userfaultfd: non-cooperative: add event for memory unmaps
When a non-cooperative userfaultfd monitor copies pages in the background, it may encounter regions that were already unmapped. Addition of UFFD_EVENT_UNMAP allows the uffd monitor to track precisely changes in the virtual memory layout. Since there might be different uffd contexts for the affected VMAs, we first should create a temporary representation for the unmap event for each uffd context and then notify them one by one to the appropriate userfault file descriptors. The event notification occurs after the mmap_sem has been released. [arnd@arndb.de: fix nommu build] Link: http://lkml.kernel.org/r/20170203165141.3665284-1-arnd@arndb.de [mhocko@suse.com: fix nommu build] Link: http://lkml.kernel.org/r/20170202091503.GA22823@dhcp22.suse.cz Link: http://lkml.kernel.org/r/1485542673-24387-3-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Pavel Emelyanov <xemul@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Mike Rapoport
Linus Torvalds
Родитель
846b1a0f1d
Коммит
897ab3e0c4
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@ -111,7 +111,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
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base = mmap_region(NULL, STACK_TOP, PAGE_SIZE,
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VM_READ|VM_WRITE|VM_EXEC|
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VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
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0);
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0, NULL);
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if (IS_ERR_VALUE(base)) {
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ret = base;
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goto out;
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@ -143,7 +143,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm,
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unsigned long addr = MEM_USER_INTRPT;
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addr = mmap_region(NULL, addr, INTRPT_SIZE,
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VM_READ|VM_EXEC|
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VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC, 0);
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VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC, 0, NULL);
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if (addr > (unsigned long) -PAGE_SIZE)
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retval = (int) addr;
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}
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@ -186,7 +186,7 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr)
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if (IS_ERR(vma)) {
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ret = PTR_ERR(vma);
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do_munmap(mm, text_start, image->size);
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do_munmap(mm, text_start, image->size, NULL);
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} else {
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current->mm->context.vdso = (void __user *)text_start;
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current->mm->context.vdso_image = image;
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@ -51,7 +51,7 @@ static unsigned long mpx_mmap(unsigned long len)
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down_write(&mm->mmap_sem);
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addr = do_mmap(NULL, 0, len, PROT_READ | PROT_WRITE,
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MAP_ANONYMOUS | MAP_PRIVATE, VM_MPX, 0, &populate);
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MAP_ANONYMOUS | MAP_PRIVATE, VM_MPX, 0, &populate, NULL);
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up_write(&mm->mmap_sem);
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if (populate)
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mm_populate(addr, populate);
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@ -893,7 +893,7 @@ static int unmap_entire_bt(struct mm_struct *mm,
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* avoid recursion, do_munmap() will check whether it comes
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* from one bounds table through VM_MPX flag.
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*/
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return do_munmap(mm, bt_addr, mpx_bt_size_bytes(mm));
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return do_munmap(mm, bt_addr, mpx_bt_size_bytes(mm), NULL);
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}
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static int try_unmap_single_bt(struct mm_struct *mm,
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2
fs/aio.c
2
fs/aio.c
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@ -512,7 +512,7 @@ static int aio_setup_ring(struct kioctx *ctx)
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ctx->mmap_base = do_mmap_pgoff(ctx->aio_ring_file, 0, ctx->mmap_size,
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PROT_READ | PROT_WRITE,
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MAP_SHARED, 0, &unused);
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MAP_SHARED, 0, &unused, NULL);
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up_write(&mm->mmap_sem);
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if (IS_ERR((void *)ctx->mmap_base)) {
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ctx->mmap_size = 0;
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@ -388,7 +388,7 @@ static int remap_oldmem_pfn_checked(struct vm_area_struct *vma,
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}
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return 0;
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fail:
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do_munmap(vma->vm_mm, from, len);
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do_munmap(vma->vm_mm, from, len, NULL);
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return -EAGAIN;
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}
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@ -481,7 +481,7 @@ static int mmap_vmcore(struct file *file, struct vm_area_struct *vma)
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return 0;
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fail:
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do_munmap(vma->vm_mm, vma->vm_start, len);
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do_munmap(vma->vm_mm, vma->vm_start, len, NULL);
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return -EAGAIN;
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}
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#else
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@ -71,6 +71,13 @@ struct userfaultfd_fork_ctx {
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struct list_head list;
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};
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struct userfaultfd_unmap_ctx {
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struct userfaultfd_ctx *ctx;
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unsigned long start;
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unsigned long end;
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struct list_head list;
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};
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struct userfaultfd_wait_queue {
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struct uffd_msg msg;
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wait_queue_t wq;
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@ -709,6 +716,64 @@ void userfaultfd_remove(struct vm_area_struct *vma,
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down_read(&mm->mmap_sem);
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}
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static bool has_unmap_ctx(struct userfaultfd_ctx *ctx, struct list_head *unmaps,
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unsigned long start, unsigned long end)
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{
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struct userfaultfd_unmap_ctx *unmap_ctx;
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list_for_each_entry(unmap_ctx, unmaps, list)
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if (unmap_ctx->ctx == ctx && unmap_ctx->start == start &&
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unmap_ctx->end == end)
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return true;
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return false;
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}
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int userfaultfd_unmap_prep(struct vm_area_struct *vma,
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unsigned long start, unsigned long end,
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struct list_head *unmaps)
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{
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for ( ; vma && vma->vm_start < end; vma = vma->vm_next) {
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struct userfaultfd_unmap_ctx *unmap_ctx;
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struct userfaultfd_ctx *ctx = vma->vm_userfaultfd_ctx.ctx;
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if (!ctx || !(ctx->features & UFFD_FEATURE_EVENT_UNMAP) ||
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has_unmap_ctx(ctx, unmaps, start, end))
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continue;
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unmap_ctx = kzalloc(sizeof(*unmap_ctx), GFP_KERNEL);
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if (!unmap_ctx)
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return -ENOMEM;
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userfaultfd_ctx_get(ctx);
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unmap_ctx->ctx = ctx;
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unmap_ctx->start = start;
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unmap_ctx->end = end;
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list_add_tail(&unmap_ctx->list, unmaps);
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}
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return 0;
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}
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void userfaultfd_unmap_complete(struct mm_struct *mm, struct list_head *uf)
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{
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struct userfaultfd_unmap_ctx *ctx, *n;
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struct userfaultfd_wait_queue ewq;
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list_for_each_entry_safe(ctx, n, uf, list) {
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msg_init(&ewq.msg);
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ewq.msg.event = UFFD_EVENT_UNMAP;
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ewq.msg.arg.remove.start = ctx->start;
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ewq.msg.arg.remove.end = ctx->end;
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userfaultfd_event_wait_completion(ctx->ctx, &ewq);
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list_del(&ctx->list);
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kfree(ctx);
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}
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}
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static int userfaultfd_release(struct inode *inode, struct file *file)
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{
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struct userfaultfd_ctx *ctx = file->private_data;
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@ -2090,18 +2090,22 @@ extern int install_special_mapping(struct mm_struct *mm,
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extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
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extern unsigned long mmap_region(struct file *file, unsigned long addr,
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unsigned long len, vm_flags_t vm_flags, unsigned long pgoff);
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unsigned long len, vm_flags_t vm_flags, unsigned long pgoff,
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struct list_head *uf);
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extern unsigned long do_mmap(struct file *file, unsigned long addr,
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unsigned long len, unsigned long prot, unsigned long flags,
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vm_flags_t vm_flags, unsigned long pgoff, unsigned long *populate);
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extern int do_munmap(struct mm_struct *, unsigned long, size_t);
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vm_flags_t vm_flags, unsigned long pgoff, unsigned long *populate,
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struct list_head *uf);
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extern int do_munmap(struct mm_struct *, unsigned long, size_t,
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struct list_head *uf);
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static inline unsigned long
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do_mmap_pgoff(struct file *file, unsigned long addr,
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unsigned long len, unsigned long prot, unsigned long flags,
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unsigned long pgoff, unsigned long *populate)
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unsigned long pgoff, unsigned long *populate,
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struct list_head *uf)
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{
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return do_mmap(file, addr, len, prot, flags, 0, pgoff, populate);
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return do_mmap(file, addr, len, prot, flags, 0, pgoff, populate, uf);
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}
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#ifdef CONFIG_MMU
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@ -66,6 +66,12 @@ extern void userfaultfd_remove(struct vm_area_struct *vma,
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unsigned long start,
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unsigned long end);
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extern int userfaultfd_unmap_prep(struct vm_area_struct *vma,
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unsigned long start, unsigned long end,
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struct list_head *uf);
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extern void userfaultfd_unmap_complete(struct mm_struct *mm,
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struct list_head *uf);
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#else /* CONFIG_USERFAULTFD */
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/* mm helpers */
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@ -118,6 +124,18 @@ static inline void userfaultfd_remove(struct vm_area_struct *vma,
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unsigned long end)
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{
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}
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static inline int userfaultfd_unmap_prep(struct vm_area_struct *vma,
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unsigned long start, unsigned long end,
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struct list_head *uf)
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{
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return 0;
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}
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static inline void userfaultfd_unmap_complete(struct mm_struct *mm,
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struct list_head *uf)
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{
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}
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#endif /* CONFIG_USERFAULTFD */
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#endif /* _LINUX_USERFAULTFD_K_H */
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@ -21,6 +21,7 @@
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#define UFFD_API_FEATURES (UFFD_FEATURE_EVENT_FORK | \
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UFFD_FEATURE_EVENT_REMAP | \
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UFFD_FEATURE_EVENT_REMOVE | \
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UFFD_FEATURE_EVENT_UNMAP | \
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UFFD_FEATURE_MISSING_HUGETLBFS | \
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UFFD_FEATURE_MISSING_SHMEM)
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#define UFFD_API_IOCTLS \
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@ -110,6 +111,7 @@ struct uffd_msg {
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#define UFFD_EVENT_FORK 0x13
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#define UFFD_EVENT_REMAP 0x14
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#define UFFD_EVENT_REMOVE 0x15
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#define UFFD_EVENT_UNMAP 0x16
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/* flags for UFFD_EVENT_PAGEFAULT */
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#define UFFD_PAGEFAULT_FLAG_WRITE (1<<0) /* If this was a write fault */
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@ -158,6 +160,7 @@ struct uffdio_api {
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#define UFFD_FEATURE_EVENT_REMOVE (1<<3)
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#define UFFD_FEATURE_MISSING_HUGETLBFS (1<<4)
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#define UFFD_FEATURE_MISSING_SHMEM (1<<5)
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#define UFFD_FEATURE_EVENT_UNMAP (1<<6)
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__u64 features;
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__u64 ioctls;
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@ -1222,7 +1222,7 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr,
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goto invalid;
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}
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addr = do_mmap_pgoff(file, addr, size, prot, flags, 0, &populate);
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addr = do_mmap_pgoff(file, addr, size, prot, flags, 0, &populate, NULL);
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*raddr = addr;
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err = 0;
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if (IS_ERR_VALUE(addr))
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@ -1329,7 +1329,7 @@ SYSCALL_DEFINE1(shmdt, char __user *, shmaddr)
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*/
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file = vma->vm_file;
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size = i_size_read(file_inode(vma->vm_file));
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do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
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do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start, NULL);
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/*
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* We discovered the size of the shm segment, so
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* break out of here and fall through to the next
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@ -1356,7 +1356,7 @@ SYSCALL_DEFINE1(shmdt, char __user *, shmaddr)
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if ((vma->vm_ops == &shm_vm_ops) &&
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((vma->vm_start - addr)/PAGE_SIZE == vma->vm_pgoff) &&
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(vma->vm_file == file))
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do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
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do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start, NULL);
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vma = next;
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}
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@ -1365,7 +1365,7 @@ SYSCALL_DEFINE1(shmdt, char __user *, shmaddr)
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* given
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*/
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if (vma && vma->vm_start == addr && vma->vm_ops == &shm_vm_ops) {
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do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start);
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do_munmap(mm, vma->vm_start, vma->vm_end - vma->vm_start, NULL);
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retval = 0;
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}
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|
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46
mm/mmap.c
46
mm/mmap.c
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@ -176,7 +176,7 @@ static struct vm_area_struct *remove_vma(struct vm_area_struct *vma)
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return next;
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}
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|
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static int do_brk(unsigned long addr, unsigned long len);
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static int do_brk(unsigned long addr, unsigned long len, struct list_head *uf);
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|
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SYSCALL_DEFINE1(brk, unsigned long, brk)
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{
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@ -185,6 +185,7 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
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struct mm_struct *mm = current->mm;
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unsigned long min_brk;
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bool populate;
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LIST_HEAD(uf);
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|
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if (down_write_killable(&mm->mmap_sem))
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return -EINTR;
|
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|
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@ -222,7 +223,7 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
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|
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/* Always allow shrinking brk. */
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if (brk <= mm->brk) {
|
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if (!do_munmap(mm, newbrk, oldbrk-newbrk))
|
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if (!do_munmap(mm, newbrk, oldbrk-newbrk, &uf))
|
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goto set_brk;
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goto out;
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}
|
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|
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@ -232,13 +233,14 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
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goto out;
|
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|
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/* Ok, looks good - let it rip. */
|
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if (do_brk(oldbrk, newbrk-oldbrk) < 0)
|
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if (do_brk(oldbrk, newbrk-oldbrk, &uf) < 0)
|
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goto out;
|
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|
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set_brk:
|
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mm->brk = brk;
|
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populate = newbrk > oldbrk && (mm->def_flags & VM_LOCKED) != 0;
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up_write(&mm->mmap_sem);
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userfaultfd_unmap_complete(mm, &uf);
|
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if (populate)
|
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mm_populate(oldbrk, newbrk - oldbrk);
|
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return brk;
|
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|
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@ -1304,7 +1306,8 @@ static inline int mlock_future_check(struct mm_struct *mm,
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unsigned long do_mmap(struct file *file, unsigned long addr,
|
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unsigned long len, unsigned long prot,
|
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unsigned long flags, vm_flags_t vm_flags,
|
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unsigned long pgoff, unsigned long *populate)
|
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unsigned long pgoff, unsigned long *populate,
|
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struct list_head *uf)
|
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{
|
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struct mm_struct *mm = current->mm;
|
||||
int pkey = 0;
|
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|
|
@ -1447,7 +1450,7 @@ unsigned long do_mmap(struct file *file, unsigned long addr,
|
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vm_flags |= VM_NORESERVE;
|
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}
|
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|
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addr = mmap_region(file, addr, len, vm_flags, pgoff);
|
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addr = mmap_region(file, addr, len, vm_flags, pgoff, uf);
|
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if (!IS_ERR_VALUE(addr) &&
|
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((vm_flags & VM_LOCKED) ||
|
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(flags & (MAP_POPULATE | MAP_NONBLOCK)) == MAP_POPULATE))
|
||||
|
|
@ -1583,7 +1586,8 @@ static inline int accountable_mapping(struct file *file, vm_flags_t vm_flags)
|
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}
|
||||
|
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unsigned long mmap_region(struct file *file, unsigned long addr,
|
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unsigned long len, vm_flags_t vm_flags, unsigned long pgoff)
|
||||
unsigned long len, vm_flags_t vm_flags, unsigned long pgoff,
|
||||
struct list_head *uf)
|
||||
{
|
||||
struct mm_struct *mm = current->mm;
|
||||
struct vm_area_struct *vma, *prev;
|
||||
|
|
@ -1609,7 +1613,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
|
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/* Clear old maps */
|
||||
while (find_vma_links(mm, addr, addr + len, &prev, &rb_link,
|
||||
&rb_parent)) {
|
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if (do_munmap(mm, addr, len))
|
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if (do_munmap(mm, addr, len, uf))
|
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return -ENOMEM;
|
||||
}
|
||||
|
||||
|
|
@ -2579,7 +2583,8 @@ int split_vma(struct mm_struct *mm, struct vm_area_struct *vma,
|
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* work. This now handles partial unmappings.
|
||||
* Jeremy Fitzhardinge <jeremy@goop.org>
|
||||
*/
|
||||
int do_munmap(struct mm_struct *mm, unsigned long start, size_t len)
|
||||
int do_munmap(struct mm_struct *mm, unsigned long start, size_t len,
|
||||
struct list_head *uf)
|
||||
{
|
||||
unsigned long end;
|
||||
struct vm_area_struct *vma, *prev, *last;
|
||||
|
|
@ -2603,6 +2608,13 @@ int do_munmap(struct mm_struct *mm, unsigned long start, size_t len)
|
|||
if (vma->vm_start >= end)
|
||||
return 0;
|
||||
|
||||
if (uf) {
|
||||
int error = userfaultfd_unmap_prep(vma, start, end, uf);
|
||||
|
||||
if (error)
|
||||
return error;
|
||||
}
|
||||
|
||||
/*
|
||||
* If we need to split any vma, do it now to save pain later.
|
||||
*
|
||||
|
|
@ -2668,12 +2680,14 @@ int vm_munmap(unsigned long start, size_t len)
|
|||
{
|
||||
int ret;
|
||||
struct mm_struct *mm = current->mm;
|
||||
LIST_HEAD(uf);
|
||||
|
||||
if (down_write_killable(&mm->mmap_sem))
|
||||
return -EINTR;
|
||||
|
||||
ret = do_munmap(mm, start, len);
|
||||
ret = do_munmap(mm, start, len, &uf);
|
||||
up_write(&mm->mmap_sem);
|
||||
userfaultfd_unmap_complete(mm, &uf);
|
||||
return ret;
|
||||
}
|
||||
EXPORT_SYMBOL(vm_munmap);
|
||||
|
|
@ -2773,7 +2787,7 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
|
|||
|
||||
file = get_file(vma->vm_file);
|
||||
ret = do_mmap_pgoff(vma->vm_file, start, size,
|
||||
prot, flags, pgoff, &populate);
|
||||
prot, flags, pgoff, &populate, NULL);
|
||||
fput(file);
|
||||
out:
|
||||
up_write(&mm->mmap_sem);
|
||||
|
|
@ -2799,7 +2813,7 @@ static inline void verify_mm_writelocked(struct mm_struct *mm)
|
|||
* anonymous maps. eventually we may be able to do some
|
||||
* brk-specific accounting here.
|
||||
*/
|
||||
static int do_brk_flags(unsigned long addr, unsigned long request, unsigned long flags)
|
||||
static int do_brk_flags(unsigned long addr, unsigned long request, unsigned long flags, struct list_head *uf)
|
||||
{
|
||||
struct mm_struct *mm = current->mm;
|
||||
struct vm_area_struct *vma, *prev;
|
||||
|
|
@ -2838,7 +2852,7 @@ static int do_brk_flags(unsigned long addr, unsigned long request, unsigned long
|
|||
*/
|
||||
while (find_vma_links(mm, addr, addr + len, &prev, &rb_link,
|
||||
&rb_parent)) {
|
||||
if (do_munmap(mm, addr, len))
|
||||
if (do_munmap(mm, addr, len, uf))
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
|
|
@ -2885,9 +2899,9 @@ out:
|
|||
return 0;
|
||||
}
|
||||
|
||||
static int do_brk(unsigned long addr, unsigned long len)
|
||||
static int do_brk(unsigned long addr, unsigned long len, struct list_head *uf)
|
||||
{
|
||||
return do_brk_flags(addr, len, 0);
|
||||
return do_brk_flags(addr, len, 0, uf);
|
||||
}
|
||||
|
||||
int vm_brk_flags(unsigned long addr, unsigned long len, unsigned long flags)
|
||||
|
|
@ -2895,13 +2909,15 @@ int vm_brk_flags(unsigned long addr, unsigned long len, unsigned long flags)
|
|||
struct mm_struct *mm = current->mm;
|
||||
int ret;
|
||||
bool populate;
|
||||
LIST_HEAD(uf);
|
||||
|
||||
if (down_write_killable(&mm->mmap_sem))
|
||||
return -EINTR;
|
||||
|
||||
ret = do_brk_flags(addr, len, flags);
|
||||
ret = do_brk_flags(addr, len, flags, &uf);
|
||||
populate = ((mm->def_flags & VM_LOCKED) != 0);
|
||||
up_write(&mm->mmap_sem);
|
||||
userfaultfd_unmap_complete(mm, &uf);
|
||||
if (populate && !ret)
|
||||
mm_populate(addr, len);
|
||||
return ret;
|
||||
|
|
|
|||
23
mm/mremap.c
23
mm/mremap.c
|
|
@ -252,7 +252,8 @@ unsigned long move_page_tables(struct vm_area_struct *vma,
|
|||
static unsigned long move_vma(struct vm_area_struct *vma,
|
||||
unsigned long old_addr, unsigned long old_len,
|
||||
unsigned long new_len, unsigned long new_addr,
|
||||
bool *locked, struct vm_userfaultfd_ctx *uf)
|
||||
bool *locked, struct vm_userfaultfd_ctx *uf,
|
||||
struct list_head *uf_unmap)
|
||||
{
|
||||
struct mm_struct *mm = vma->vm_mm;
|
||||
struct vm_area_struct *new_vma;
|
||||
|
|
@ -341,7 +342,7 @@ static unsigned long move_vma(struct vm_area_struct *vma,
|
|||
if (unlikely(vma->vm_flags & VM_PFNMAP))
|
||||
untrack_pfn_moved(vma);
|
||||
|
||||
if (do_munmap(mm, old_addr, old_len) < 0) {
|
||||
if (do_munmap(mm, old_addr, old_len, uf_unmap) < 0) {
|
||||
/* OOM: unable to split vma, just get accounts right */
|
||||
vm_unacct_memory(excess >> PAGE_SHIFT);
|
||||
excess = 0;
|
||||
|
|
@ -417,7 +418,8 @@ static struct vm_area_struct *vma_to_resize(unsigned long addr,
|
|||
|
||||
static unsigned long mremap_to(unsigned long addr, unsigned long old_len,
|
||||
unsigned long new_addr, unsigned long new_len, bool *locked,
|
||||
struct vm_userfaultfd_ctx *uf)
|
||||
struct vm_userfaultfd_ctx *uf,
|
||||
struct list_head *uf_unmap)
|
||||
{
|
||||
struct mm_struct *mm = current->mm;
|
||||
struct vm_area_struct *vma;
|
||||
|
|
@ -435,12 +437,12 @@ static unsigned long mremap_to(unsigned long addr, unsigned long old_len,
|
|||
if (addr + old_len > new_addr && new_addr + new_len > addr)
|
||||
goto out;
|
||||
|
||||
ret = do_munmap(mm, new_addr, new_len);
|
||||
ret = do_munmap(mm, new_addr, new_len, NULL);
|
||||
if (ret)
|
||||
goto out;
|
||||
|
||||
if (old_len >= new_len) {
|
||||
ret = do_munmap(mm, addr+new_len, old_len - new_len);
|
||||
ret = do_munmap(mm, addr+new_len, old_len - new_len, uf_unmap);
|
||||
if (ret && old_len != new_len)
|
||||
goto out;
|
||||
old_len = new_len;
|
||||
|
|
@ -462,7 +464,8 @@ static unsigned long mremap_to(unsigned long addr, unsigned long old_len,
|
|||
if (offset_in_page(ret))
|
||||
goto out1;
|
||||
|
||||
ret = move_vma(vma, addr, old_len, new_len, new_addr, locked, uf);
|
||||
ret = move_vma(vma, addr, old_len, new_len, new_addr, locked, uf,
|
||||
uf_unmap);
|
||||
if (!(offset_in_page(ret)))
|
||||
goto out;
|
||||
out1:
|
||||
|
|
@ -502,6 +505,7 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
|
|||
unsigned long charged = 0;
|
||||
bool locked = false;
|
||||
struct vm_userfaultfd_ctx uf = NULL_VM_UFFD_CTX;
|
||||
LIST_HEAD(uf_unmap);
|
||||
|
||||
if (flags & ~(MREMAP_FIXED | MREMAP_MAYMOVE))
|
||||
return ret;
|
||||
|
|
@ -528,7 +532,7 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
|
|||
|
||||
if (flags & MREMAP_FIXED) {
|
||||
ret = mremap_to(addr, old_len, new_addr, new_len,
|
||||
&locked, &uf);
|
||||
&locked, &uf, &uf_unmap);
|
||||
goto out;
|
||||
}
|
||||
|
||||
|
|
@ -538,7 +542,7 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
|
|||
* do_munmap does all the needed commit accounting
|
||||
*/
|
||||
if (old_len >= new_len) {
|
||||
ret = do_munmap(mm, addr+new_len, old_len - new_len);
|
||||
ret = do_munmap(mm, addr+new_len, old_len - new_len, &uf_unmap);
|
||||
if (ret && old_len != new_len)
|
||||
goto out;
|
||||
ret = addr;
|
||||
|
|
@ -598,7 +602,7 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
|
|||
}
|
||||
|
||||
ret = move_vma(vma, addr, old_len, new_len, new_addr,
|
||||
&locked, &uf);
|
||||
&locked, &uf, &uf_unmap);
|
||||
}
|
||||
out:
|
||||
if (offset_in_page(ret)) {
|
||||
|
|
@ -609,5 +613,6 @@ out:
|
|||
if (locked && new_len > old_len)
|
||||
mm_populate(new_addr + old_len, new_len - old_len);
|
||||
mremap_userfaultfd_complete(&uf, addr, new_addr, old_len);
|
||||
userfaultfd_unmap_complete(mm, &uf_unmap);
|
||||
return ret;
|
||||
}
|
||||
|
|
|
|||
|
|
@ -1205,7 +1205,8 @@ unsigned long do_mmap(struct file *file,
|
|||
unsigned long flags,
|
||||
vm_flags_t vm_flags,
|
||||
unsigned long pgoff,
|
||||
unsigned long *populate)
|
||||
unsigned long *populate,
|
||||
struct list_head *uf)
|
||||
{
|
||||
struct vm_area_struct *vma;
|
||||
struct vm_region *region;
|
||||
|
|
@ -1577,7 +1578,7 @@ static int shrink_vma(struct mm_struct *mm,
|
|||
* - under NOMMU conditions the chunk to be unmapped must be backed by a single
|
||||
* VMA, though it need not cover the whole VMA
|
||||
*/
|
||||
int do_munmap(struct mm_struct *mm, unsigned long start, size_t len)
|
||||
int do_munmap(struct mm_struct *mm, unsigned long start, size_t len, struct list_head *uf)
|
||||
{
|
||||
struct vm_area_struct *vma;
|
||||
unsigned long end;
|
||||
|
|
@ -1643,7 +1644,7 @@ int vm_munmap(unsigned long addr, size_t len)
|
|||
int ret;
|
||||
|
||||
down_write(&mm->mmap_sem);
|
||||
ret = do_munmap(mm, addr, len);
|
||||
ret = do_munmap(mm, addr, len, NULL);
|
||||
up_write(&mm->mmap_sem);
|
||||
return ret;
|
||||
}
|
||||
|
|
|
|||
|
|
@ -11,6 +11,7 @@
|
|||
#include <linux/mman.h>
|
||||
#include <linux/hugetlb.h>
|
||||
#include <linux/vmalloc.h>
|
||||
#include <linux/userfaultfd_k.h>
|
||||
|
||||
#include <asm/sections.h>
|
||||
#include <linux/uaccess.h>
|
||||
|
|
@ -297,14 +298,16 @@ unsigned long vm_mmap_pgoff(struct file *file, unsigned long addr,
|
|||
unsigned long ret;
|
||||
struct mm_struct *mm = current->mm;
|
||||
unsigned long populate;
|
||||
LIST_HEAD(uf);
|
||||
|
||||
ret = security_mmap_file(file, prot, flag);
|
||||
if (!ret) {
|
||||
if (down_write_killable(&mm->mmap_sem))
|
||||
return -EINTR;
|
||||
ret = do_mmap_pgoff(file, addr, len, prot, flag, pgoff,
|
||||
&populate);
|
||||
&populate, &uf);
|
||||
up_write(&mm->mmap_sem);
|
||||
userfaultfd_unmap_complete(mm, &uf);
|
||||
if (populate)
|
||||
mm_populate(ret, populate);
|
||||
}
|
||||
|
|
|
|||
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