diff options
Diffstat (limited to 'fs/aio.c')
| -rw-r--r-- | fs/aio.c | 1616 |
1 files changed, 1095 insertions, 521 deletions
@@ -5,6 +5,7 @@ * Implements an efficient asynchronous io interface. * * Copyright 2000, 2001, 2002 Red Hat, Inc. All Rights Reserved. + * Copyright 2018 Christoph Hellwig. * * See ../COPYING for licensing terms. */ @@ -18,6 +19,7 @@ #include <linux/export.h> #include <linux/syscalls.h> #include <linux/backing-dev.h> +#include <linux/refcount.h> #include <linux/uio.h> #include <linux/sched/signal.h> @@ -25,7 +27,6 @@ #include <linux/file.h> #include <linux/mm.h> #include <linux/mman.h> -#include <linux/mmu_context.h> #include <linux/percpu.h> #include <linux/slab.h> #include <linux/timer.h> @@ -40,12 +41,15 @@ #include <linux/ramfs.h> #include <linux/percpu-refcount.h> #include <linux/mount.h> +#include <linux/pseudo_fs.h> -#include <asm/kmap_types.h> #include <linux/uaccess.h> +#include <linux/nospec.h> #include "internal.h" +#define KIOCB_KEY 0 + #define AIO_RING_MAGIC 0xa10a10a1 #define AIO_RING_COMPAT_FEATURES 1 #define AIO_RING_INCOMPAT_FEATURES 0 @@ -62,15 +66,21 @@ struct aio_ring { unsigned header_length; /* size of aio_ring */ - struct io_event io_events[0]; + struct io_event io_events[]; }; /* 128 bytes + ring size */ +/* + * Plugging is meant to work with larger batches of IOs. If we don't + * have more than the below, then don't bother setting up a plug. + */ +#define AIO_PLUG_THRESHOLD 2 + #define AIO_RING_PAGES 8 struct kioctx_table { - struct rcu_head rcu; - unsigned nr; - struct kioctx *table[]; + struct rcu_head rcu; + unsigned nr; + struct kioctx __rcu *table[] __counted_by(nr); }; struct kioctx_cpu { @@ -90,7 +100,7 @@ struct kioctx { unsigned long user_id; - struct __percpu kioctx_cpu *cpu; + struct kioctx_cpu __percpu *cpu; /* * For percpu reqs_available, number of slots we move to/from global @@ -112,10 +122,10 @@ struct kioctx { unsigned long mmap_base; unsigned long mmap_size; - struct page **ring_pages; + struct folio **ring_folios; long nr_pages; - struct work_struct free_work; + struct rcu_work free_rwork; /* see free_ioctx() */ /* * signals when all in-flight requests are done @@ -150,36 +160,56 @@ struct kioctx { spinlock_t completion_lock; } ____cacheline_aligned_in_smp; - struct page *internal_pages[AIO_RING_PAGES]; + struct folio *internal_folios[AIO_RING_PAGES]; struct file *aio_ring_file; unsigned id; }; /* - * We use ki_cancel == KIOCB_CANCELLED to indicate that a kiocb has been either - * cancelled or completed (this makes a certain amount of sense because - * successful cancellation - io_cancel() - does deliver the completion to - * userspace). - * - * And since most things don't implement kiocb cancellation and we'd really like - * kiocb completion to be lockless when possible, we use ki_cancel to - * synchronize cancellation and completion - we only set it to KIOCB_CANCELLED - * with xchg() or cmpxchg(), see batch_complete_aio() and kiocb_cancel(). + * First field must be the file pointer in all the + * iocb unions! See also 'struct kiocb' in <linux/fs.h> */ -#define KIOCB_CANCELLED ((void *) (~0ULL)) +struct fsync_iocb { + struct file *file; + struct work_struct work; + bool datasync; + struct cred *creds; +}; + +struct poll_iocb { + struct file *file; + struct wait_queue_head *head; + __poll_t events; + bool cancelled; + bool work_scheduled; + bool work_need_resched; + struct wait_queue_entry wait; + struct work_struct work; +}; +/* + * NOTE! Each of the iocb union members has the file pointer + * as the first entry in their struct definition. So you can + * access the file pointer through any of the sub-structs, + * or directly as just 'ki_filp' in this struct. + */ struct aio_kiocb { - struct kiocb common; + union { + struct file *ki_filp; + struct kiocb rw; + struct fsync_iocb fsync; + struct poll_iocb poll; + }; struct kioctx *ki_ctx; kiocb_cancel_fn *ki_cancel; - struct iocb __user *ki_user_iocb; /* user's aiocb */ - __u64 ki_user_data; /* user's data for completion */ + struct io_event ki_res; struct list_head ki_list; /* the aio core uses this * for cancellation */ + refcount_t ki_refcnt; /* * If the aio_resfd field of the userspace iocb is not zero, @@ -190,9 +220,34 @@ struct aio_kiocb { /*------ sysctl variables----*/ static DEFINE_SPINLOCK(aio_nr_lock); -unsigned long aio_nr; /* current system wide number of aio requests */ -unsigned long aio_max_nr = 0x10000; /* system wide maximum number of aio requests */ +static unsigned long aio_nr; /* current system wide number of aio requests */ +static unsigned long aio_max_nr = 0x10000; /* system wide maximum number of aio requests */ /*----end sysctl variables---*/ +#ifdef CONFIG_SYSCTL +static const struct ctl_table aio_sysctls[] = { + { + .procname = "aio-nr", + .data = &aio_nr, + .maxlen = sizeof(aio_nr), + .mode = 0444, + .proc_handler = proc_doulongvec_minmax, + }, + { + .procname = "aio-max-nr", + .data = &aio_max_nr, + .maxlen = sizeof(aio_max_nr), + .mode = 0644, + .proc_handler = proc_doulongvec_minmax, + }, +}; + +static void __init aio_sysctl_init(void) +{ + register_sysctl_init("fs", aio_sysctls); +} +#else +#define aio_sysctl_init() do { } while (0) +#endif static struct kmem_cache *kiocb_cachep; static struct kmem_cache *kioctx_cachep; @@ -204,47 +259,28 @@ static const struct address_space_operations aio_ctx_aops; static struct file *aio_private_file(struct kioctx *ctx, loff_t nr_pages) { - struct qstr this = QSTR_INIT("[aio]", 5); struct file *file; - struct path path; struct inode *inode = alloc_anon_inode(aio_mnt->mnt_sb); if (IS_ERR(inode)) return ERR_CAST(inode); inode->i_mapping->a_ops = &aio_ctx_aops; - inode->i_mapping->private_data = ctx; + inode->i_mapping->i_private_data = ctx; inode->i_size = PAGE_SIZE * nr_pages; - path.dentry = d_alloc_pseudo(aio_mnt->mnt_sb, &this); - if (!path.dentry) { + file = alloc_file_pseudo(inode, aio_mnt, "[aio]", + O_RDWR, &aio_ring_fops); + if (IS_ERR(file)) iput(inode); - return ERR_PTR(-ENOMEM); - } - path.mnt = mntget(aio_mnt); - - d_instantiate(path.dentry, inode); - file = alloc_file(&path, FMODE_READ | FMODE_WRITE, &aio_ring_fops); - if (IS_ERR(file)) { - path_put(&path); - return file; - } - - file->f_flags = O_RDWR; return file; } -static struct dentry *aio_mount(struct file_system_type *fs_type, - int flags, const char *dev_name, void *data) +static int aio_init_fs_context(struct fs_context *fc) { - static const struct dentry_operations ops = { - .d_dname = simple_dname, - }; - struct dentry *root = mount_pseudo(fs_type, "aio:", NULL, &ops, - AIO_RING_MAGIC); - - if (!IS_ERR(root)) - root->d_sb->s_iflags |= SB_I_NOEXEC; - return root; + if (!init_pseudo(fc, AIO_RING_MAGIC)) + return -ENOMEM; + fc->s_iflags |= SB_I_NOEXEC; + return 0; } /* aio_setup @@ -255,7 +291,7 @@ static int __init aio_setup(void) { static struct file_system_type aio_fs = { .name = "aio", - .mount = aio_mount, + .init_fs_context = aio_init_fs_context, .kill_sb = kill_anon_super, }; aio_mnt = kern_mount(&aio_fs); @@ -264,9 +300,7 @@ static int __init aio_setup(void) kiocb_cachep = KMEM_CACHE(aio_kiocb, SLAB_HWCACHE_ALIGN|SLAB_PANIC); kioctx_cachep = KMEM_CACHE(kioctx,SLAB_HWCACHE_ALIGN|SLAB_PANIC); - - pr_debug("sizeof(struct page) = %zu\n", sizeof(struct page)); - + aio_sysctl_init(); return 0; } __initcall(aio_setup); @@ -281,10 +315,10 @@ static void put_aio_ring_file(struct kioctx *ctx) /* Prevent further access to the kioctx from migratepages */ i_mapping = aio_ring_file->f_mapping; - spin_lock(&i_mapping->private_lock); - i_mapping->private_data = NULL; + spin_lock(&i_mapping->i_private_lock); + i_mapping->i_private_data = NULL; ctx->aio_ring_file = NULL; - spin_unlock(&i_mapping->private_lock); + spin_unlock(&i_mapping->i_private_lock); fput(aio_ring_file); } @@ -300,19 +334,20 @@ static void aio_free_ring(struct kioctx *ctx) put_aio_ring_file(ctx); for (i = 0; i < ctx->nr_pages; i++) { - struct page *page; - pr_debug("pid(%d) [%d] page->count=%d\n", current->pid, i, - page_count(ctx->ring_pages[i])); - page = ctx->ring_pages[i]; - if (!page) + struct folio *folio = ctx->ring_folios[i]; + + if (!folio) continue; - ctx->ring_pages[i] = NULL; - put_page(page); + + pr_debug("pid(%d) [%d] folio->count=%d\n", current->pid, i, + folio_ref_count(folio)); + ctx->ring_folios[i] = NULL; + folio_put(folio); } - if (ctx->ring_pages && ctx->ring_pages != ctx->internal_pages) { - kfree(ctx->ring_pages); - ctx->ring_pages = NULL; + if (ctx->ring_folios && ctx->ring_folios != ctx->internal_folios) { + kfree(ctx->ring_folios); + ctx->ring_folios = NULL; } } @@ -326,10 +361,13 @@ static int aio_ring_mremap(struct vm_area_struct *vma) spin_lock(&mm->ioctx_lock); rcu_read_lock(); table = rcu_dereference(mm->ioctx_table); + if (!table) + goto out_unlock; + for (i = 0; i < table->nr; i++) { struct kioctx *ctx; - ctx = table->table[i]; + ctx = rcu_dereference(table->table[i]); if (ctx && ctx->aio_ring_file == file) { if (!atomic_read(&ctx->dead)) { ctx->user_id = ctx->mmap_base = vma->vm_start; @@ -339,6 +377,7 @@ static int aio_ring_mremap(struct vm_area_struct *vma) } } +out_unlock: rcu_read_unlock(); spin_unlock(&mm->ioctx_lock); return res; @@ -353,31 +392,29 @@ static const struct vm_operations_struct aio_ring_vm_ops = { #endif }; -static int aio_ring_mmap(struct file *file, struct vm_area_struct *vma) +static int aio_ring_mmap_prepare(struct vm_area_desc *desc) { - vma->vm_flags |= VM_DONTEXPAND; - vma->vm_ops = &aio_ring_vm_ops; + desc->vm_flags |= VM_DONTEXPAND; + desc->vm_ops = &aio_ring_vm_ops; return 0; } static const struct file_operations aio_ring_fops = { - .mmap = aio_ring_mmap, + .mmap_prepare = aio_ring_mmap_prepare, }; #if IS_ENABLED(CONFIG_MIGRATION) -static int aio_migratepage(struct address_space *mapping, struct page *new, - struct page *old, enum migrate_mode mode) +static int aio_migrate_folio(struct address_space *mapping, struct folio *dst, + struct folio *src, enum migrate_mode mode) { struct kioctx *ctx; unsigned long flags; pgoff_t idx; - int rc; - - rc = 0; + int rc = 0; - /* mapping->private_lock here protects against the kioctx teardown. */ - spin_lock(&mapping->private_lock); - ctx = mapping->private_data; + /* mapping->i_private_lock here protects against the kioctx teardown. */ + spin_lock(&mapping->i_private_lock); + ctx = mapping->i_private_data; if (!ctx) { rc = -EINVAL; goto out; @@ -392,10 +429,10 @@ static int aio_migratepage(struct address_space *mapping, struct page *new, goto out; } - idx = old->index; + idx = src->index; if (idx < (pgoff_t)ctx->nr_pages) { - /* Make sure the old page hasn't already been changed */ - if (ctx->ring_pages[idx] != old) + /* Make sure the old folio hasn't already been changed */ + if (ctx->ring_folios[idx] != src) rc = -EAGAIN; } else rc = -EINVAL; @@ -404,47 +441,47 @@ static int aio_migratepage(struct address_space *mapping, struct page *new, goto out_unlock; /* Writeback must be complete */ - BUG_ON(PageWriteback(old)); - get_page(new); + BUG_ON(folio_test_writeback(src)); + folio_get(dst); - rc = migrate_page_move_mapping(mapping, new, old, NULL, mode, 1); - if (rc != MIGRATEPAGE_SUCCESS) { - put_page(new); + rc = folio_migrate_mapping(mapping, dst, src, 1); + if (rc) { + folio_put(dst); goto out_unlock; } /* Take completion_lock to prevent other writes to the ring buffer - * while the old page is copied to the new. This prevents new + * while the old folio is copied to the new. This prevents new * events from being lost. */ spin_lock_irqsave(&ctx->completion_lock, flags); - migrate_page_copy(new, old); - BUG_ON(ctx->ring_pages[idx] != old); - ctx->ring_pages[idx] = new; + folio_copy(dst, src); + folio_migrate_flags(dst, src); + BUG_ON(ctx->ring_folios[idx] != src); + ctx->ring_folios[idx] = dst; spin_unlock_irqrestore(&ctx->completion_lock, flags); - /* The old page is no longer accessible. */ - put_page(old); + /* The old folio is no longer accessible. */ + folio_put(src); out_unlock: mutex_unlock(&ctx->ring_lock); out: - spin_unlock(&mapping->private_lock); + spin_unlock(&mapping->i_private_lock); return rc; } +#else +#define aio_migrate_folio NULL #endif static const struct address_space_operations aio_ctx_aops = { - .set_page_dirty = __set_page_dirty_no_writeback, -#if IS_ENABLED(CONFIG_MIGRATION) - .migratepage = aio_migratepage, -#endif + .dirty_folio = noop_dirty_folio, + .migrate_folio = aio_migrate_folio, }; -static int aio_setup_ring(struct kioctx *ctx) +static int aio_setup_ring(struct kioctx *ctx, unsigned int nr_events) { struct aio_ring *ring; - unsigned nr_events = ctx->max_reqs; struct mm_struct *mm = current->mm; unsigned long size, unused; int nr_pages; @@ -471,28 +508,30 @@ static int aio_setup_ring(struct kioctx *ctx) nr_events = (PAGE_SIZE * nr_pages - sizeof(struct aio_ring)) / sizeof(struct io_event); - ctx->ring_pages = ctx->internal_pages; + ctx->ring_folios = ctx->internal_folios; if (nr_pages > AIO_RING_PAGES) { - ctx->ring_pages = kcalloc(nr_pages, sizeof(struct page *), - GFP_KERNEL); - if (!ctx->ring_pages) { + ctx->ring_folios = kcalloc(nr_pages, sizeof(struct folio *), + GFP_KERNEL); + if (!ctx->ring_folios) { put_aio_ring_file(ctx); return -ENOMEM; } } for (i = 0; i < nr_pages; i++) { - struct page *page; - page = find_or_create_page(file->f_mapping, - i, GFP_HIGHUSER | __GFP_ZERO); - if (!page) + struct folio *folio; + + folio = __filemap_get_folio(file->f_mapping, i, + FGP_LOCK | FGP_ACCESSED | FGP_CREAT, + GFP_USER | __GFP_ZERO); + if (IS_ERR(folio)) break; - pr_debug("pid(%d) page[%d]->count=%d\n", - current->pid, i, page_count(page)); - SetPageUptodate(page); - unlock_page(page); - ctx->ring_pages[i] = page; + pr_debug("pid(%d) [%d] folio->count=%d\n", current->pid, i, + folio_ref_count(folio)); + folio_end_read(folio, true); + + ctx->ring_folios[i] = folio; } ctx->nr_pages = i; @@ -504,16 +543,16 @@ static int aio_setup_ring(struct kioctx *ctx) ctx->mmap_size = nr_pages * PAGE_SIZE; pr_debug("attempting mmap of %lu bytes\n", ctx->mmap_size); - if (down_write_killable(&mm->mmap_sem)) { + if (mmap_write_lock_killable(mm)) { ctx->mmap_size = 0; aio_free_ring(ctx); return -EINTR; } - ctx->mmap_base = do_mmap_pgoff(ctx->aio_ring_file, 0, ctx->mmap_size, - PROT_READ | PROT_WRITE, - MAP_SHARED, 0, &unused, NULL); - up_write(&mm->mmap_sem); + ctx->mmap_base = do_mmap(ctx->aio_ring_file, 0, ctx->mmap_size, + PROT_READ | PROT_WRITE, + MAP_SHARED, 0, 0, &unused, NULL); + mmap_write_unlock(mm); if (IS_ERR((void *)ctx->mmap_base)) { ctx->mmap_size = 0; aio_free_ring(ctx); @@ -525,7 +564,7 @@ static int aio_setup_ring(struct kioctx *ctx) ctx->user_id = ctx->mmap_base; ctx->nr_events = nr_events; /* trusted copy */ - ring = kmap_atomic(ctx->ring_pages[0]); + ring = folio_address(ctx->ring_folios[0]); ring->nr = nr_events; /* user copy */ ring->id = ~0U; ring->head = ring->tail = 0; @@ -533,8 +572,7 @@ static int aio_setup_ring(struct kioctx *ctx) ring->compat_features = AIO_RING_COMPAT_FEATURES; ring->incompat_features = AIO_RING_INCOMPAT_FEATURES; ring->header_length = sizeof(struct aio_ring); - kunmap_atomic(ring); - flush_dcache_page(ctx->ring_pages[0]); + flush_dcache_folio(ctx->ring_folios[0]); return 0; } @@ -545,46 +583,40 @@ static int aio_setup_ring(struct kioctx *ctx) void kiocb_set_cancel_fn(struct kiocb *iocb, kiocb_cancel_fn *cancel) { - struct aio_kiocb *req = container_of(iocb, struct aio_kiocb, common); - struct kioctx *ctx = req->ki_ctx; + struct aio_kiocb *req; + struct kioctx *ctx; unsigned long flags; - spin_lock_irqsave(&ctx->ctx_lock, flags); - - if (!req->ki_list.next) - list_add(&req->ki_list, &ctx->active_reqs); - - req->ki_cancel = cancel; - - spin_unlock_irqrestore(&ctx->ctx_lock, flags); -} -EXPORT_SYMBOL(kiocb_set_cancel_fn); - -static int kiocb_cancel(struct aio_kiocb *kiocb) -{ - kiocb_cancel_fn *old, *cancel; - /* - * Don't want to set kiocb->ki_cancel = KIOCB_CANCELLED unless it - * actually has a cancel function, hence the cmpxchg() + * kiocb didn't come from aio or is neither a read nor a write, hence + * ignore it. */ + if (!(iocb->ki_flags & IOCB_AIO_RW)) + return; + + req = container_of(iocb, struct aio_kiocb, rw); - cancel = ACCESS_ONCE(kiocb->ki_cancel); - do { - if (!cancel || cancel == KIOCB_CANCELLED) - return -EINVAL; + if (WARN_ON_ONCE(!list_empty(&req->ki_list))) + return; - old = cancel; - cancel = cmpxchg(&kiocb->ki_cancel, old, KIOCB_CANCELLED); - } while (cancel != old); + ctx = req->ki_ctx; - return cancel(&kiocb->common); + spin_lock_irqsave(&ctx->ctx_lock, flags); + list_add_tail(&req->ki_list, &ctx->active_reqs); + req->ki_cancel = cancel; + spin_unlock_irqrestore(&ctx->ctx_lock, flags); } +EXPORT_SYMBOL(kiocb_set_cancel_fn); +/* + * free_ioctx() should be RCU delayed to synchronize against the RCU + * protected lookup_ioctx() and also needs process context to call + * aio_free_ring(). Use rcu_work. + */ static void free_ioctx(struct work_struct *work) { - struct kioctx *ctx = container_of(work, struct kioctx, free_work); - + struct kioctx *ctx = container_of(to_rcu_work(work), struct kioctx, + free_rwork); pr_debug("freeing %p\n", ctx); aio_free_ring(ctx); @@ -602,8 +634,9 @@ static void free_ioctx_reqs(struct percpu_ref *ref) if (ctx->rq_wait && atomic_dec_and_test(&ctx->rq_wait->count)) complete(&ctx->rq_wait->comp); - INIT_WORK(&ctx->free_work, free_ioctx); - schedule_work(&ctx->free_work); + /* Synchronize against RCU protected table->table[] dereferences */ + INIT_RCU_WORK(&ctx->free_rwork, free_ioctx); + queue_rcu_work(system_percpu_wq, &ctx->free_rwork); } /* @@ -621,9 +654,8 @@ static void free_ioctx_users(struct percpu_ref *ref) while (!list_empty(&ctx->active_reqs)) { req = list_first_entry(&ctx->active_reqs, struct aio_kiocb, ki_list); - + req->ki_cancel(&req->rw); list_del_init(&req->ki_list); - kiocb_cancel(req); } spin_unlock_irq(&ctx->ctx_lock); @@ -644,26 +676,24 @@ static int ioctx_add_table(struct kioctx *ctx, struct mm_struct *mm) while (1) { if (table) for (i = 0; i < table->nr; i++) - if (!table->table[i]) { + if (!rcu_access_pointer(table->table[i])) { ctx->id = i; - table->table[i] = ctx; + rcu_assign_pointer(table->table[i], ctx); spin_unlock(&mm->ioctx_lock); /* While kioctx setup is in progress, * we are protected from page migration - * changes ring_pages by ->ring_lock. + * changes ring_folios by ->ring_lock. */ - ring = kmap_atomic(ctx->ring_pages[0]); + ring = folio_address(ctx->ring_folios[0]); ring->id = ctx->id; - kunmap_atomic(ring); return 0; } new_nr = (table ? table->nr : 1) * 4; spin_unlock(&mm->ioctx_lock); - table = kzalloc(sizeof(*table) + sizeof(struct kioctx *) * - new_nr, GFP_KERNEL); + table = kzalloc(struct_size(table, table, new_nr), GFP_KERNEL); if (!table) return -ENOMEM; @@ -707,6 +737,12 @@ static struct kioctx *ioctx_alloc(unsigned nr_events) int err = -ENOMEM; /* + * Store the original nr_events -- what userspace passed to io_setup(), + * for counting against the global limit -- before it changes. + */ + unsigned int max_reqs = nr_events; + + /* * We keep track of the number of available ringbuffer slots, to prevent * overflow (reqs_available), and we also use percpu counters for this. * @@ -724,14 +760,14 @@ static struct kioctx *ioctx_alloc(unsigned nr_events) return ERR_PTR(-EINVAL); } - if (!nr_events || (unsigned long)nr_events > (aio_max_nr * 2UL)) + if (!nr_events || (unsigned long)max_reqs > aio_max_nr) return ERR_PTR(-EAGAIN); ctx = kmem_cache_zalloc(kioctx_cachep, GFP_KERNEL); if (!ctx) return ERR_PTR(-ENOMEM); - ctx->max_reqs = nr_events; + ctx->max_reqs = max_reqs; spin_lock_init(&ctx->ctx_lock); spin_lock_init(&ctx->completion_lock); @@ -753,7 +789,7 @@ static struct kioctx *ioctx_alloc(unsigned nr_events) if (!ctx->cpu) goto err; - err = aio_setup_ring(ctx); + err = aio_setup_ring(ctx, nr_events); if (err < 0) goto err; @@ -764,8 +800,8 @@ static struct kioctx *ioctx_alloc(unsigned nr_events) /* limit the number of system wide aios */ spin_lock(&aio_nr_lock); - if (aio_nr + nr_events > (aio_max_nr * 2UL) || - aio_nr + nr_events < aio_nr) { + if (aio_nr + ctx->max_reqs > aio_max_nr || + aio_nr + ctx->max_reqs < aio_nr) { spin_unlock(&aio_nr_lock); err = -EAGAIN; goto err_ctx; @@ -821,11 +857,11 @@ static int kill_ioctx(struct mm_struct *mm, struct kioctx *ctx, } table = rcu_dereference_raw(mm->ioctx_table); - WARN_ON(ctx != table->table[ctx->id]); - table->table[ctx->id] = NULL; + WARN_ON(ctx != rcu_access_pointer(table->table[ctx->id])); + RCU_INIT_POINTER(table->table[ctx->id], NULL); spin_unlock(&mm->ioctx_lock); - /* percpu_ref_kill() will do the necessary call_rcu() */ + /* free_ioctx_reqs() will do the necessary RCU synchronization */ wake_up_all(&ctx->wait); /* @@ -867,7 +903,8 @@ void exit_aio(struct mm_struct *mm) skipped = 0; for (i = 0; i < table->nr; ++i) { - struct kioctx *ctx = table->table[i]; + struct kioctx *ctx = + rcu_dereference_protected(table->table[i], true); if (!ctx) { skipped++; @@ -911,7 +948,7 @@ static void put_reqs_available(struct kioctx *ctx, unsigned nr) local_irq_restore(flags); } -static bool get_reqs_available(struct kioctx *ctx) +static bool __get_reqs_available(struct kioctx *ctx) { struct kioctx_cpu *kcpu; bool ret = false; @@ -920,16 +957,13 @@ static bool get_reqs_available(struct kioctx *ctx) local_irq_save(flags); kcpu = this_cpu_ptr(ctx->cpu); if (!kcpu->reqs_available) { - int old, avail = atomic_read(&ctx->reqs_available); + int avail = atomic_read(&ctx->reqs_available); do { if (avail < ctx->req_batch) goto out; - - old = avail; - avail = atomic_cmpxchg(&ctx->reqs_available, - avail, avail - ctx->req_batch); - } while (avail != old); + } while (!atomic_try_cmpxchg(&ctx->reqs_available, + &avail, avail - ctx->req_batch)); kcpu->reqs_available += ctx->req_batch; } @@ -993,9 +1027,8 @@ static void user_refill_reqs_available(struct kioctx *ctx) * against ctx->completed_events below will make sure we do the * safe/right thing. */ - ring = kmap_atomic(ctx->ring_pages[0]); + ring = folio_address(ctx->ring_folios[0]); head = ring->head; - kunmap_atomic(ring); refill_reqs_available(ctx, head, ctx->tail); } @@ -1003,40 +1036,40 @@ static void user_refill_reqs_available(struct kioctx *ctx) spin_unlock_irq(&ctx->completion_lock); } +static bool get_reqs_available(struct kioctx *ctx) +{ + if (__get_reqs_available(ctx)) + return true; + user_refill_reqs_available(ctx); + return __get_reqs_available(ctx); +} + /* aio_get_req * Allocate a slot for an aio request. * Returns NULL if no requests are free. + * + * The refcount is initialized to 2 - one for the async op completion, + * one for the synchronous code that does this. */ static inline struct aio_kiocb *aio_get_req(struct kioctx *ctx) { struct aio_kiocb *req; - if (!get_reqs_available(ctx)) { - user_refill_reqs_available(ctx); - if (!get_reqs_available(ctx)) - return NULL; - } - - req = kmem_cache_alloc(kiocb_cachep, GFP_KERNEL|__GFP_ZERO); + req = kmem_cache_alloc(kiocb_cachep, GFP_KERNEL); if (unlikely(!req)) - goto out_put; + return NULL; - percpu_ref_get(&ctx->reqs); + if (unlikely(!get_reqs_available(ctx))) { + kmem_cache_free(kiocb_cachep, req); + return NULL; + } + percpu_ref_get(&ctx->reqs); req->ki_ctx = ctx; + INIT_LIST_HEAD(&req->ki_list); + refcount_set(&req->ki_refcnt, 2); + req->ki_eventfd = NULL; return req; -out_put: - put_reqs_available(ctx, 1); - return NULL; -} - -static void kiocb_free(struct aio_kiocb *req) -{ - if (req->common.ki_filp) - fput(req->common.ki_filp); - if (req->ki_eventfd != NULL) - eventfd_ctx_put(req->ki_eventfd); - kmem_cache_free(kiocb_cachep, req); } static struct kioctx *lookup_ioctx(unsigned long ctx_id) @@ -1056,57 +1089,43 @@ static struct kioctx *lookup_ioctx(unsigned long ctx_id) if (!table || id >= table->nr) goto out; - ctx = table->table[id]; + id = array_index_nospec(id, table->nr); + ctx = rcu_dereference(table->table[id]); if (ctx && ctx->user_id == ctx_id) { - percpu_ref_get(&ctx->users); - ret = ctx; + if (percpu_ref_tryget_live(&ctx->users)) + ret = ctx; } out: rcu_read_unlock(); return ret; } +static inline void iocb_destroy(struct aio_kiocb *iocb) +{ + if (iocb->ki_eventfd) + eventfd_ctx_put(iocb->ki_eventfd); + if (iocb->ki_filp) + fput(iocb->ki_filp); + percpu_ref_put(&iocb->ki_ctx->reqs); + kmem_cache_free(kiocb_cachep, iocb); +} + +struct aio_waiter { + struct wait_queue_entry w; + size_t min_nr; +}; + /* aio_complete * Called when the io request on the given iocb is complete. */ -static void aio_complete(struct kiocb *kiocb, long res, long res2) +static void aio_complete(struct aio_kiocb *iocb) { - struct aio_kiocb *iocb = container_of(kiocb, struct aio_kiocb, common); struct kioctx *ctx = iocb->ki_ctx; struct aio_ring *ring; struct io_event *ev_page, *event; - unsigned tail, pos, head; + unsigned tail, pos, head, avail; unsigned long flags; - if (kiocb->ki_flags & IOCB_WRITE) { - struct file *file = kiocb->ki_filp; - - /* - * Tell lockdep we inherited freeze protection from submission - * thread. - */ - if (S_ISREG(file_inode(file)->i_mode)) - __sb_writers_acquired(file_inode(file)->i_sb, SB_FREEZE_WRITE); - file_end_write(file); - } - - /* - * Special case handling for sync iocbs: - * - events go directly into the iocb for fast handling - * - the sync task with the iocb in its stack holds the single iocb - * ref, no other paths have a way to get another ref - * - the sync task helpfully left a reference to itself in the iocb - */ - BUG_ON(is_sync_kiocb(kiocb)); - - if (iocb->ki_list.next) { - unsigned long flags; - - spin_lock_irqsave(&ctx->ctx_lock, flags); - list_del(&iocb->ki_list); - spin_unlock_irqrestore(&ctx->ctx_lock, flags); - } - /* * Add a completion event to the ring buffer. Must be done holding * ctx->completion_lock to prevent other code from messing with the tail @@ -1120,20 +1139,16 @@ static void aio_complete(struct kiocb *kiocb, long res, long res2) if (++tail >= ctx->nr_events) tail = 0; - ev_page = kmap_atomic(ctx->ring_pages[pos / AIO_EVENTS_PER_PAGE]); + ev_page = folio_address(ctx->ring_folios[pos / AIO_EVENTS_PER_PAGE]); event = ev_page + pos % AIO_EVENTS_PER_PAGE; - event->obj = (u64)(unsigned long)iocb->ki_user_iocb; - event->data = iocb->ki_user_data; - event->res = res; - event->res2 = res2; + *event = iocb->ki_res; - kunmap_atomic(ev_page); - flush_dcache_page(ctx->ring_pages[pos / AIO_EVENTS_PER_PAGE]); + flush_dcache_folio(ctx->ring_folios[pos / AIO_EVENTS_PER_PAGE]); - pr_debug("%p[%u]: %p: %p %Lx %lx %lx\n", - ctx, tail, iocb, iocb->ki_user_iocb, iocb->ki_user_data, - res, res2); + pr_debug("%p[%u]: %p: %p %Lx %Lx %Lx\n", ctx, tail, iocb, + (void __user *)(unsigned long)iocb->ki_res.obj, + iocb->ki_res.data, iocb->ki_res.res, iocb->ki_res.res2); /* after flagging the request as done, we * must never even look at it again @@ -1142,15 +1157,18 @@ static void aio_complete(struct kiocb *kiocb, long res, long res2) ctx->tail = tail; - ring = kmap_atomic(ctx->ring_pages[0]); + ring = folio_address(ctx->ring_folios[0]); head = ring->head; ring->tail = tail; - kunmap_atomic(ring); - flush_dcache_page(ctx->ring_pages[0]); + flush_dcache_folio(ctx->ring_folios[0]); ctx->completed_events++; if (ctx->completed_events > 1) refill_reqs_available(ctx, head, tail); + + avail = tail > head + ? tail - head + : tail + ctx->nr_events - head; spin_unlock_irqrestore(&ctx->completion_lock, flags); pr_debug("added to ring %p at [%u]\n", iocb, tail); @@ -1160,11 +1178,8 @@ static void aio_complete(struct kiocb *kiocb, long res, long res2) * eventfd. The eventfd_signal() function is safe to be called * from IRQ context. */ - if (iocb->ki_eventfd != NULL) - eventfd_signal(iocb->ki_eventfd, 1); - - /* everything turned out well, dispose of the aiocb. */ - kiocb_free(iocb); + if (iocb->ki_eventfd) + eventfd_signal(iocb->ki_eventfd); /* * We have to order our ring_info tail store above and test @@ -1174,10 +1189,26 @@ static void aio_complete(struct kiocb *kiocb, long res, long res2) */ smp_mb(); - if (waitqueue_active(&ctx->wait)) - wake_up(&ctx->wait); + if (waitqueue_active(&ctx->wait)) { + struct aio_waiter *curr, *next; + unsigned long flags; - percpu_ref_put(&ctx->reqs); + spin_lock_irqsave(&ctx->wait.lock, flags); + list_for_each_entry_safe(curr, next, &ctx->wait.head, w.entry) + if (avail >= curr->min_nr) { + wake_up_process(curr->w.private); + list_del_init_careful(&curr->w.entry); + } + spin_unlock_irqrestore(&ctx->wait.lock, flags); + } +} + +static inline void iocb_put(struct aio_kiocb *iocb) +{ + if (refcount_dec_and_test(&iocb->ki_refcnt)) { + aio_complete(iocb); + iocb_destroy(iocb); + } } /* aio_read_events_ring @@ -1201,11 +1232,10 @@ static long aio_read_events_ring(struct kioctx *ctx, sched_annotate_sleep(); mutex_lock(&ctx->ring_lock); - /* Access to ->ring_pages here is protected by ctx->ring_lock. */ - ring = kmap_atomic(ctx->ring_pages[0]); + /* Access to ->ring_folios here is protected by ctx->ring_lock. */ + ring = folio_address(ctx->ring_folios[0]); head = ring->head; tail = ring->tail; - kunmap_atomic(ring); /* * Ensure that once we've read the current tail pointer, that @@ -1224,24 +1254,22 @@ static long aio_read_events_ring(struct kioctx *ctx, while (ret < nr) { long avail; struct io_event *ev; - struct page *page; + struct folio *folio; avail = (head <= tail ? tail : ctx->nr_events) - head; if (head == tail) break; - avail = min(avail, nr - ret); - avail = min_t(long, avail, AIO_EVENTS_PER_PAGE - - ((head + AIO_EVENTS_OFFSET) % AIO_EVENTS_PER_PAGE)); - pos = head + AIO_EVENTS_OFFSET; - page = ctx->ring_pages[pos / AIO_EVENTS_PER_PAGE]; + folio = ctx->ring_folios[pos / AIO_EVENTS_PER_PAGE]; pos %= AIO_EVENTS_PER_PAGE; - ev = kmap(page); + avail = min(avail, nr - ret); + avail = min_t(long, avail, AIO_EVENTS_PER_PAGE - pos); + + ev = folio_address(folio); copy_ret = copy_to_user(event + ret, ev + pos, sizeof(*ev) * avail); - kunmap(page); if (unlikely(copy_ret)) { ret = -EFAULT; @@ -1253,10 +1281,9 @@ static long aio_read_events_ring(struct kioctx *ctx, head %= ctx->nr_events; } - ring = kmap_atomic(ctx->ring_pages[0]); + ring = folio_address(ctx->ring_folios[0]); ring->head = head; - kunmap_atomic(ring); - flush_dcache_page(ctx->ring_pages[0]); + flush_dcache_folio(ctx->ring_folios[0]); pr_debug("%li h%u t%u\n", ret, head, tail); out: @@ -1284,19 +1311,11 @@ static bool aio_read_events(struct kioctx *ctx, long min_nr, long nr, static long read_events(struct kioctx *ctx, long min_nr, long nr, struct io_event __user *event, - struct timespec __user *timeout) + ktime_t until) { - ktime_t until = KTIME_MAX; - long ret = 0; - - if (timeout) { - struct timespec ts; - - if (unlikely(copy_from_user(&ts, timeout, sizeof(ts)))) - return -EFAULT; - - until = timespec_to_ktime(ts); - } + struct hrtimer_sleeper t; + struct aio_waiter w; + long ret = 0, ret2 = 0; /* * Note that aio_read_events() is being called as the conditional - i.e. @@ -1312,15 +1331,37 @@ static long read_events(struct kioctx *ctx, long min_nr, long nr, * the ringbuffer empty. So in practice we should be ok, but it's * something to be aware of when touching this code. */ - if (until == 0) - aio_read_events(ctx, min_nr, nr, event, &ret); - else - wait_event_interruptible_hrtimeout(ctx->wait, - aio_read_events(ctx, min_nr, nr, event, &ret), - until); + aio_read_events(ctx, min_nr, nr, event, &ret); + if (until == 0 || ret < 0 || ret >= min_nr) + return ret; - if (!ret && signal_pending(current)) - ret = -EINTR; + hrtimer_setup_sleeper_on_stack(&t, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + if (until != KTIME_MAX) { + hrtimer_set_expires_range_ns(&t.timer, until, current->timer_slack_ns); + hrtimer_sleeper_start_expires(&t, HRTIMER_MODE_REL); + } + + init_wait(&w.w); + + while (1) { + unsigned long nr_got = ret; + + w.min_nr = min_nr - ret; + + ret2 = prepare_to_wait_event(&ctx->wait, &w.w, TASK_INTERRUPTIBLE); + if (!ret2 && !t.task) + ret2 = -ETIME; + + if (aio_read_events(ctx, min_nr, nr, event, &ret) || ret2) + break; + + if (nr_got == ret) + schedule(); + } + + finish_wait(&ctx->wait, &w.w); + hrtimer_cancel(&t.timer); + destroy_hrtimer_on_stack(&t.timer); return ret; } @@ -1437,30 +1478,91 @@ SYSCALL_DEFINE1(io_destroy, aio_context_t, ctx) return -EINVAL; } -static int aio_setup_rw(int rw, struct iocb *iocb, struct iovec **iovec, - bool vectored, bool compat, struct iov_iter *iter) +static void aio_remove_iocb(struct aio_kiocb *iocb) +{ + struct kioctx *ctx = iocb->ki_ctx; + unsigned long flags; + + spin_lock_irqsave(&ctx->ctx_lock, flags); + list_del(&iocb->ki_list); + spin_unlock_irqrestore(&ctx->ctx_lock, flags); +} + +static void aio_complete_rw(struct kiocb *kiocb, long res) +{ + struct aio_kiocb *iocb = container_of(kiocb, struct aio_kiocb, rw); + + if (!list_empty_careful(&iocb->ki_list)) + aio_remove_iocb(iocb); + + if (kiocb->ki_flags & IOCB_WRITE) { + struct inode *inode = file_inode(kiocb->ki_filp); + + if (S_ISREG(inode->i_mode)) + kiocb_end_write(kiocb); + } + + iocb->ki_res.res = res; + iocb->ki_res.res2 = 0; + iocb_put(iocb); +} + +static int aio_prep_rw(struct kiocb *req, const struct iocb *iocb, int rw_type) +{ + int ret; + + req->ki_write_stream = 0; + req->ki_complete = aio_complete_rw; + req->private = NULL; + req->ki_pos = iocb->aio_offset; + req->ki_flags = req->ki_filp->f_iocb_flags | IOCB_AIO_RW; + if (iocb->aio_flags & IOCB_FLAG_RESFD) + req->ki_flags |= IOCB_EVENTFD; + if (iocb->aio_flags & IOCB_FLAG_IOPRIO) { + /* + * If the IOCB_FLAG_IOPRIO flag of aio_flags is set, then + * aio_reqprio is interpreted as an I/O scheduling + * class and priority. + */ + ret = ioprio_check_cap(iocb->aio_reqprio); + if (ret) { + pr_debug("aio ioprio check cap error: %d\n", ret); + return ret; + } + + req->ki_ioprio = iocb->aio_reqprio; + } else + req->ki_ioprio = get_current_ioprio(); + + ret = kiocb_set_rw_flags(req, iocb->aio_rw_flags, rw_type); + if (unlikely(ret)) + return ret; + + req->ki_flags &= ~IOCB_HIPRI; /* no one is going to poll for this I/O */ + return 0; +} + +static ssize_t aio_setup_rw(int rw, const struct iocb *iocb, + struct iovec **iovec, bool vectored, bool compat, + struct iov_iter *iter) { void __user *buf = (void __user *)(uintptr_t)iocb->aio_buf; size_t len = iocb->aio_nbytes; if (!vectored) { - ssize_t ret = import_single_range(rw, buf, len, *iovec, iter); + ssize_t ret = import_ubuf(rw, buf, len, iter); *iovec = NULL; return ret; } -#ifdef CONFIG_COMPAT - if (compat) - return compat_import_iovec(rw, buf, len, UIO_FASTIOV, iovec, - iter); -#endif - return import_iovec(rw, buf, len, UIO_FASTIOV, iovec, iter); + + return __import_iovec(rw, buf, len, UIO_FASTIOV, iovec, iter, compat); } -static inline ssize_t aio_ret(struct kiocb *req, ssize_t ret) +static inline void aio_rw_done(struct kiocb *req, ssize_t ret) { switch (ret) { case -EIOCBQUEUED: - return ret; + break; case -ERESTARTSYS: case -ERESTARTNOINTR: case -ERESTARTNOHAND: @@ -1470,226 +1572,499 @@ static inline ssize_t aio_ret(struct kiocb *req, ssize_t ret) * may be already running. Just fail this IO with EINTR. */ ret = -EINTR; - /*FALLTHRU*/ + fallthrough; default: - aio_complete(req, ret, 0); - return 0; + req->ki_complete(req, ret); } } -static ssize_t aio_read(struct kiocb *req, struct iocb *iocb, bool vectored, - bool compat) +static int aio_read(struct kiocb *req, const struct iocb *iocb, + bool vectored, bool compat) { - struct file *file = req->ki_filp; struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs; struct iov_iter iter; - ssize_t ret; + struct file *file; + int ret; + ret = aio_prep_rw(req, iocb, READ); + if (ret) + return ret; + file = req->ki_filp; if (unlikely(!(file->f_mode & FMODE_READ))) return -EBADF; if (unlikely(!file->f_op->read_iter)) return -EINVAL; - ret = aio_setup_rw(READ, iocb, &iovec, vectored, compat, &iter); - if (ret) + ret = aio_setup_rw(ITER_DEST, iocb, &iovec, vectored, compat, &iter); + if (ret < 0) return ret; ret = rw_verify_area(READ, file, &req->ki_pos, iov_iter_count(&iter)); if (!ret) - ret = aio_ret(req, call_read_iter(file, req, &iter)); + aio_rw_done(req, file->f_op->read_iter(req, &iter)); kfree(iovec); return ret; } -static ssize_t aio_write(struct kiocb *req, struct iocb *iocb, bool vectored, - bool compat) +static int aio_write(struct kiocb *req, const struct iocb *iocb, + bool vectored, bool compat) { - struct file *file = req->ki_filp; struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs; struct iov_iter iter; - ssize_t ret; + struct file *file; + int ret; + + ret = aio_prep_rw(req, iocb, WRITE); + if (ret) + return ret; + file = req->ki_filp; if (unlikely(!(file->f_mode & FMODE_WRITE))) return -EBADF; if (unlikely(!file->f_op->write_iter)) return -EINVAL; - ret = aio_setup_rw(WRITE, iocb, &iovec, vectored, compat, &iter); - if (ret) + ret = aio_setup_rw(ITER_SOURCE, iocb, &iovec, vectored, compat, &iter); + if (ret < 0) return ret; ret = rw_verify_area(WRITE, file, &req->ki_pos, iov_iter_count(&iter)); if (!ret) { - req->ki_flags |= IOCB_WRITE; - file_start_write(file); - ret = aio_ret(req, call_write_iter(file, req, &iter)); - /* - * We release freeze protection in aio_complete(). Fool lockdep - * by telling it the lock got released so that it doesn't - * complain about held lock when we return to userspace. - */ if (S_ISREG(file_inode(file)->i_mode)) - __sb_writers_release(file_inode(file)->i_sb, SB_FREEZE_WRITE); + kiocb_start_write(req); + req->ki_flags |= IOCB_WRITE; + aio_rw_done(req, file->f_op->write_iter(req, &iter)); } kfree(iovec); return ret; } -static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, - struct iocb *iocb, bool compat) +static void aio_fsync_work(struct work_struct *work) { - struct aio_kiocb *req; - struct file *file; - ssize_t ret; + struct aio_kiocb *iocb = container_of(work, struct aio_kiocb, fsync.work); - /* enforce forwards compatibility on users */ - if (unlikely(iocb->aio_reserved2)) { - pr_debug("EINVAL: reserve field set\n"); + scoped_with_creds(iocb->fsync.creds) + iocb->ki_res.res = vfs_fsync(iocb->fsync.file, iocb->fsync.datasync); + + put_cred(iocb->fsync.creds); + iocb_put(iocb); +} + +static int aio_fsync(struct fsync_iocb *req, const struct iocb *iocb, + bool datasync) +{ + if (unlikely(iocb->aio_buf || iocb->aio_offset || iocb->aio_nbytes || + iocb->aio_rw_flags)) return -EINVAL; - } - /* prevent overflows */ - if (unlikely( - (iocb->aio_buf != (unsigned long)iocb->aio_buf) || - (iocb->aio_nbytes != (size_t)iocb->aio_nbytes) || - ((ssize_t)iocb->aio_nbytes < 0) - )) { - pr_debug("EINVAL: overflow check\n"); + if (unlikely(!req->file->f_op->fsync)) return -EINVAL; + + req->creds = prepare_creds(); + if (!req->creds) + return -ENOMEM; + + req->datasync = datasync; + INIT_WORK(&req->work, aio_fsync_work); + schedule_work(&req->work); + return 0; +} + +static void aio_poll_put_work(struct work_struct *work) +{ + struct poll_iocb *req = container_of(work, struct poll_iocb, work); + struct aio_kiocb *iocb = container_of(req, struct aio_kiocb, poll); + + iocb_put(iocb); +} + +/* + * Safely lock the waitqueue which the request is on, synchronizing with the + * case where the ->poll() provider decides to free its waitqueue early. + * + * Returns true on success, meaning that req->head->lock was locked, req->wait + * is on req->head, and an RCU read lock was taken. Returns false if the + * request was already removed from its waitqueue (which might no longer exist). + */ +static bool poll_iocb_lock_wq(struct poll_iocb *req) +{ + wait_queue_head_t *head; + + /* + * While we hold the waitqueue lock and the waitqueue is nonempty, + * wake_up_pollfree() will wait for us. However, taking the waitqueue + * lock in the first place can race with the waitqueue being freed. + * + * We solve this as eventpoll does: by taking advantage of the fact that + * all users of wake_up_pollfree() will RCU-delay the actual free. If + * we enter rcu_read_lock() and see that the pointer to the queue is + * non-NULL, we can then lock it without the memory being freed out from + * under us, then check whether the request is still on the queue. + * + * Keep holding rcu_read_lock() as long as we hold the queue lock, in + * case the caller deletes the entry from the queue, leaving it empty. + * In that case, only RCU prevents the queue memory from being freed. + */ + rcu_read_lock(); + head = smp_load_acquire(&req->head); + if (head) { + spin_lock(&head->lock); + if (!list_empty(&req->wait.entry)) + return true; + spin_unlock(&head->lock); } + rcu_read_unlock(); + return false; +} - req = aio_get_req(ctx); - if (unlikely(!req)) - return -EAGAIN; +static void poll_iocb_unlock_wq(struct poll_iocb *req) +{ + spin_unlock(&req->head->lock); + rcu_read_unlock(); +} + +static void aio_poll_complete_work(struct work_struct *work) +{ + struct poll_iocb *req = container_of(work, struct poll_iocb, work); + struct aio_kiocb *iocb = container_of(req, struct aio_kiocb, poll); + struct poll_table_struct pt = { ._key = req->events }; + struct kioctx *ctx = iocb->ki_ctx; + __poll_t mask = 0; + + if (!READ_ONCE(req->cancelled)) + mask = vfs_poll(req->file, &pt) & req->events; + + /* + * Note that ->ki_cancel callers also delete iocb from active_reqs after + * calling ->ki_cancel. We need the ctx_lock roundtrip here to + * synchronize with them. In the cancellation case the list_del_init + * itself is not actually needed, but harmless so we keep it in to + * avoid further branches in the fast path. + */ + spin_lock_irq(&ctx->ctx_lock); + if (poll_iocb_lock_wq(req)) { + if (!mask && !READ_ONCE(req->cancelled)) { + /* + * The request isn't actually ready to be completed yet. + * Reschedule completion if another wakeup came in. + */ + if (req->work_need_resched) { + schedule_work(&req->work); + req->work_need_resched = false; + } else { + req->work_scheduled = false; + } + poll_iocb_unlock_wq(req); + spin_unlock_irq(&ctx->ctx_lock); + return; + } + list_del_init(&req->wait.entry); + poll_iocb_unlock_wq(req); + } /* else, POLLFREE has freed the waitqueue, so we must complete */ + list_del_init(&iocb->ki_list); + iocb->ki_res.res = mangle_poll(mask); + spin_unlock_irq(&ctx->ctx_lock); + + iocb_put(iocb); +} + +/* assumes we are called with irqs disabled */ +static int aio_poll_cancel(struct kiocb *iocb) +{ + struct aio_kiocb *aiocb = container_of(iocb, struct aio_kiocb, rw); + struct poll_iocb *req = &aiocb->poll; + + if (poll_iocb_lock_wq(req)) { + WRITE_ONCE(req->cancelled, true); + if (!req->work_scheduled) { + schedule_work(&aiocb->poll.work); + req->work_scheduled = true; + } + poll_iocb_unlock_wq(req); + } /* else, the request was force-cancelled by POLLFREE already */ + + return 0; +} + +static int aio_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync, + void *key) +{ + struct poll_iocb *req = container_of(wait, struct poll_iocb, wait); + struct aio_kiocb *iocb = container_of(req, struct aio_kiocb, poll); + __poll_t mask = key_to_poll(key); + unsigned long flags; + + /* for instances that support it check for an event match first: */ + if (mask && !(mask & req->events)) + return 0; + + /* + * Complete the request inline if possible. This requires that three + * conditions be met: + * 1. An event mask must have been passed. If a plain wakeup was done + * instead, then mask == 0 and we have to call vfs_poll() to get + * the events, so inline completion isn't possible. + * 2. The completion work must not have already been scheduled. + * 3. ctx_lock must not be busy. We have to use trylock because we + * already hold the waitqueue lock, so this inverts the normal + * locking order. Use irqsave/irqrestore because not all + * filesystems (e.g. fuse) call this function with IRQs disabled, + * yet IRQs have to be disabled before ctx_lock is obtained. + */ + if (mask && !req->work_scheduled && + spin_trylock_irqsave(&iocb->ki_ctx->ctx_lock, flags)) { + struct kioctx *ctx = iocb->ki_ctx; - req->common.ki_filp = file = fget(iocb->aio_fildes); - if (unlikely(!req->common.ki_filp)) { - ret = -EBADF; - goto out_put_req; + list_del_init(&req->wait.entry); + list_del(&iocb->ki_list); + iocb->ki_res.res = mangle_poll(mask); + if (iocb->ki_eventfd && !eventfd_signal_allowed()) { + iocb = NULL; + INIT_WORK(&req->work, aio_poll_put_work); + schedule_work(&req->work); + } + spin_unlock_irqrestore(&ctx->ctx_lock, flags); + if (iocb) + iocb_put(iocb); + } else { + /* + * Schedule the completion work if needed. If it was already + * scheduled, record that another wakeup came in. + * + * Don't remove the request from the waitqueue here, as it might + * not actually be complete yet (we won't know until vfs_poll() + * is called), and we must not miss any wakeups. POLLFREE is an + * exception to this; see below. + */ + if (req->work_scheduled) { + req->work_need_resched = true; + } else { + schedule_work(&req->work); + req->work_scheduled = true; + } + + /* + * If the waitqueue is being freed early but we can't complete + * the request inline, we have to tear down the request as best + * we can. That means immediately removing the request from its + * waitqueue and preventing all further accesses to the + * waitqueue via the request. We also need to schedule the + * completion work (done above). Also mark the request as + * cancelled, to potentially skip an unneeded call to ->poll(). + */ + if (mask & POLLFREE) { + WRITE_ONCE(req->cancelled, true); + list_del_init(&req->wait.entry); + + /* + * Careful: this *must* be the last step, since as soon + * as req->head is NULL'ed out, the request can be + * completed and freed, since aio_poll_complete_work() + * will no longer need to take the waitqueue lock. + */ + smp_store_release(&req->head, NULL); + } } - req->common.ki_pos = iocb->aio_offset; - req->common.ki_complete = aio_complete; - req->common.ki_flags = iocb_flags(req->common.ki_filp); - req->common.ki_hint = file_write_hint(file); + return 1; +} + +struct aio_poll_table { + struct poll_table_struct pt; + struct aio_kiocb *iocb; + bool queued; + int error; +}; + +static void +aio_poll_queue_proc(struct file *file, struct wait_queue_head *head, + struct poll_table_struct *p) +{ + struct aio_poll_table *pt = container_of(p, struct aio_poll_table, pt); + + /* multiple wait queues per file are not supported */ + if (unlikely(pt->queued)) { + pt->error = -EINVAL; + return; + } + + pt->queued = true; + pt->error = 0; + pt->iocb->poll.head = head; + add_wait_queue(head, &pt->iocb->poll.wait); +} + +static int aio_poll(struct aio_kiocb *aiocb, const struct iocb *iocb) +{ + struct kioctx *ctx = aiocb->ki_ctx; + struct poll_iocb *req = &aiocb->poll; + struct aio_poll_table apt; + bool cancel = false; + __poll_t mask; + + /* reject any unknown events outside the normal event mask. */ + if ((u16)iocb->aio_buf != iocb->aio_buf) + return -EINVAL; + /* reject fields that are not defined for poll */ + if (iocb->aio_offset || iocb->aio_nbytes || iocb->aio_rw_flags) + return -EINVAL; + + INIT_WORK(&req->work, aio_poll_complete_work); + req->events = demangle_poll(iocb->aio_buf) | EPOLLERR | EPOLLHUP; + + req->head = NULL; + req->cancelled = false; + req->work_scheduled = false; + req->work_need_resched = false; + + apt.pt._qproc = aio_poll_queue_proc; + apt.pt._key = req->events; + apt.iocb = aiocb; + apt.queued = false; + apt.error = -EINVAL; /* same as no support for IOCB_CMD_POLL */ + + /* initialized the list so that we can do list_empty checks */ + INIT_LIST_HEAD(&req->wait.entry); + init_waitqueue_func_entry(&req->wait, aio_poll_wake); + + mask = vfs_poll(req->file, &apt.pt) & req->events; + spin_lock_irq(&ctx->ctx_lock); + if (likely(apt.queued)) { + bool on_queue = poll_iocb_lock_wq(req); + + if (!on_queue || req->work_scheduled) { + /* + * aio_poll_wake() already either scheduled the async + * completion work, or completed the request inline. + */ + if (apt.error) /* unsupported case: multiple queues */ + cancel = true; + apt.error = 0; + mask = 0; + } + if (mask || apt.error) { + /* Steal to complete synchronously. */ + list_del_init(&req->wait.entry); + } else if (cancel) { + /* Cancel if possible (may be too late though). */ + WRITE_ONCE(req->cancelled, true); + } else if (on_queue) { + /* + * Actually waiting for an event, so add the request to + * active_reqs so that it can be cancelled if needed. + */ + list_add_tail(&aiocb->ki_list, &ctx->active_reqs); + aiocb->ki_cancel = aio_poll_cancel; + } + if (on_queue) + poll_iocb_unlock_wq(req); + } + if (mask) { /* no async, we'd stolen it */ + aiocb->ki_res.res = mangle_poll(mask); + apt.error = 0; + } + spin_unlock_irq(&ctx->ctx_lock); + if (mask) + iocb_put(aiocb); + return apt.error; +} + +static int __io_submit_one(struct kioctx *ctx, const struct iocb *iocb, + struct iocb __user *user_iocb, struct aio_kiocb *req, + bool compat) +{ + req->ki_filp = fget(iocb->aio_fildes); + if (unlikely(!req->ki_filp)) + return -EBADF; if (iocb->aio_flags & IOCB_FLAG_RESFD) { + struct eventfd_ctx *eventfd; /* * If the IOCB_FLAG_RESFD flag of aio_flags is set, get an * instance of the file* now. The file descriptor must be * an eventfd() fd, and will be signaled for each completed * event using the eventfd_signal() function. */ - req->ki_eventfd = eventfd_ctx_fdget((int) iocb->aio_resfd); - if (IS_ERR(req->ki_eventfd)) { - ret = PTR_ERR(req->ki_eventfd); - req->ki_eventfd = NULL; - goto out_put_req; - } - - req->common.ki_flags |= IOCB_EVENTFD; - } - - ret = kiocb_set_rw_flags(&req->common, iocb->aio_rw_flags); - if (unlikely(ret)) { - pr_debug("EINVAL: aio_rw_flags\n"); - goto out_put_req; - } + eventfd = eventfd_ctx_fdget(iocb->aio_resfd); + if (IS_ERR(eventfd)) + return PTR_ERR(eventfd); - if ((req->common.ki_flags & IOCB_NOWAIT) && - !(req->common.ki_flags & IOCB_DIRECT)) { - ret = -EOPNOTSUPP; - goto out_put_req; + req->ki_eventfd = eventfd; } - ret = put_user(KIOCB_KEY, &user_iocb->aio_key); - if (unlikely(ret)) { + if (unlikely(put_user(KIOCB_KEY, &user_iocb->aio_key))) { pr_debug("EFAULT: aio_key\n"); - goto out_put_req; + return -EFAULT; } - req->ki_user_iocb = user_iocb; - req->ki_user_data = iocb->aio_data; + req->ki_res.obj = (u64)(unsigned long)user_iocb; + req->ki_res.data = iocb->aio_data; + req->ki_res.res = 0; + req->ki_res.res2 = 0; - get_file(file); switch (iocb->aio_lio_opcode) { case IOCB_CMD_PREAD: - ret = aio_read(&req->common, iocb, false, compat); - break; + return aio_read(&req->rw, iocb, false, compat); case IOCB_CMD_PWRITE: - ret = aio_write(&req->common, iocb, false, compat); - break; + return aio_write(&req->rw, iocb, false, compat); case IOCB_CMD_PREADV: - ret = aio_read(&req->common, iocb, true, compat); - break; + return aio_read(&req->rw, iocb, true, compat); case IOCB_CMD_PWRITEV: - ret = aio_write(&req->common, iocb, true, compat); - break; + return aio_write(&req->rw, iocb, true, compat); + case IOCB_CMD_FSYNC: + return aio_fsync(&req->fsync, iocb, false); + case IOCB_CMD_FDSYNC: + return aio_fsync(&req->fsync, iocb, true); + case IOCB_CMD_POLL: + return aio_poll(req, iocb); default: pr_debug("invalid aio operation %d\n", iocb->aio_lio_opcode); - ret = -EINVAL; - break; + return -EINVAL; } - fput(file); - - if (ret && ret != -EIOCBQUEUED) - goto out_put_req; - return 0; -out_put_req: - put_reqs_available(ctx, 1); - percpu_ref_put(&ctx->reqs); - kiocb_free(req); - return ret; } -static long do_io_submit(aio_context_t ctx_id, long nr, - struct iocb __user *__user *iocbpp, bool compat) +static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, + bool compat) { - struct kioctx *ctx; - long ret = 0; - int i = 0; - struct blk_plug plug; - - if (unlikely(nr < 0)) - return -EINVAL; - - if (unlikely(nr > LONG_MAX/sizeof(*iocbpp))) - nr = LONG_MAX/sizeof(*iocbpp); + struct aio_kiocb *req; + struct iocb iocb; + int err; - if (unlikely(!access_ok(VERIFY_READ, iocbpp, (nr*sizeof(*iocbpp))))) + if (unlikely(copy_from_user(&iocb, user_iocb, sizeof(iocb)))) return -EFAULT; - ctx = lookup_ioctx(ctx_id); - if (unlikely(!ctx)) { - pr_debug("EINVAL: invalid context id\n"); + /* enforce forwards compatibility on users */ + if (unlikely(iocb.aio_reserved2)) { + pr_debug("EINVAL: reserve field set\n"); return -EINVAL; } - blk_start_plug(&plug); + /* prevent overflows */ + if (unlikely( + (iocb.aio_buf != (unsigned long)iocb.aio_buf) || + (iocb.aio_nbytes != (size_t)iocb.aio_nbytes) || + ((ssize_t)iocb.aio_nbytes < 0) + )) { + pr_debug("EINVAL: overflow check\n"); + return -EINVAL; + } - /* - * AKPM: should this return a partial result if some of the IOs were - * successfully submitted? - */ - for (i=0; i<nr; i++) { - struct iocb __user *user_iocb; - struct iocb tmp; + req = aio_get_req(ctx); + if (unlikely(!req)) + return -EAGAIN; - if (unlikely(__get_user(user_iocb, iocbpp + i))) { - ret = -EFAULT; - break; - } + err = __io_submit_one(ctx, &iocb, user_iocb, req, compat); - if (unlikely(copy_from_user(&tmp, user_iocb, sizeof(tmp)))) { - ret = -EFAULT; - break; - } + /* Done with the synchronous reference */ + iocb_put(req); - ret = io_submit_one(ctx, user_iocb, &tmp, compat); - if (ret) - break; + /* + * If err is 0, we'd either done aio_complete() ourselves or have + * arranged for that to be done asynchronously. Anything non-zero + * means that we need to destroy req ourselves. + */ + if (unlikely(err)) { + iocb_destroy(req); + put_reqs_available(ctx, 1); } - blk_finish_plug(&plug); - - percpu_ref_put(&ctx->users); - return i ? i : ret; + return err; } /* sys_io_submit: @@ -1707,67 +2082,86 @@ static long do_io_submit(aio_context_t ctx_id, long nr, SYSCALL_DEFINE3(io_submit, aio_context_t, ctx_id, long, nr, struct iocb __user * __user *, iocbpp) { - return do_io_submit(ctx_id, nr, iocbpp, 0); -} + struct kioctx *ctx; + long ret = 0; + int i = 0; + struct blk_plug plug; -#ifdef CONFIG_COMPAT -static inline long -copy_iocb(long nr, u32 __user *ptr32, struct iocb __user * __user *ptr64) -{ - compat_uptr_t uptr; - int i; + if (unlikely(nr < 0)) + return -EINVAL; - for (i = 0; i < nr; ++i) { - if (get_user(uptr, ptr32 + i)) - return -EFAULT; - if (put_user(compat_ptr(uptr), ptr64 + i)) - return -EFAULT; + ctx = lookup_ioctx(ctx_id); + if (unlikely(!ctx)) { + pr_debug("EINVAL: invalid context id\n"); + return -EINVAL; } - return 0; -} -#define MAX_AIO_SUBMITS (PAGE_SIZE/sizeof(struct iocb *)) + if (nr > ctx->nr_events) + nr = ctx->nr_events; + + if (nr > AIO_PLUG_THRESHOLD) + blk_start_plug(&plug); + for (i = 0; i < nr; i++) { + struct iocb __user *user_iocb; + + if (unlikely(get_user(user_iocb, iocbpp + i))) { + ret = -EFAULT; + break; + } + ret = io_submit_one(ctx, user_iocb, false); + if (ret) + break; + } + if (nr > AIO_PLUG_THRESHOLD) + blk_finish_plug(&plug); + + percpu_ref_put(&ctx->users); + return i ? i : ret; +} + +#ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE3(io_submit, compat_aio_context_t, ctx_id, - int, nr, u32 __user *, iocb) + int, nr, compat_uptr_t __user *, iocbpp) { - struct iocb __user * __user *iocb64; - long ret; + struct kioctx *ctx; + long ret = 0; + int i = 0; + struct blk_plug plug; if (unlikely(nr < 0)) return -EINVAL; - if (nr > MAX_AIO_SUBMITS) - nr = MAX_AIO_SUBMITS; - - iocb64 = compat_alloc_user_space(nr * sizeof(*iocb64)); - ret = copy_iocb(nr, iocb, iocb64); - if (!ret) - ret = do_io_submit(ctx_id, nr, iocb64, 1); - return ret; -} -#endif + ctx = lookup_ioctx(ctx_id); + if (unlikely(!ctx)) { + pr_debug("EINVAL: invalid context id\n"); + return -EINVAL; + } -/* lookup_kiocb - * Finds a given iocb for cancellation. - */ -static struct aio_kiocb * -lookup_kiocb(struct kioctx *ctx, struct iocb __user *iocb, u32 key) -{ - struct aio_kiocb *kiocb; + if (nr > ctx->nr_events) + nr = ctx->nr_events; - assert_spin_locked(&ctx->ctx_lock); + if (nr > AIO_PLUG_THRESHOLD) + blk_start_plug(&plug); + for (i = 0; i < nr; i++) { + compat_uptr_t user_iocb; - if (key != KIOCB_KEY) - return NULL; + if (unlikely(get_user(user_iocb, iocbpp + i))) { + ret = -EFAULT; + break; + } - /* TODO: use a hash or array, this sucks. */ - list_for_each_entry(kiocb, &ctx->active_reqs, ki_list) { - if (kiocb->ki_user_iocb == iocb) - return kiocb; + ret = io_submit_one(ctx, compat_ptr(user_iocb), true); + if (ret) + break; } - return NULL; + if (nr > AIO_PLUG_THRESHOLD) + blk_finish_plug(&plug); + + percpu_ref_put(&ctx->users); + return i ? i : ret; } +#endif /* sys_io_cancel: * Attempts to cancel an iocb previously passed to io_submit. If @@ -1784,25 +2178,27 @@ SYSCALL_DEFINE3(io_cancel, aio_context_t, ctx_id, struct iocb __user *, iocb, { struct kioctx *ctx; struct aio_kiocb *kiocb; + int ret = -EINVAL; u32 key; - int ret; + u64 obj = (u64)(unsigned long)iocb; - ret = get_user(key, &iocb->aio_key); - if (unlikely(ret)) + if (unlikely(get_user(key, &iocb->aio_key))) return -EFAULT; + if (unlikely(key != KIOCB_KEY)) + return -EINVAL; ctx = lookup_ioctx(ctx_id); if (unlikely(!ctx)) return -EINVAL; spin_lock_irq(&ctx->ctx_lock); - - kiocb = lookup_kiocb(ctx, iocb, key); - if (kiocb) - ret = kiocb_cancel(kiocb); - else - ret = -EINVAL; - + list_for_each_entry(kiocb, &ctx->active_reqs, ki_list) { + if (kiocb->ki_res.obj == obj) { + ret = kiocb->ki_cancel(&kiocb->rw); + list_del_init(&kiocb->ki_list); + break; + } + } spin_unlock_irq(&ctx->ctx_lock); if (!ret) { @@ -1819,6 +2215,25 @@ SYSCALL_DEFINE3(io_cancel, aio_context_t, ctx_id, struct iocb __user *, iocb, return ret; } +static long do_io_getevents(aio_context_t ctx_id, + long min_nr, + long nr, + struct io_event __user *events, + struct timespec64 *ts) +{ + ktime_t until = ts ? timespec64_to_ktime(*ts) : KTIME_MAX; + struct kioctx *ioctx = lookup_ioctx(ctx_id); + long ret = -EINVAL; + + if (likely(ioctx)) { + if (likely(min_nr <= nr && min_nr >= 0)) + ret = read_events(ioctx, min_nr, nr, events, until); + percpu_ref_put(&ioctx->users); + } + + return ret; +} + /* io_getevents: * Attempts to read at least min_nr events and up to nr events from * the completion queue for the aio_context specified by ctx_id. If @@ -1831,41 +2246,200 @@ SYSCALL_DEFINE3(io_cancel, aio_context_t, ctx_id, struct iocb __user *, iocb, * specifies an infinite timeout. Note that the timeout pointed to by * timeout is relative. Will fail with -ENOSYS if not implemented. */ +#ifdef CONFIG_64BIT + SYSCALL_DEFINE5(io_getevents, aio_context_t, ctx_id, long, min_nr, long, nr, struct io_event __user *, events, - struct timespec __user *, timeout) + struct __kernel_timespec __user *, timeout) { - struct kioctx *ioctx = lookup_ioctx(ctx_id); - long ret = -EINVAL; + struct timespec64 ts; + int ret; - if (likely(ioctx)) { - if (likely(min_nr <= nr && min_nr >= 0)) - ret = read_events(ioctx, min_nr, nr, events, timeout); - percpu_ref_put(&ioctx->users); - } + if (timeout && unlikely(get_timespec64(&ts, timeout))) + return -EFAULT; + + ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &ts : NULL); + if (!ret && signal_pending(current)) + ret = -EINTR; + return ret; +} + +#endif + +struct __aio_sigset { + const sigset_t __user *sigmask; + size_t sigsetsize; +}; + +SYSCALL_DEFINE6(io_pgetevents, + aio_context_t, ctx_id, + long, min_nr, + long, nr, + struct io_event __user *, events, + struct __kernel_timespec __user *, timeout, + const struct __aio_sigset __user *, usig) +{ + struct __aio_sigset ksig = { NULL, }; + struct timespec64 ts; + bool interrupted; + int ret; + + if (timeout && unlikely(get_timespec64(&ts, timeout))) + return -EFAULT; + + if (usig && copy_from_user(&ksig, usig, sizeof(ksig))) + return -EFAULT; + + ret = set_user_sigmask(ksig.sigmask, ksig.sigsetsize); + if (ret) + return ret; + + ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &ts : NULL); + + interrupted = signal_pending(current); + restore_saved_sigmask_unless(interrupted); + if (interrupted && !ret) + ret = -ERESTARTNOHAND; + + return ret; +} + +#if defined(CONFIG_COMPAT_32BIT_TIME) && !defined(CONFIG_64BIT) + +SYSCALL_DEFINE6(io_pgetevents_time32, + aio_context_t, ctx_id, + long, min_nr, + long, nr, + struct io_event __user *, events, + struct old_timespec32 __user *, timeout, + const struct __aio_sigset __user *, usig) +{ + struct __aio_sigset ksig = { NULL, }; + struct timespec64 ts; + bool interrupted; + int ret; + + if (timeout && unlikely(get_old_timespec32(&ts, timeout))) + return -EFAULT; + + if (usig && copy_from_user(&ksig, usig, sizeof(ksig))) + return -EFAULT; + + + ret = set_user_sigmask(ksig.sigmask, ksig.sigsetsize); + if (ret) + return ret; + + ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &ts : NULL); + + interrupted = signal_pending(current); + restore_saved_sigmask_unless(interrupted); + if (interrupted && !ret) + ret = -ERESTARTNOHAND; + + return ret; +} + +#endif + +#if defined(CONFIG_COMPAT_32BIT_TIME) + +SYSCALL_DEFINE5(io_getevents_time32, __u32, ctx_id, + __s32, min_nr, + __s32, nr, + struct io_event __user *, events, + struct old_timespec32 __user *, timeout) +{ + struct timespec64 t; + int ret; + + if (timeout && get_old_timespec32(&t, timeout)) + return -EFAULT; + + ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &t : NULL); + if (!ret && signal_pending(current)) + ret = -EINTR; return ret; } +#endif + #ifdef CONFIG_COMPAT -COMPAT_SYSCALL_DEFINE5(io_getevents, compat_aio_context_t, ctx_id, - compat_long_t, min_nr, - compat_long_t, nr, - struct io_event __user *, events, - struct compat_timespec __user *, timeout) -{ - struct timespec t; - struct timespec __user *ut = NULL; - - if (timeout) { - if (compat_get_timespec(&t, timeout)) - return -EFAULT; - - ut = compat_alloc_user_space(sizeof(*ut)); - if (copy_to_user(ut, &t, sizeof(t))) - return -EFAULT; - } - return sys_io_getevents(ctx_id, min_nr, nr, events, ut); + +struct __compat_aio_sigset { + compat_uptr_t sigmask; + compat_size_t sigsetsize; +}; + +#if defined(CONFIG_COMPAT_32BIT_TIME) + +COMPAT_SYSCALL_DEFINE6(io_pgetevents, + compat_aio_context_t, ctx_id, + compat_long_t, min_nr, + compat_long_t, nr, + struct io_event __user *, events, + struct old_timespec32 __user *, timeout, + const struct __compat_aio_sigset __user *, usig) +{ + struct __compat_aio_sigset ksig = { 0, }; + struct timespec64 t; + bool interrupted; + int ret; + + if (timeout && get_old_timespec32(&t, timeout)) + return -EFAULT; + + if (usig && copy_from_user(&ksig, usig, sizeof(ksig))) + return -EFAULT; + + ret = set_compat_user_sigmask(compat_ptr(ksig.sigmask), ksig.sigsetsize); + if (ret) + return ret; + + ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &t : NULL); + + interrupted = signal_pending(current); + restore_saved_sigmask_unless(interrupted); + if (interrupted && !ret) + ret = -ERESTARTNOHAND; + + return ret; +} + +#endif + +COMPAT_SYSCALL_DEFINE6(io_pgetevents_time64, + compat_aio_context_t, ctx_id, + compat_long_t, min_nr, + compat_long_t, nr, + struct io_event __user *, events, + struct __kernel_timespec __user *, timeout, + const struct __compat_aio_sigset __user *, usig) +{ + struct __compat_aio_sigset ksig = { 0, }; + struct timespec64 t; + bool interrupted; + int ret; + + if (timeout && get_timespec64(&t, timeout)) + return -EFAULT; + + if (usig && copy_from_user(&ksig, usig, sizeof(ksig))) + return -EFAULT; + + ret = set_compat_user_sigmask(compat_ptr(ksig.sigmask), ksig.sigsetsize); + if (ret) + return ret; + + ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &t : NULL); + + interrupted = signal_pending(current); + restore_saved_sigmask_unless(interrupted); + if (interrupted && !ret) + ret = -ERESTARTNOHAND; + + return ret; } #endif |
