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-rw-r--r--fs/aio.c1616
1 files changed, 1095 insertions, 521 deletions
diff --git a/fs/aio.c b/fs/aio.c
index dcad3a66748c..0a23a8c0717f 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -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