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Berrange" , Alex Williamson , Alistair Popple , linuxppc-dev@lists.ozlabs.org, linux-fpga@vger.kernel.org, linux-rdma@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, netdev@vger.kernel.org, io-uring@vger.kernel.org, bpf@vger.kernel.org, rds-devel@oss.oracle.com, linux-kselftest@vger.kernel.org Subject: [PATCH 01/19] mm: Introduce vm_account Date: Mon, 6 Feb 2023 18:47:38 +1100 Message-Id: X-Mailer: git-send-email 2.39.0 In-Reply-To: References: X-ClientProxiedBy: SY6PR01CA0010.ausprd01.prod.outlook.com (2603:10c6:10:e8::15) To BYAPR12MB3176.namprd12.prod.outlook.com (2603:10b6:a03:134::26) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BYAPR12MB3176:EE_|CY8PR12MB7097:EE_ X-MS-Office365-Filtering-Correlation-Id: f1f32d26-9f86-4df0-cce9-08db081684ae X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BYAPR12MB3176.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230025)(4636009)(366004)(39860400002)(396003)(136003)(346002)(376002)(451199018)(38100700002)(36756003)(6506007)(6666004)(6512007)(26005)(186003)(478600001)(86362001)(6486002)(8676002)(66476007)(83380400001)(66946007)(2616005)(66556008)(4326008)(316002)(54906003)(7416002)(2906002)(8936002)(5660300002)(41300700001);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: 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 X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: f1f32d26-9f86-4df0-cce9-08db081684ae X-MS-Exchange-CrossTenant-AuthSource: BYAPR12MB3176.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Feb 2023 07:48:21.2970 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: VKLsBrolhjVwe4eRftYA1HkxxQ/SlJh07YGyjddLzMudWGCcOJdVx+UWim/wuIqJ+Bp6tmOMG+wJxI7NtMvsPg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY8PR12MB7097 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org Kernel drivers that pin pages should account these pages against either user->locked_vm and/or mm->pinned_vm and fail the pinning if RLIMIT_MEMLOCK is exceeded and CAP_IPC_LOCK isn't held. Currently drivers open-code this accounting and use various methods to update the atomic variables and check against the limits leading to various bugs and inconsistencies. To fix this introduce a standard interface for charging pinned and locked memory. As this involves taking references on kernel objects such as mm_struct or user_struct we introduce a new vm_account struct to hold these references. Several helper functions are then introduced to grab references and check limits. As the way these limits are charged and enforced is visible to userspace we need to be careful not to break existing applications by charging to different counters. As a result the vm_account functions support accounting to different counters as required. A future change will extend this to also account against a cgroup for pinned pages. Signed-off-by: Alistair Popple Cc: linux-kernel@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-fpga@vger.kernel.org Cc: linux-rdma@vger.kernel.org Cc: virtualization@lists.linux-foundation.org Cc: kvm@vger.kernel.org Cc: netdev@vger.kernel.org Cc: cgroups@vger.kernel.org Cc: io-uring@vger.kernel.org Cc: linux-mm@kvack.org Cc: bpf@vger.kernel.org Cc: rds-devel@oss.oracle.com Cc: linux-kselftest@vger.kernel.org --- include/linux/vm_account.h | 56 +++++++++++++++++- mm/util.c | 127 ++++++++++++++++++++++++++++++++++++++- 2 files changed, 183 insertions(+) create mode 100644 include/linux/vm_account.h diff --git a/include/linux/vm_account.h b/include/linux/vm_account.h new file mode 100644 index 0000000..b4b2e90 --- /dev/null +++ b/include/linux/vm_account.h @@ -0,0 +1,56 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_VM_ACCOUNT_H +#define _LINUX_VM_ACCOUNT_H + +/** + * enum vm_account_flags - Determine how pinned/locked memory is accounted. + * @VM_ACCOUNT_TASK: Account pinned memory to mm->pinned_vm. + * @VM_ACCOUNT_BYPASS: Don't enforce rlimit on any charges. + * @VM_ACCOUNT_USER: Account locked memory to user->locked_vm. + * + * Determines which statistic pinned/locked memory is accounted + * against. All limits will be enforced against RLIMIT_MEMLOCK and the + * pins cgroup if CONFIG_CGROUP_PINS is enabled. + * + * New drivers should use VM_ACCOUNT_USER. VM_ACCOUNT_TASK is used by + * pre-existing drivers to maintain existing accounting against + * mm->pinned_mm rather than user->locked_mm. + * + * VM_ACCOUNT_BYPASS may also be specified to bypass rlimit + * checks. Typically this is used to cache CAP_IPC_LOCK from when a + * driver is first initialised. Note that this does not bypass cgroup + * limit checks. + */ +enum vm_account_flags { + VM_ACCOUNT_USER = 0, + VM_ACCOUNT_BYPASS = 1, + VM_ACCOUNT_TASK = 1, +}; + +struct vm_account { + struct task_struct *task; + struct mm_struct *mm; + struct user_struct *user; + enum vm_account_flags flags; +}; + +void vm_account_init(struct vm_account *vm_account, struct task_struct *task, + struct user_struct *user, enum vm_account_flags flags); + +/** + * vm_account_init_current - Initialise a new struct vm_account. + * @vm_account: pointer to uninitialised vm_account. + * + * Helper to initialise a vm_account for the common case of charging + * with VM_ACCOUNT_TASK against current. + */ +static inline void vm_account_init_current(struct vm_account *vm_account) +{ + vm_account_init(vm_account, current, NULL, VM_ACCOUNT_TASK); +} + +void vm_account_release(struct vm_account *vm_account); +int vm_account_pinned(struct vm_account *vm_account, unsigned long npages); +void vm_unaccount_pinned(struct vm_account *vm_account, unsigned long npages); + +#endif /* _LINUX_VM_ACCOUNT_H */ diff --git a/mm/util.c b/mm/util.c index b56c92f..d8c19f8 100644 --- a/mm/util.c +++ b/mm/util.c @@ -23,6 +23,7 @@ #include #include #include +#include #include @@ -431,6 +432,132 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack) #endif /** + * vm_account_init - Initialise a new struct vm_account. + * @vm_account: pointer to uninitialised vm_account. + * @task: task to charge against. + * @user: user to charge against. Must be non-NULL for VM_ACCOUNT_USER. + * @flags: flags to use when charging to vm_account. + * + * Initialise a new uninitialised struct vm_account. Takes references + * on the task/mm/user/cgroup as required although callers must ensure + * any references passed in remain valid for the duration of this + * call. + */ +void vm_account_init(struct vm_account *vm_account, struct task_struct *task, + struct user_struct *user, enum vm_account_flags flags) +{ + vm_account->task = get_task_struct(task); + + if (flags & VM_ACCOUNT_USER) + vm_account->user = get_uid(user); + + mmgrab(task->mm); + vm_account->mm = task->mm; + vm_account->flags = flags; +} +EXPORT_SYMBOL_GPL(vm_account_init); + +/** + * vm_account_release - Initialise a new struct vm_account. + * @vm_account: pointer to initialised vm_account. + * + * Drop any object references obtained by vm_account_init(). The + * vm_account must not be used after calling this unless reinitialised + * with vm_account_init(). + */ +void vm_account_release(struct vm_account *vm_account) +{ + put_task_struct(vm_account->task); + if (vm_account->flags & VM_ACCOUNT_USER) + free_uid(vm_account->user); + + mmdrop(vm_account->mm); +} +EXPORT_SYMBOL_GPL(vm_account_release); + +/* + * Charge pages with an atomic compare and swap. Returns -ENOMEM on + * failure, 1 on success and 0 for retry. + */ +static int vm_account_cmpxchg(struct vm_account *vm_account, + unsigned long npages, unsigned long lock_limit) +{ + u64 cur_pages, new_pages; + + if (vm_account->flags & VM_ACCOUNT_USER) + cur_pages = atomic_long_read(&vm_account->user->locked_vm); + else + cur_pages = atomic64_read(&vm_account->mm->pinned_vm); + + new_pages = cur_pages + npages; + if (lock_limit != RLIM_INFINITY && new_pages > lock_limit) + return -ENOMEM; + + if (vm_account->flags & VM_ACCOUNT_USER) { + return atomic_long_cmpxchg(&vm_account->user->locked_vm, + cur_pages, new_pages) == cur_pages; + } else { + return atomic64_cmpxchg(&vm_account->mm->pinned_vm, + cur_pages, new_pages) == cur_pages; + } +} + +/** + * vm_account_pinned - Charge pinned or locked memory to the vm_account. + * @vm_account: pointer to an initialised vm_account. + * @npages: number of pages to charge. + * + * Return: 0 on success, -ENOMEM if a limit would be exceeded. + * + * Note: All pages must be explicitly uncharged with + * vm_unaccount_pinned() prior to releasing the vm_account with + * vm_account_release(). + */ +int vm_account_pinned(struct vm_account *vm_account, unsigned long npages) +{ + unsigned long lock_limit = RLIM_INFINITY; + int ret; + + if (!(vm_account->flags & VM_ACCOUNT_BYPASS) && !capable(CAP_IPC_LOCK)) + lock_limit = task_rlimit(vm_account->task, + RLIMIT_MEMLOCK) >> PAGE_SHIFT; + + while (true) { + ret = vm_account_cmpxchg(vm_account, npages, lock_limit); + if (ret > 0) + break; + else if (ret < 0) + return ret; + } + + /* + * Always add pinned pages to mm->pinned_vm even when we're + * not enforcing the limit against that. + */ + if (vm_account->flags & VM_ACCOUNT_USER) + atomic64_add(npages, &vm_account->mm->pinned_vm); + + return 0; +} +EXPORT_SYMBOL_GPL(vm_account_pinned); + +/** + * vm_unaccount_pinned - Uncharge pinned or locked memory to the vm_account. + * @vm_account: pointer to an initialised vm_account. + * @npages: number of pages to uncharge. + */ +void vm_unaccount_pinned(struct vm_account *vm_account, unsigned long npages) +{ + if (vm_account->flags & VM_ACCOUNT_USER) { + atomic_long_sub(npages, &vm_account->user->locked_vm); + atomic64_sub(npages, &vm_account->mm->pinned_vm); + } else { + atomic64_sub(npages, &vm_account->mm->pinned_vm); + } +} +EXPORT_SYMBOL_GPL(vm_unaccount_pinned); + +/** * __account_locked_vm - account locked pages to an mm's locked_vm * @mm: mm to account against * @pages: number of pages to account From patchwork Mon Feb 6 07:47:46 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alistair Popple X-Patchwork-Id: 13129458 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B9C5FC61DA4 for ; Mon, 6 Feb 2023 07:50:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229883AbjBFHuz (ORCPT ); Mon, 6 Feb 2023 02:50:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58162 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230040AbjBFHup (ORCPT ); Mon, 6 Feb 2023 02:50:45 -0500 Received: from NAM02-DM3-obe.outbound.protection.outlook.com (mail-dm3nam02on2083.outbound.protection.outlook.com [40.107.95.83]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C97D11D917; 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Rather than charge pages to both user->locked_vm and mm->pinned_vm this will only charge pages to user->locked_vm. Signed-off-by: Alistair Popple Cc: Jens Axboe Cc: Pavel Begunkov Cc: io-uring@vger.kernel.org Cc: linux-kernel@vger.kernel.org --- include/linux/io_uring_types.h | 4 ++-- io_uring/io_uring.c | 20 +++--------------- io_uring/notif.c | 4 ++-- io_uring/notif.h | 10 +++------ io_uring/rsrc.c | 38 +++-------------------------------- io_uring/rsrc.h | 9 +-------- 6 files changed, 17 insertions(+), 68 deletions(-) diff --git a/include/linux/io_uring_types.h b/include/linux/io_uring_types.h index 128a67a..45ac75d 100644 --- a/include/linux/io_uring_types.h +++ b/include/linux/io_uring_types.h @@ -5,6 +5,7 @@ #include #include #include +#include #include struct io_wq_work_node { @@ -343,8 +344,7 @@ struct io_ring_ctx { struct io_wq_hash *hash_map; /* Only used for accounting purposes */ - struct user_struct *user; - struct mm_struct *mm_account; + struct vm_account vm_account; /* ctx exit and cancelation */ struct llist_head fallback_llist; diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index 0a4efad..912da4f 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -2744,15 +2744,11 @@ static __cold void io_ring_ctx_free(struct io_ring_ctx *ctx) #endif WARN_ON_ONCE(!list_empty(&ctx->ltimeout_list)); - if (ctx->mm_account) { - mmdrop(ctx->mm_account); - ctx->mm_account = NULL; - } + vm_account_release(&ctx->vm_account); io_mem_free(ctx->rings); io_mem_free(ctx->sq_sqes); percpu_ref_exit(&ctx->refs); - free_uid(ctx->user); io_req_caches_free(ctx); if (ctx->hash_map) io_wq_put_hash(ctx->hash_map); @@ -3585,8 +3581,9 @@ static __cold int io_uring_create(unsigned entries, struct io_uring_params *p, ctx->syscall_iopoll = 1; ctx->compat = in_compat_syscall(); - if (!capable(CAP_IPC_LOCK)) - ctx->user = get_uid(current_user()); + vm_account_init(&ctx->vm_account, current, current_user(), + VM_ACCOUNT_USER | + (capable(CAP_IPC_LOCK) ? VM_ACCOUNT_BYPASS : 0)); /* * For SQPOLL, we just need a wakeup, always. For !SQPOLL, if @@ -3619,15 +3616,6 @@ static __cold int io_uring_create(unsigned entries, struct io_uring_params *p, goto err; } - /* - * This is just grabbed for accounting purposes. When a process exits, - * the mm is exited and dropped before the files, hence we need to hang - * on to this mm purely for the purposes of being able to unaccount - * memory (locked/pinned vm). It's not used for anything else. - */ - mmgrab(current->mm); - ctx->mm_account = current->mm; - ret = io_allocate_scq_urings(ctx, p); if (ret) goto err; diff --git a/io_uring/notif.c b/io_uring/notif.c index c4bb793..0f589fa 100644 --- a/io_uring/notif.c +++ b/io_uring/notif.c @@ -17,8 +17,8 @@ static void io_notif_complete_tw_ext(struct io_kiocb *notif, bool *locked) if (nd->zc_report && (nd->zc_copied || !nd->zc_used)) notif->cqe.res |= IORING_NOTIF_USAGE_ZC_COPIED; - if (nd->account_pages && ctx->user) { - __io_unaccount_mem(ctx->user, nd->account_pages); + if (nd->account_pages) { + vm_unaccount_pinned(&ctx->vm_account, nd->account_pages); nd->account_pages = 0; } io_req_task_complete(notif, locked); diff --git a/io_uring/notif.h b/io_uring/notif.h index c88c800..e2cb44a 100644 --- a/io_uring/notif.h +++ b/io_uring/notif.h @@ -43,11 +43,9 @@ static inline int io_notif_account_mem(struct io_kiocb *notif, unsigned len) unsigned nr_pages = (len >> PAGE_SHIFT) + 2; int ret; - if (ctx->user) { - ret = __io_account_mem(ctx->user, nr_pages); - if (ret) - return ret; - nd->account_pages += nr_pages; - } + ret = __io_account_mem(&ctx->vm_account, nr_pages); + if (ret) + return ret; + nd->account_pages += nr_pages; return 0; } diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c index 18de10c..aa44528 100644 --- a/io_uring/rsrc.c +++ b/io_uring/rsrc.c @@ -42,49 +42,19 @@ void io_rsrc_refs_drop(struct io_ring_ctx *ctx) } } -int __io_account_mem(struct user_struct *user, unsigned long nr_pages) +int __io_account_mem(struct vm_account *vm_account, unsigned long nr_pages) { - unsigned long page_limit, cur_pages, new_pages; - - if (!nr_pages) - return 0; - - /* Don't allow more pages than we can safely lock */ - page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; - - cur_pages = atomic_long_read(&user->locked_vm); - do { - new_pages = cur_pages + nr_pages; - if (new_pages > page_limit) - return -ENOMEM; - } while (!atomic_long_try_cmpxchg(&user->locked_vm, - &cur_pages, new_pages)); - return 0; + return vm_account_pinned(vm_account, nr_pages); } static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages) { - if (ctx->user) - __io_unaccount_mem(ctx->user, nr_pages); - - if (ctx->mm_account) - atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm); + vm_unaccount_pinned(&ctx->vm_account, nr_pages); } static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages) { - int ret; - - if (ctx->user) { - ret = __io_account_mem(ctx->user, nr_pages); - if (ret) - return ret; - } - - if (ctx->mm_account) - atomic64_add(nr_pages, &ctx->mm_account->pinned_vm); - - return 0; + return vm_account_pinned(&ctx->vm_account, nr_pages); } static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst, diff --git a/io_uring/rsrc.h b/io_uring/rsrc.h index 2b87436..d8833d0 100644 --- a/io_uring/rsrc.h +++ b/io_uring/rsrc.h @@ -167,12 +167,5 @@ static inline u64 *io_get_tag_slot(struct io_rsrc_data *data, unsigned int idx) int io_files_update(struct io_kiocb *req, unsigned int issue_flags); int io_files_update_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe); -int __io_account_mem(struct user_struct *user, unsigned long nr_pages); - -static inline void __io_unaccount_mem(struct user_struct *user, - unsigned long nr_pages) -{ - atomic_long_sub(nr_pages, &user->locked_vm); -} - +int __io_account_mem(struct vm_account *vm_account, unsigned long nr_pages); #endif