cleared in the whole range @@ -353,9 +370,10 @@ static inline void add_mm_rss(struct mm_struct *mm, int file_rss, int anon_rss) static inline int copy_one_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm, - pte_t *dst_pte, pte_t *src_pte, unsigned long vm_flags, + pte_t *dst_pte, pte_t *src_pte, struct vm_area_struct *vma, unsigned long addr) { + unsigned long vm_flags = vma->vm_flags; pte_t pte = *src_pte; struct page *page; unsigned long pfn; @@ -375,18 +393,22 @@ copy_one_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm, goto out_set_pte; } + /* If the region is VM_RESERVED, the mapping is not + * mapped via rmap - duplicate the pte as is. + */ + if (vm_flags & VM_RESERVED) + goto out_set_pte; + pfn = pte_pfn(pte); - /* the pte points outside of valid memory, the - * mapping is assumed to be good, meaningful - * and not mapped via rmap - duplicate the - * mapping as is. + /* If the pte points outside of valid memory but + * the region is not VM_RESERVED, we have a problem. */ - page = NULL; - if (pfn_valid(pfn)) - page = pfn_to_page(pfn); + if (unlikely(!pfn_valid(pfn))) { + print_bad_pte(vma, pte, addr); + goto out_set_pte; /* try to do something sane */ + } - if (!page || PageReserved(page)) - goto out_set_pte; + page = pfn_to_page(pfn); /* * If it's a COW mapping, write protect it both @@ -418,7 +440,6 @@ static int copy_pte_range(struct mm_struct *dst_mm, struct mm_struct *src_mm, unsigned long addr, unsigned long end) { pte_t *src_pte, *dst_pte; - unsigned long vm_flags = vma->vm_flags; int progress = 0; int rss[NO_RSS+1], anon; @@ -446,8 +467,7 @@ static int copy_pte_range(struct mm_struct *dst_mm, struct mm_struct *src_mm, progress++; continue; } - anon = copy_one_pte(dst_mm, src_mm, dst_pte, src_pte, - vm_flags, addr); + anon = copy_one_pte(dst_mm, src_mm, dst_pte, src_pte, vma,addr); rss[anon]++; progress += 8; } while (dst_pte++, src_pte++, addr += PAGE_SIZE, addr != end); @@ -541,10 +561,12 @@ int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm, return 0; } -static void zap_pte_range(struct mmu_gather *tlb, pmd_t *pmd, +static void zap_pte_range(struct mmu_gather *tlb, + struct vm_area_struct *vma, pmd_t *pmd, unsigned long addr, unsigned long end, struct zap_details *details) { + struct mm_struct *mm = tlb->mm; pte_t *pte; int file_rss = 0; int anon_rss = 0; @@ -556,11 +578,12 @@ static void zap_pte_range(struct mmu_gather *tlb, pmd_t *pmd, continue; if (pte_present(ptent)) { struct page *page = NULL; - unsigned long pfn = pte_pfn(ptent); - if (pfn_valid(pfn)) { - page = pfn_to_page(pfn); - if (PageReserved(page)) - page = NULL; + if (!(vma->vm_flags & VM_RESERVED)) { + unsigned long pfn = pte_pfn(ptent); + if (unlikely(!pfn_valid(pfn))) + print_bad_pte(vma, ptent, addr); + else + page = pfn_to_page(pfn); } if (unlikely(details) && page) { /* @@ -580,7 +603,7 @@ static void zap_pte_range(struct mmu_gather *tlb, pmd_t *pmd, page->index > details->last_index)) continue; } - ptent = ptep_get_and_clear_full(tlb->mm, addr, pte, + ptent = ptep_get_and_clear_full(mm, addr, pte, tlb->fullmm); tlb_remove_tlb_entry(tlb, pte, addr); if (unlikely(!page)) @@ -588,7 +611,7 @@ static void zap_pte_range(struct mmu_gather *tlb, pmd_t *pmd, if (unlikely(details) && details->nonlinear_vma && linear_page_index(details->nonlinear_vma, addr) != page->index) - set_pte_at(tlb->mm, addr, pte, + set_pte_at(mm, addr, pte, pgoff_to_pte(page->index)); if (PageAnon(page)) anon_rss++; @@ -611,14 +634,15 @@ static void zap_pte_range(struct mmu_gather *tlb, pmd_t *pmd, continue; if (!pte_file(ptent)) free_swap_and_cache(pte_to_swp_entry(ptent)); - pte_clear_full(tlb->mm, addr, pte, tlb->fullmm); + pte_clear_full(mm, addr, pte, tlb->fullmm); } while (pte++, addr += PAGE_SIZE, addr != end); - add_mm_rss(tlb->mm, -file_rss, -anon_rss); + add_mm_rss(mm, -file_rss, -anon_rss); pte_unmap(pte - 1); } -static inline void zap_pmd_range(struct mmu_gather *tlb, pud_t *pud, +static inline void zap_pmd_range(struct mmu_gather *tlb, + struct vm_area_struct *vma, pud_t *pud, unsigned long addr, unsigned long end, struct zap_details *details) { @@ -630,11 +654,12 @@ static inline void zap_pmd_range(struct mmu_gather *tlb, pud_t *pud, next = pmd_addr_end(addr, end); if (pmd_none_or_clear_bad(pmd)) continue; - zap_pte_range(tlb, pmd, addr, next, details); + zap_pte_range(tlb, vma, pmd, addr, next, details); } while (pmd++, addr = next, addr != end); } -static inline void zap_pud_range(struct mmu_gather *tlb, pgd_t *pgd, +static inline void zap_pud_range(struct mmu_gather *tlb, + struct vm_area_struct *vma, pgd_t *pgd, unsigned long addr, unsigned long end, struct zap_details *details) { @@ -646,7 +671,7 @@ static inline void zap_pud_range(struct mmu_gather *tlb, pgd_t *pgd, next = pud_addr_end(addr, end); if (pud_none_or_clear_bad(pud)) continue; - zap_pmd_range(tlb, pud, addr, next, details); + zap_pmd_range(tlb, vma, pud, addr, next, details); } while (pud++, addr = next, addr != end); } @@ -667,7 +692,7 @@ static void unmap_page_range(struct mmu_gather *tlb, struct vm_area_struct *vma, next = pgd_addr_end(addr, end); if (pgd_none_or_clear_bad(pgd)) continue; - zap_pud_range(tlb, pgd, addr, next, details); + zap_pud_range(tlb, vma, pgd, addr, next, details); } while (pgd++, addr = next, addr != end); tlb_end_vma(tlb, vma); } @@ -967,7 +992,7 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm, continue; } - if (!vma || (vma->vm_flags & VM_IO) + if (!vma || (vma->vm_flags & (VM_IO | VM_RESERVED)) || !(flags & vma->vm_flags)) return i ? : -EFAULT; @@ -1027,8 +1052,7 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm, if (pages) { pages[i] = page; flush_dcache_page(page); - if (!PageReserved(page)) - page_cache_get(page); + page_cache_get(page); } if (vmas) vmas[i] = vma; @@ -1051,7 +1075,11 @@ static int zeromap_pte_range(struct mm_struct *mm, pmd_t *pmd, if (!pte) return -ENOMEM; do { - pte_t zero_pte = pte_wrprotect(mk_pte(ZERO_PAGE(addr), prot)); + struct page *page = ZERO_PAGE(addr); + pte_t zero_pte = pte_wrprotect(mk_pte(page, prot)); + 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); @@ -1132,8 +1160,7 @@ static int remap_pte_range(struct mm_struct *mm, pmd_t *pmd, return -ENOMEM; do { BUG_ON(!pte_none(*pte)); - if (!pfn_valid(pfn) || PageReserved(pfn_to_page(pfn))) - set_pte_at(mm, addr, pte, pfn_pte(pfn, prot)); + set_pte_at(mm, addr, pte, pfn_pte(pfn, prot)); pfn++; } while (pte++, addr += PAGE_SIZE, addr != end); pte_unmap(pte - 1); @@ -1195,8 +1222,8 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr, * rest of the world about it: * VM_IO tells people not to look at these pages * (accesses can have side effects). - * VM_RESERVED tells swapout not to try to touch - * this region. + * VM_RESERVED tells the core MM not to "manage" these pages + * (e.g. refcount, mapcount, try to swap them out). */ vma->vm_flags |= VM_IO | VM_RESERVED; @@ -1256,11 +1283,13 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma, pte_t entry; int ret = VM_FAULT_MINOR; + BUG_ON(vma->vm_flags & VM_RESERVED); + if (unlikely(!pfn_valid(pfn))) { /* * Page table corrupted: show pte and kill process. */ - pte_ERROR(orig_pte); + print_bad_pte(vma, orig_pte, address); ret = VM_FAULT_OOM; goto unlock; } @@ -1284,8 +1313,7 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma, /* * Ok, we need to copy. Oh, well.. */ - if (!PageReserved(old_page)) - page_cache_get(old_page); + page_cache_get(old_page); pte_unmap(page_table); spin_unlock(&mm->page_table_lock); @@ -1308,14 +1336,10 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma, spin_lock(&mm->page_table_lock); page_table = pte_offset_map(pmd, address); if (likely(pte_same(*page_table, orig_pte))) { - if (PageReserved(old_page)) + page_remove_rmap(old_page); + if (!PageAnon(old_page)) { inc_mm_counter(mm, anon_rss); - else { - page_remove_rmap(old_page); - if (!PageAnon(old_page)) { - inc_mm_counter(mm, anon_rss); - dec_mm_counter(mm, file_rss); - } + dec_mm_counter(mm, file_rss); } flush_cache_page(vma, address, pfn); entry = mk_pte(new_page, vma->vm_page_prot); @@ -1769,14 +1793,13 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long address, pte_t *page_table, pmd_t *pmd, int write_access) { + struct page *page = ZERO_PAGE(addr); pte_t entry; /* Mapping of ZERO_PAGE - vm_page_prot is readonly */ - entry = mk_pte(ZERO_PAGE(addr), vma->vm_page_prot); + entry = mk_pte(page, vma->vm_page_prot); if (write_access) { - struct page *page; - /* Allocate our own private page. */ pte_unmap(page_table); spin_unlock(&mm->page_table_lock); @@ -1800,6 +1823,10 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma, lru_cache_add_active(page); SetPageReferenced(page); page_add_anon_rmap(page, vma, address); + } else { + inc_mm_counter(mm, file_rss); + page_add_file_rmap(page); + page_cache_get(page); } set_pte_at(mm, address, page_table, entry); @@ -1916,7 +1943,7 @@ static int do_no_page(struct mm_struct *mm, struct vm_area_struct *vma, inc_mm_counter(mm, anon_rss); lru_cache_add_active(new_page); page_add_anon_rmap(new_page, vma, address); - } else if (!PageReserved(new_page)) { + } else if (!(vma->vm_flags & VM_RESERVED)) { inc_mm_counter(mm, file_rss); page_add_file_rmap(new_page); } @@ -1957,7 +1984,7 @@ static int do_file_page(struct mm_struct *mm, struct vm_area_struct *vma, /* * Page table corrupted: show pte and kill process. */ - pte_ERROR(orig_pte); + print_bad_pte(vma, orig_pte, address); return VM_FAULT_OOM; } /* We can then assume vm->vm_ops && vma->vm_ops->populate */ @@ -2232,7 +2259,7 @@ static int __init gate_vma_init(void) gate_vma.vm_start = FIXADDR_USER_START; gate_vma.vm_end = FIXADDR_USER_END; gate_vma.vm_page_prot = PAGE_READONLY; - gate_vma.vm_flags = 0; + gate_vma.vm_flags = VM_RESERVED; return 0; } __initcall(gate_vma_init); diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 43b1199af591303c74fbb56e82b43b6d8fca2d6e..11d824f282f10fa04743642b75f30270316be250 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -223,13 +223,13 @@ static struct mempolicy *mpol_new(int mode, nodemask_t *nodes) } /* Ensure all existing pages follow the policy. */ -static int check_pte_range(struct mm_struct *mm, pmd_t *pmd, +static int check_pte_range(struct vm_area_struct *vma, pmd_t *pmd, unsigned long addr, unsigned long end, nodemask_t *nodes) { pte_t *orig_pte; pte_t *pte; - spin_lock(&mm->page_table_lock); + spin_lock(&vma->vm_mm->page_table_lock); orig_pte = pte = pte_offset_map(pmd, addr); do { unsigned long pfn; @@ -238,18 +238,20 @@ static int check_pte_range(struct mm_struct *mm, pmd_t *pmd, if (!pte_present(*pte)) continue; pfn = pte_pfn(*pte); - if (!pfn_valid(pfn)) + if (!pfn_valid(pfn)) { + print_bad_pte(vma, *pte, addr); continue; + } nid = pfn_to_nid(pfn); if (!node_isset(nid, *nodes)) break; } while (pte++, addr += PAGE_SIZE, addr != end); pte_unmap(orig_pte); - spin_unlock(&mm->page_table_lock); + spin_unlock(&vma->vm_mm->page_table_lock); return addr != end; } -static inline int check_pmd_range(struct mm_struct *mm, pud_t *pud, +static inline int check_pmd_range(struct vm_area_struct *vma, pud_t *pud, unsigned long addr, unsigned long end, nodemask_t *nodes) { pmd_t *pmd; @@ -260,13 +262,13 @@ static inline int check_pmd_range(struct mm_struct *mm, pud_t *pud, next = pmd_addr_end(addr, end); if (pmd_none_or_clear_bad(pmd)) continue; - if (check_pte_range(mm, pmd, addr, next, nodes)) + if (check_pte_range(vma, pmd, addr, next, nodes)) return -EIO; } while (pmd++, addr = next, addr != end); return 0; } -static inline int check_pud_range(struct mm_struct *mm, pgd_t *pgd, +static inline int check_pud_range(struct vm_area_struct *vma, pgd_t *pgd, unsigned long addr, unsigned long end, nodemask_t *nodes) { pud_t *pud; @@ -277,24 +279,24 @@ static inline int check_pud_range(struct mm_struct *mm, pgd_t *pgd, next = pud_addr_end(addr, end); if (pud_none_or_clear_bad(pud)) continue; - if (check_pmd_range(mm, pud, addr, next, nodes)) + if (check_pmd_range(vma, pud, addr, next, nodes)) return -EIO; } while (pud++, addr = next, addr != end); return 0; } -static inline int check_pgd_range(struct mm_struct *mm, +static inline int check_pgd_range(struct vm_area_struct *vma, unsigned long addr, unsigned long end, nodemask_t *nodes) { pgd_t *pgd; unsigned long next; - pgd = pgd_offset(mm, addr); + pgd = pgd_offset(vma->vm_mm, addr); do { next = pgd_addr_end(addr, end); if (pgd_none_or_clear_bad(pgd)) continue; - if (check_pud_range(mm, pgd, addr, next, nodes)) + if (check_pud_range(vma, pgd, addr, next, nodes)) return -EIO; } while (pgd++, addr = next, addr != end); return 0; @@ -311,6 +313,8 @@ check_range(struct mm_struct *mm, unsigned long start, unsigned long end, first = find_vma(mm, start); if (!first) return ERR_PTR(-EFAULT); + if (first->vm_flags & VM_RESERVED) + return ERR_PTR(-EACCES); prev = NULL; for (vma = first; vma && vma->vm_start < end; vma = vma->vm_next) { if (!vma->vm_next && vma->vm_end < end) @@ -323,8 +327,7 @@ check_range(struct mm_struct *mm, unsigned long start, unsigned long end, endvma = end; if (vma->vm_start > start) start = vma->vm_start; - err = check_pgd_range(vma->vm_mm, - start, endvma, nodes); + err = check_pgd_range(vma, start, endvma, nodes); if (err) { first = ERR_PTR(err); break; diff --git a/mm/mmap.c b/mm/mmap.c index 459b9f068ad7b13f8241f024fe779e2b26cfcff7..8a111792b8db6b22f19d8b1de8b006a48927221b 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1088,6 +1088,17 @@ unsigned long do_mmap_pgoff(struct file * file, unsigned long addr, error = file->f_op->mmap(file, vma); if (error) goto unmap_and_free_vma; + if ((vma->vm_flags & (VM_SHARED | VM_WRITE | VM_RESERVED)) + == (VM_WRITE | VM_RESERVED)) { + printk(KERN_WARNING "program %s is using MAP_PRIVATE, " + "PROT_WRITE mmap of VM_RESERVED memory, which " + "is deprecated. Please report this to " + "linux-kernel@vger.kernel.org\n",current->comm); + if (vma->vm_ops && vma->vm_ops->close) + vma->vm_ops->close(vma); + error = -EACCES; + goto unmap_and_free_vma; + } } else if (vm_flags & VM_SHARED) { error = shmem_zero_setup(vma); if (error) diff --git a/mm/mprotect.c b/mm/mprotect.c index b426f01c5e9cdb0329657076d8a2e8908e3e015a..672a76fddd5e1bc3a1c9f5f599c0ed49ffea30af 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -125,6 +125,14 @@ mprotect_fixup(struct vm_area_struct *vma, struct vm_area_struct **pprev, * a MAP_NORESERVE private mapping to writable will now reserve. */ if (newflags & VM_WRITE) { + if (oldflags & VM_RESERVED) { + BUG_ON(oldflags & VM_WRITE); + printk(KERN_WARNING "program %s is using MAP_PRIVATE, " + "PROT_WRITE mprotect of VM_RESERVED memory, " + "which is deprecated. Please report this to " + "linux-kernel@vger.kernel.org\n",current->comm); + return -EACCES; + } if (!(oldflags & (VM_ACCOUNT|VM_WRITE|VM_SHARED|VM_HUGETLB))) { charged = nrpages; if (security_vm_enough_memory(charged)) diff --git a/mm/msync.c b/mm/msync.c index 3b5f1c521d4b580896504d31778441c10d25531a..8603954860601b24807c69a5d538a7114ee6932b 100644 --- a/mm/msync.c +++ b/mm/msync.c @@ -25,6 +25,7 @@ static void msync_pte_range(struct vm_area_struct *vma, pmd_t *pmd, unsigned long addr, unsigned long end) { + struct mm_struct *mm = vma->vm_mm; pte_t *pte; int progress = 0; @@ -37,7 +38,7 @@ static void msync_pte_range(struct vm_area_struct *vma, pmd_t *pmd, if (progress >= 64) { progress = 0; if (need_resched() || - need_lockbreak(&vma->vm_mm->page_table_lock)) + need_lockbreak(&mm->page_table_lock)) break; } progress++; @@ -46,11 +47,11 @@ static void msync_pte_range(struct vm_area_struct *vma, pmd_t *pmd, if (!pte_maybe_dirty(*pte)) continue; pfn = pte_pfn(*pte); - if (!pfn_valid(pfn)) + if (unlikely(!pfn_valid(pfn))) { + print_bad_pte(vma, *pte, addr); continue; + } page = pfn_to_page(pfn); - if (PageReserved(page)) - continue; if (ptep_clear_flush_dirty(vma, addr, pte) || page_test_and_clear_dirty(page)) @@ -58,7 +59,7 @@ static void msync_pte_range(struct vm_area_struct *vma, pmd_t *pmd, progress += 3; } while (pte++, addr += PAGE_SIZE, addr != end); pte_unmap(pte - 1); - cond_resched_lock(&vma->vm_mm->page_table_lock); + cond_resched_lock(&mm->page_table_lock); if (addr != end) goto again; } @@ -102,8 +103,10 @@ static void msync_page_range(struct vm_area_struct *vma, /* For hugepages we can't go walking the page table normally, * but that's ok, hugetlbfs is memory based, so we don't need - * to do anything more on an msync() */ - if (is_vm_hugetlb_page(vma)) + * to do anything more on an msync(). + * Can't do anything with VM_RESERVED regions either. + */ + if (vma->vm_flags & (VM_HUGETLB|VM_RESERVED)) return; BUG_ON(addr >= end); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 60663232fbb23a34874f482f49a52f760f4d3ea6..0541288ebf4b1a898388a82a0b65cbb27dd5bde6 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -114,7 +114,8 @@ static void bad_page(const char *function, struct page *page) 1 << PG_reclaim | 1 << PG_slab | 1 << PG_swapcache | - 1 << PG_writeback); + 1 << PG_writeback | + 1 << PG_reserved ); set_page_count(page, 0); reset_page_mapcount(page); page->mapping = NULL; @@ -244,7 +245,6 @@ static inline int page_is_buddy(struct page *page, int order) { if (PagePrivate(page) && (page_order(page) == order) && - !PageReserved(page) && page_count(page) == 0) return 1; return 0; @@ -327,7 +327,8 @@ static inline void free_pages_check(const char *function, struct page *page) 1 << PG_reclaim | 1 << PG_slab | 1 << PG_swapcache | - 1 << PG_writeback ))) + 1 << PG_writeback | + 1 << PG_reserved ))) bad_page(function, page); if (PageDirty(page)) __ClearPageDirty(page); @@ -455,7 +456,8 @@ static void prep_new_page(struct page *page, int order) 1 << PG_reclaim | 1 << PG_slab | 1 << PG_swapcache | - 1 << PG_writeback ))) + 1 << PG_writeback | + 1 << PG_reserved ))) bad_page(__FUNCTION__, page); page->flags &= ~(1 << PG_uptodate | 1 << PG_error | @@ -1016,7 +1018,7 @@ void __pagevec_free(struct pagevec *pvec) fastcall void __free_pages(struct page *page, unsigned int order) { - if (!PageReserved(page) && put_page_testzero(page)) { + if (put_page_testzero(page)) { if (order == 0) free_hot_page(page); else @@ -1674,7 +1676,7 @@ void __init memmap_init_zone(unsigned long size, int nid, unsigned long zone, continue; page = pfn_to_page(pfn); set_page_links(page, zone, nid, pfn); - set_page_count(page, 0); + set_page_count(page, 1); reset_page_mapcount(page); SetPageReserved(page); INIT_LIST_HEAD(&page->lru); diff --git a/mm/rmap.c b/mm/rmap.c index 504757624cce720f2cd424c13d6448111c86e6ca..f69d5342ce7ff06f3180a6b2b93af00e455a34e5 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -443,8 +443,6 @@ int page_referenced(struct page *page, int is_locked, int ignore_token) void page_add_anon_rmap(struct page *page, struct vm_area_struct *vma, unsigned long address) { - BUG_ON(PageReserved(page)); - if (atomic_inc_and_test(&page->_mapcount)) { struct anon_vma *anon_vma = vma->anon_vma; @@ -468,8 +466,7 @@ void page_add_anon_rmap(struct page *page, void page_add_file_rmap(struct page *page) { BUG_ON(PageAnon(page)); - if (!pfn_valid(page_to_pfn(page)) || PageReserved(page)) - return; + BUG_ON(!pfn_valid(page_to_pfn(page))); if (atomic_inc_and_test(&page->_mapcount)) inc_page_state(nr_mapped); @@ -483,8 +480,6 @@ void page_add_file_rmap(struct page *page) */ void page_remove_rmap(struct page *page) { - BUG_ON(PageReserved(page)); - if (atomic_add_negative(-1, &page->_mapcount)) { BUG_ON(page_mapcount(page) < 0); /* @@ -640,13 +635,13 @@ static void try_to_unmap_cluster(unsigned long cursor, continue; pfn = pte_pfn(*pte); - if (!pfn_valid(pfn)) + if (unlikely(!pfn_valid(pfn))) { + print_bad_pte(vma, *pte, address); continue; + } page = pfn_to_page(pfn); BUG_ON(PageAnon(page)); - if (PageReserved(page)) - continue; if (ptep_clear_flush_young(vma, address, pte)) continue; @@ -808,7 +803,6 @@ int try_to_unmap(struct page *page) { int ret; - BUG_ON(PageReserved(page)); BUG_ON(!PageLocked(page)); if (PageAnon(page)) diff --git a/mm/shmem.c b/mm/shmem.c index 6796311a23ef5a20d4241f4ec2d5ca188679d7c9..37777f4c11f86074ce9d5cd81bd9cafb0dd6e233 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1506,8 +1506,10 @@ static void do_shmem_file_read(struct file *filp, loff_t *ppos, read_descriptor_ */ if (!offset) mark_page_accessed(page); - } else + } else { page = ZERO_PAGE(0); + page_cache_get(page); + } /* * Ok, we have the page, and it's up-to-date, so diff --git a/mm/swap.c b/mm/swap.c index 7771d2803f62a40402409733cadaebf1a72ead45..21d15f99805c96517c21927817512d749017c244 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -48,7 +48,7 @@ void put_page(struct page *page) } return; } - if (!PageReserved(page) && put_page_testzero(page)) + if (put_page_testzero(page)) __page_cache_release(page); } EXPORT_SYMBOL(put_page); @@ -215,7 +215,7 @@ void release_pages(struct page **pages, int nr, int cold) struct page *page = pages[i]; struct zone *pagezone; - if (PageReserved(page) || !put_page_testzero(page)) + if (!put_page_testzero(page)) continue; pagezone = page_zone(page); diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c index 67abebabf83e4afb1d9da5e69215adf7d3eee8ca..e97b2d162cc72f3140792ec9725bf71078011183 100644 --- a/sound/core/pcm_native.c +++ b/sound/core/pcm_native.c @@ -2949,8 +2949,7 @@ static struct page * snd_pcm_mmap_status_nopage(struct vm_area_struct *area, uns return NOPAGE_OOM; runtime = substream->runtime; page = virt_to_page(runtime->status); - if (!PageReserved(page)) - get_page(page); + get_page(page); if (type) *type = VM_FAULT_MINOR; return page; @@ -2992,8 +2991,7 @@ static struct page * snd_pcm_mmap_control_nopage(struct vm_area_struct *area, un return NOPAGE_OOM; runtime = substream->runtime; page = virt_to_page(runtime->control); - if (!PageReserved(page)) - get_page(page); + get_page(page); if (type) *type = VM_FAULT_MINOR; return page; @@ -3066,8 +3064,7 @@ static struct page *snd_pcm_mmap_data_nopage(struct vm_area_struct *area, unsign vaddr = runtime->dma_area + offset; page = virt_to_page(vaddr); } - if (!PageReserved(page)) - get_page(page); + get_page(page); if (type) *type = VM_FAULT_MINOR; return page;