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From: Liam Howlett <liam.howlett@oracle.com>
To: "maple-tree@lists.infradead.org" <maple-tree@lists.infradead.org>,
	"linux-mm@kvack.org" <linux-mm@kvack.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>
Cc: Song Liu <songliubraving@fb.com>,
	Davidlohr Bueso <dave@stgolabs.net>,
	"Paul E . McKenney" <paulmck@kernel.org>,
	Matthew Wilcox <willy@infradead.org>,
	Laurent Dufour <ldufour@linux.ibm.com>,
	David Rientjes <rientjes@google.com>,
	Axel Rasmussen <axelrasmussen@google.com>,
	Suren Baghdasaryan <surenb@google.com>,
	Vlastimil Babka <vbabka@suse.cz>, Rik van Riel <riel@surriel.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Michel Lespinasse <walken.cr@gmail.com>,
	Liam Howlett <liam.howlett@oracle.com>
Subject: [PATCH 67/94] fs/userfaultfd: Stop using vma linked list.
Date: Wed, 28 Apr 2021 15:36:21 +0000	[thread overview]
Message-ID: <20210428153542.2814175-68-Liam.Howlett@Oracle.com> (raw)
In-Reply-To: <20210428153542.2814175-1-Liam.Howlett@Oracle.com>

Don't use the mm_struct linked list or the vma->vm_next in prep for removal

Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
---
 fs/userfaultfd.c | 43 ++++++++++++++++++++++++++++++++++++-------
 1 file changed, 36 insertions(+), 7 deletions(-)

diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index 14f92285d04f..1fd0f5b5c934 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -605,14 +605,18 @@ static void userfaultfd_event_wait_completion(struct userfaultfd_ctx *ctx,
 	if (release_new_ctx) {
 		struct vm_area_struct *vma;
 		struct mm_struct *mm = release_new_ctx->mm;
+		MA_STATE(mas, &mm->mm_mt, 0, 0);
 
 		/* the various vma->vm_userfaultfd_ctx still points to it */
 		mmap_write_lock(mm);
-		for (vma = mm->mmap; vma; vma = vma->vm_next)
+		mas_lock(&mas);
+		mas_for_each(&mas, vma, ULONG_MAX) {
 			if (vma->vm_userfaultfd_ctx.ctx == release_new_ctx) {
 				vma->vm_userfaultfd_ctx = NULL_VM_UFFD_CTX;
 				vma->vm_flags &= ~__VM_UFFD_FLAGS;
 			}
+		}
+		mas_unlock(&mas);
 		mmap_write_unlock(mm);
 
 		userfaultfd_ctx_put(release_new_ctx);
@@ -797,7 +801,10 @@ int userfaultfd_unmap_prep(struct vm_area_struct *vma,
 			   unsigned long start, unsigned long end,
 			   struct list_head *unmaps)
 {
-	for ( ; vma && vma->vm_start < end; vma = vma->vm_next) {
+	MA_STATE(mas, &vma->vm_mm->mm_mt, vma->vm_start, vma->vm_start);
+
+	rcu_read_lock();
+	mas_for_each(&mas, vma, end) {
 		struct userfaultfd_unmap_ctx *unmap_ctx;
 		struct userfaultfd_ctx *ctx = vma->vm_userfaultfd_ctx.ctx;
 
@@ -816,6 +823,7 @@ int userfaultfd_unmap_prep(struct vm_area_struct *vma,
 		unmap_ctx->end = end;
 		list_add_tail(&unmap_ctx->list, unmaps);
 	}
+	rcu_read_unlock();
 
 	return 0;
 }
@@ -847,6 +855,7 @@ static int userfaultfd_release(struct inode *inode, struct file *file)
 	/* len == 0 means wake all */
 	struct userfaultfd_wake_range range = { .len = 0, };
 	unsigned long new_flags;
+	MA_STATE(mas, &mm->mm_mt, 0, 0);
 
 	WRITE_ONCE(ctx->released, true);
 
@@ -862,9 +871,14 @@ static int userfaultfd_release(struct inode *inode, struct file *file)
 	 * taking the mmap_lock for writing.
 	 */
 	mmap_write_lock(mm);
+	mas_lock(&mas);
 	prev = NULL;
-	for (vma = mm->mmap; vma; vma = vma->vm_next) {
+	mas_for_each(&mas, vma, ULONG_MAX) {
+		mas_unlock(&mas);
+		mas_pause(&mas);
 		cond_resched();
+		mas_lock(&mas);
+
 		BUG_ON(!!vma->vm_userfaultfd_ctx.ctx ^
 		       !!(vma->vm_flags & __VM_UFFD_FLAGS));
 		if (vma->vm_userfaultfd_ctx.ctx != ctx) {
@@ -884,6 +898,7 @@ static int userfaultfd_release(struct inode *inode, struct file *file)
 		vma->vm_flags = new_flags;
 		vma->vm_userfaultfd_ctx = NULL_VM_UFFD_CTX;
 	}
+	mas_unlock(&mas);
 	mmap_write_unlock(mm);
 	mmput(mm);
 wakeup:
@@ -1288,6 +1303,7 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx,
 	bool found;
 	bool basic_ioctls;
 	unsigned long start, end, vma_end;
+	MA_STATE(mas, &mm->mm_mt, 0, 0);
 
 	user_uffdio_register = (struct uffdio_register __user *) arg;
 
@@ -1326,6 +1342,7 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx,
 		goto out;
 
 	mmap_write_lock(mm);
+	rcu_read_lock();
 	vma = find_vma_prev(mm, start, &prev);
 	if (!vma)
 		goto out_unlock;
@@ -1351,8 +1368,12 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx,
 	 */
 	found = false;
 	basic_ioctls = false;
-	for (cur = vma; cur && cur->vm_start < end; cur = cur->vm_next) {
+	mas_set(&mas, vma->vm_start);
+	mas_for_each(&mas, cur, end) {
+		rcu_read_unlock();
+		mas_pause(&mas);
 		cond_resched();
+		rcu_read_lock();
 
 		BUG_ON(!!cur->vm_userfaultfd_ctx.ctx ^
 		       !!(cur->vm_flags & __VM_UFFD_FLAGS));
@@ -1469,9 +1490,10 @@ static int userfaultfd_register(struct userfaultfd_ctx *ctx,
 	skip:
 		prev = vma;
 		start = vma->vm_end;
-		vma = vma->vm_next;
+		vma = vma_next(mm, vma);
 	} while (vma && vma->vm_start < end);
 out_unlock:
+	rcu_read_unlock();
 	mmap_write_unlock(mm);
 	mmput(mm);
 	if (!ret) {
@@ -1514,6 +1536,7 @@ static int userfaultfd_unregister(struct userfaultfd_ctx *ctx,
 	bool found;
 	unsigned long start, end, vma_end;
 	const void __user *buf = (void __user *)arg;
+	MA_STATE(mas, &mm->mm_mt, 0, 0);
 
 	ret = -EFAULT;
 	if (copy_from_user(&uffdio_unregister, buf, sizeof(uffdio_unregister)))
@@ -1557,8 +1580,13 @@ static int userfaultfd_unregister(struct userfaultfd_ctx *ctx,
 	 */
 	found = false;
 	ret = -EINVAL;
-	for (cur = vma; cur && cur->vm_start < end; cur = cur->vm_next) {
+	rcu_read_lock();
+	mas_set(&mas, vma->vm_start);
+	mas_for_each(&mas, cur, end) {
+		rcu_read_unlock();
+		mas_pause(&mas);
 		cond_resched();
+		rcu_read_lock();
 
 		BUG_ON(!!cur->vm_userfaultfd_ctx.ctx ^
 		       !!(cur->vm_flags & __VM_UFFD_FLAGS));
@@ -1575,6 +1603,7 @@ static int userfaultfd_unregister(struct userfaultfd_ctx *ctx,
 
 		found = true;
 	}
+	rcu_read_unlock();
 	BUG_ON(!found);
 
 	if (vma->vm_start < start)
@@ -1643,7 +1672,7 @@ static int userfaultfd_unregister(struct userfaultfd_ctx *ctx,
 	skip:
 		prev = vma;
 		start = vma->vm_end;
-		vma = vma->vm_next;
+		vma = vma_next(mm, vma);
 	} while (vma && vma->vm_start < end);
 out_unlock:
 	mmap_write_unlock(mm);
-- 
2.30.2

  parent reply	other threads:[~2021-04-28 15:40 UTC|newest]

Thread overview: 136+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-28 15:35 [PATCH 00/94] Introducing the Maple Tree Liam Howlett
2021-04-28 15:35 ` [PATCH 01/94] mm: Add vma_lookup() Liam Howlett
2021-05-01  5:04   ` Michel Lespinasse
2021-05-03 16:08     ` Liam Howlett
2021-04-28 15:35 ` [PATCH 02/94] drm/i915/selftests: Use vma_lookup() in __igt_mmap() Liam Howlett
2021-04-28 15:35 ` [PATCH 03/94] arch/arc/kernel/troubleshoot: use vma_lookup() instead of find_vma_intersection() Liam Howlett
2021-04-28 15:35 ` [PATCH 04/94] arch/arm64/kvm: Use " Liam Howlett
2021-04-28 15:35 ` [PATCH 05/94] arch/powerpc/kvm/book3s_hv_uvmem: " Liam Howlett
2021-04-28 15:35 ` [PATCH 06/94] arch/powerpc/kvm/book3s: Use vma_lookup() in kvmppc_hv_setup_htab_rma() Liam Howlett
2021-04-28 15:35 ` [PATCH 08/94] x86/sgx: Use vma_lookup() in sgx_encl_find() Liam Howlett
2021-04-28 15:35 ` [PATCH 07/94] arch/mips/kernel/traps: Use vma_lookup() instead of find_vma_intersection() Liam Howlett
2021-04-28 15:35 ` [PATCH 09/94] virt/kvm: " Liam Howlett
2021-04-28 15:35 ` [PATCH 10/94] vfio: " Liam Howlett
2021-04-28 15:35 ` [PATCH 12/94] drm/amdgpu: Use vma_lookup() in amdgpu_ttm_tt_get_user_pages() Liam Howlett
2021-04-28 15:35 ` [PATCH 11/94] net/ipv5/tcp: Use vma_lookup() in tcp_zerocopy_receive() Liam Howlett
2021-04-28 15:35 ` [PATCH 15/94] kernel/events/uprobes: Use vma_lookup() in find_active_uprobe() Liam Howlett
2021-04-28 15:35 ` [PATCH 14/94] misc/sgi-gru/grufault: Use vma_lookup() in gru_find_vma() Liam Howlett
2021-04-28 15:35 ` [PATCH 13/94] media: videobuf2: Use vma_lookup() in get_vaddr_frames() Liam Howlett
2021-04-28 15:35 ` [PATCH 16/94] lib/test_hmm: Use vma_lookup() in dmirror_migrate() Liam Howlett
2021-04-28 15:35 ` [PATCH 18/94] mm/migrate: Use vma_lookup() in do_pages_stat_array() Liam Howlett
2021-04-28 15:35 ` [PATCH 17/94] mm/ksm: Use vma_lookup() in find_mergeable_vma() Liam Howlett
2021-04-28 15:35 ` [PATCH 19/94] mm/mremap: Use vma_lookup() in vma_to_resize() Liam Howlett
2021-04-28 15:35 ` [PATCH 20/94] mm/memory.c: Use vma_lookup() instead of find_vma_intersection() Liam Howlett
2021-04-28 15:35 ` [PATCH 21/94] radix tree test suite: Enhancements for Maple Tree Liam Howlett
2021-05-28 17:30   ` Suren Baghdasaryan
2021-05-28 18:54     ` Liam Howlett
2021-04-28 15:35 ` [PATCH 23/94] radix tree test suite: Add support for kmem_cache_free_bulk Liam Howlett
2021-05-28 17:55   ` Suren Baghdasaryan
2021-05-28 19:07     ` Liam Howlett
2021-04-28 15:35 ` [PATCH 22/94] radix tree test suite: Add support for fallthrough attribute Liam Howlett
2021-04-28 15:35 ` [PATCH 24/94] radix tree test suite: Add keme_cache_alloc_bulk() support Liam Howlett
2021-05-28 18:17   ` Suren Baghdasaryan
2021-05-28 19:28     ` Liam Howlett
2021-04-28 15:35 ` [PATCH 25/94] radix tree test suite: Add __must_be_array() support Liam Howlett
2021-04-28 15:36 ` [PATCH 26/94] Maple Tree: Add new data structure Liam Howlett
2021-05-14 10:40   ` Peter Zijlstra
2021-05-14 20:36     ` Liam Howlett
2021-05-14 10:56   ` Peter Zijlstra
2021-05-14 20:45     ` Liam Howlett
2021-05-14 11:13   ` Peter Zijlstra
2021-05-14 11:27     ` Peter Zijlstra
2021-05-14 21:23       ` Liam Howlett
2021-05-14 11:20   ` Peter Zijlstra
2021-05-14 20:46     ` Liam Howlett
2021-05-14 11:54   ` Peter Zijlstra
2021-05-14 21:25     ` Liam Howlett
2021-05-14 12:17   ` Peter Zijlstra
2021-05-14 12:43     ` Matthew Wilcox
2021-05-14 21:29     ` Liam Howlett
2021-05-14 13:42   ` Peter Zijlstra
2021-05-14 21:42     ` Liam Howlett
2021-05-14 15:32   ` Peter Zijlstra
2021-05-14 15:34     ` Peter Zijlstra
2021-05-14 21:57       ` Liam Howlett
2021-05-14 21:43     ` Liam Howlett
2021-05-14 15:40   ` Peter Zijlstra
2021-05-15  0:02     ` Liam Howlett
2021-04-28 15:36 ` [PATCH 28/94] mm/mmap: Introduce unlock_range() for code cleanup Liam Howlett
2021-04-28 15:36 ` [PATCH 27/94] mm: Start tracking VMAs with maple tree Liam Howlett
2021-04-28 15:36 ` [PATCH 30/94] mm/mmap: Change find_vma_prev() to use " Liam Howlett
2021-04-28 15:36 ` [PATCH 29/94] mm/mmap: Change find_vma() to use the " Liam Howlett
2021-04-28 15:36 ` [PATCH 32/94] kernel/fork: Convert dup_mmap to use " Liam Howlett
2021-05-29  0:42   ` Suren Baghdasaryan
2021-05-31 13:39     ` Liam Howlett
2021-04-28 15:36 ` [PATCH 31/94] mm/mmap: Change unmapped_area and unmapped_area_topdown " Liam Howlett
2021-04-28 15:36 ` [PATCH 33/94] mm: Remove rb tree Liam Howlett
2021-05-29  1:26   ` Suren Baghdasaryan
2021-05-31 13:42     ` Liam Howlett
2021-04-28 15:36 ` [PATCH 35/94] xen/privcmd: Optimized privcmd_ioctl_mmap() by using vma_lookup() Liam Howlett
2021-04-28 15:36 ` [PATCH 34/94] arch/m68k/kernel/sys_m68k: Use vma_lookup() in sys_cacheflush() Liam Howlett
2021-04-28 15:36 ` [PATCH 37/94] mm/khugepaged: Optimize collapse_pte_mapped_thp() by using vma_lookup() Liam Howlett
2021-04-28 15:36 ` [PATCH 36/94] mm: Optimize find_exact_vma() to use vma_lookup() Liam Howlett
2021-04-28 15:36 ` [PATCH 38/94] mm/gup: Add mm_populate_vma() for use when the vma is known Liam Howlett
2021-05-01  5:13   ` Michel Lespinasse
2021-05-03 15:53     ` Liam Howlett
2021-05-03 16:00       ` Matthew Wilcox
2021-05-03 23:01         ` Liam Howlett
2021-04-28 15:36 ` [PATCH 39/94] mm/mmap: Change do_brk_flags() to expand existing VMA and add do_brk_munmap() Liam Howlett
2021-04-28 15:36 ` [PATCH 40/94] mm/mmap: Change vm_brk_flags() to use mm_populate_vma() Liam Howlett
2021-04-28 15:36 ` [PATCH 41/94] mm: Change find_vma_intersection() to maple tree and make find_vma() to inline Liam Howlett
2021-04-28 15:36 ` [PATCH 44/94] mm: Remove vmacache Liam Howlett
2021-04-28 15:36 ` [PATCH 43/94] mm/mmap: Drop munmap_vma_range() Liam Howlett
2021-04-28 15:36 ` [PATCH 42/94] mm/mmap: Change mmap_region() to use maple tree state Liam Howlett
2021-04-28 15:36 ` [PATCH 45/94] mm/mmap: Change __do_munmap() to avoid unnecessary lookups Liam Howlett
2021-04-28 15:36 ` [PATCH 46/94] mm/mmap: Move mmap_region() below do_munmap() Liam Howlett
2021-04-28 15:36 ` [PATCH 47/94] mm/mmap: Add do_mas_munmap() and wraper for __do_munmap() Liam Howlett
2021-04-28 15:36 ` [PATCH 48/94] mmap: Use find_vma_intersection in do_mmap() for overlap Liam Howlett
2021-04-28 15:36 ` [PATCH 49/94] mmap: Remove __do_munmap() in favour of do_mas_munmap() Liam Howlett
2021-04-28 15:36 ` [PATCH 50/94] mm/mmap: Change do_brk_munmap() to use do_mas_align_munmap() Liam Howlett
2021-04-28 15:36 ` [PATCH 51/94] mmap: make remove_vma_list() inline Liam Howlett
2021-04-28 15:36 ` [PATCH 52/94] mm: Introduce vma_next() and vma_prev() Liam Howlett
2021-04-28 15:36 ` [PATCH 53/94] arch/arm64: Remove mmap linked list from vdso Liam Howlett
2021-04-28 15:36 ` [PATCH 54/94] arch/parisc: Remove mmap linked list from kernel/cache Liam Howlett
2021-04-28 15:36 ` [PATCH 55/94] arch/powerpc: Remove mmap linked list from mm/book3s32/tlb Liam Howlett
2021-04-28 15:36 ` [PATCH 56/94] arch/powerpc: Remove mmap linked list from mm/book3s64/subpage_prot Liam Howlett
2021-04-28 15:36 ` [PATCH 57/94] arch/s390: Use maple tree iterators instead of linked list Liam Howlett
2021-04-28 15:36 ` [PATCH 58/94] arch/x86: Use maple tree iterators for vdso/vma Liam Howlett
2021-04-28 15:36 ` [PATCH 59/94] arch/xtensa: Use maple tree iterators for unmapped area Liam Howlett
2021-04-28 15:36 ` [PATCH 60/94] drivers/misc/cxl: Use maple tree iterators for cxl_prefault_vma() Liam Howlett
2021-04-28 15:36 ` [PATCH 61/94] drivers/tee/optee: Use maple tree iterators for __check_mem_type() Liam Howlett
2021-04-28 15:36 ` [PATCH 63/94] fs/coredump: Use maple tree iterators in place of linked list Liam Howlett
2021-04-28 15:36 ` [PATCH 62/94] fs/binfmt_elf: Use maple tree iterators for fill_files_note() Liam Howlett
2021-04-28 15:36 ` [PATCH 64/94] fs/exec: Use vma_next() instead of linked list Liam Howlett
2021-04-28 15:36 ` [PATCH 65/94] fs/proc/base: Use maple tree iterators in place " Liam Howlett
2021-04-28 15:36 ` [PATCH 66/94] fs/proc/task_mmu: Stop using linked list and highest_vm_end Liam Howlett
2021-04-28 15:36 ` Liam Howlett [this message]
2021-04-28 15:36 ` [PATCH 68/94] ipc/shm: Stop using the vma linked list Liam Howlett
2021-04-28 15:36 ` [PATCH 69/94] kernel/acct: Use maple tree iterators instead of " Liam Howlett
2021-04-28 15:36 ` [PATCH 70/94] kernel/events/core: " Liam Howlett
2021-04-28 15:36 ` [PATCH 71/94] kernel/events/uprobes: " Liam Howlett
2021-04-28 15:36 ` [PATCH 73/94] kernel/sys: " Liam Howlett
2021-04-28 15:36 ` [PATCH 72/94] kernel/sched/fair: " Liam Howlett
2021-04-28 15:36 ` [PATCH 75/94] mm/huge_memory: Use vma_next() instead of vma " Liam Howlett
2021-04-28 15:36 ` [PATCH 76/94] mm/khugepaged: Use maple tree iterators " Liam Howlett
2021-04-28 15:36 ` [PATCH 74/94] mm/gup: Use maple tree navigation instead of " Liam Howlett
2021-04-28 15:36 ` [PATCH 77/94] mm/ksm: Use maple tree iterators instead of vma " Liam Howlett
2021-04-28 15:36 ` [PATCH 78/94] mm/madvise: Use vma_next " Liam Howlett
2021-04-28 15:36 ` [PATCH 79/94] mm/memcontrol: Stop using mm->highest_vm_end Liam Howlett
2021-04-28 15:36 ` [PATCH 81/94] mm/mlock: Use maple tree iterators instead of vma linked list Liam Howlett
2021-04-28 15:36 ` [PATCH 80/94] mm/mempolicy: " Liam Howlett
2021-04-28 15:36 ` [PATCH 82/94] mm/mprotect: Use maple tree navigation " Liam Howlett
2021-04-28 15:36 ` [PATCH 84/94] mm/msync: Use vma_next() " Liam Howlett
2021-04-28 15:36 ` [PATCH 83/94] mm/mremap: " Liam Howlett
2021-04-28 15:36 ` [PATCH 86/94] mm/pagewalk: " Liam Howlett
2021-04-28 15:36 ` [PATCH 85/94] mm/oom_kill: Use maple tree iterators " Liam Howlett
2021-04-28 15:36 ` [PATCH 87/94] mm/swapfile: Use maple tree iterator " Liam Howlett
2021-04-28 15:36 ` [PATCH 88/94] mm/util: Remove __vma_link_list() and __vma_unlink_list() Liam Howlett
2021-04-28 15:36 ` [PATCH 89/94] arch/um/kernel/tlb: Stop using linked list Liam Howlett
2021-04-28 15:36 ` [PATCH 90/94] bpf: Remove VMA " Liam Howlett
2021-04-28 15:36 ` [PATCH 91/94] mm: Remove vma " Liam Howlett
2021-04-28 15:36 ` [PATCH 92/94] mm: Return a bool from anon_vma_interval_tree_verify() Liam Howlett
2021-04-28 15:36 ` [PATCH 94/94] mm: Move mas locking outside of munmap() path Liam Howlett
2021-05-01  6:13   ` Michel Lespinasse
2021-05-03 16:05     ` Liam Howlett
2021-04-28 15:36 ` [PATCH 93/94] mm/mmap: Add mas_split_vma() and use it for munmap() Liam Howlett
     [not found] ` <20210504042930.10436-1-hdanton@sina.com>
2021-05-04 14:05   ` [PATCH 76/94] mm/khugepaged: Use maple tree iterators instead of vma Liam Howlett

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