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io_uring: move io_uring_task (tctx) helpers into its own file

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Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe
2022-05-25 11:01:04 -06:00
parent a4ad4f748e
commit c9f06aa7de
5 changed files with 396 additions and 365 deletions
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2
io_uring/Makefile
View File

@@ -6,5 +6,5 @@ obj-$(CONFIG_IO_URING) += io_uring.o xattr.o nop.o fs.o splice.o \
sync.o advise.o filetable.o \ sync.o advise.o filetable.o \
openclose.o uring_cmd.o epoll.o \ openclose.o uring_cmd.o epoll.o \
statx.o net.o msg_ring.o timeout.o \ statx.o net.o msg_ring.o timeout.o \
sqpoll.o fdinfo.o sqpoll.o fdinfo.o tctx.o
obj-$(CONFIG_IO_WQ) += io-wq.o obj-$(CONFIG_IO_WQ) += io-wq.o

368
io_uring/io_uring.c
View File

@@ -92,6 +92,7 @@
#include "io_uring_types.h" #include "io_uring_types.h"
#include "io_uring.h" #include "io_uring.h"
#include "refs.h" #include "refs.h"
#include "tctx.h"
#include "sqpoll.h" #include "sqpoll.h"
#include "fdinfo.h" #include "fdinfo.h"
@@ -208,30 +209,6 @@ struct io_buffer {
#define BGID_ARRAY 64 #define BGID_ARRAY 64
/*
* Arbitrary limit, can be raised if need be
*/
#define IO_RINGFD_REG_MAX 16
struct io_uring_task {
/* submission side */
int cached_refs;
struct xarray xa;
struct wait_queue_head wait;
const struct io_ring_ctx *last;
struct io_wq *io_wq;
struct percpu_counter inflight;
atomic_t inflight_tracked;
atomic_t in_idle;
spinlock_t task_lock;
struct io_wq_work_list task_list;
struct io_wq_work_list prio_task_list;
struct callback_head task_work;
struct file **registered_rings;
bool task_running;
};
/* /*
* First field must be the file pointer in all the * First field must be the file pointer in all the
* iocb unions! See also 'struct kiocb' in <linux/fs.h> * iocb unions! See also 'struct kiocb' in <linux/fs.h>
@@ -311,12 +288,6 @@ enum {
IO_CHECK_CQ_DROPPED_BIT, IO_CHECK_CQ_DROPPED_BIT,
}; };
struct io_tctx_node {
struct list_head ctx_node;
struct task_struct *task;
struct io_ring_ctx *ctx;
};
struct io_defer_entry { struct io_defer_entry {
struct list_head list; struct list_head list;
struct io_kiocb *req; struct io_kiocb *req;
@@ -361,7 +332,6 @@ static const struct io_op_def io_op_defs[];
#define IO_DISARM_MASK (REQ_F_ARM_LTIMEOUT | REQ_F_LINK_TIMEOUT | REQ_F_FAIL) #define IO_DISARM_MASK (REQ_F_ARM_LTIMEOUT | REQ_F_LINK_TIMEOUT | REQ_F_FAIL)
#define IO_REQ_LINK_FLAGS (REQ_F_LINK | REQ_F_HARDLINK) #define IO_REQ_LINK_FLAGS (REQ_F_LINK | REQ_F_HARDLINK)
static void io_uring_del_tctx_node(unsigned long index);
static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx, static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
struct task_struct *task, struct task_struct *task,
bool cancel_all); bool cancel_all);
@@ -1677,7 +1647,7 @@ static void handle_tw_list(struct io_wq_work_node *node,
} while (node); } while (node);
} }
static void tctx_task_work(struct callback_head *cb) void tctx_task_work(struct callback_head *cb)
{ {
bool uring_locked = false; bool uring_locked = false;
struct io_ring_ctx *ctx = NULL; struct io_ring_ctx *ctx = NULL;
@@ -4725,7 +4695,7 @@ static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
return 0; return 0;
} }
static struct io_wq_work *io_wq_free_work(struct io_wq_work *work) struct io_wq_work *io_wq_free_work(struct io_wq_work *work)
{ {
struct io_kiocb *req = container_of(work, struct io_kiocb, work); struct io_kiocb *req = container_of(work, struct io_kiocb, work);
@@ -4733,7 +4703,7 @@ static struct io_wq_work *io_wq_free_work(struct io_wq_work *work)
return req ? &req->work : NULL; return req ? &req->work : NULL;
} }
static void io_wq_submit_work(struct io_wq_work *work) void io_wq_submit_work(struct io_wq_work *work)
{ {
struct io_kiocb *req = container_of(work, struct io_kiocb, work); struct io_kiocb *req = container_of(work, struct io_kiocb, work);
const struct io_op_def *def = &io_op_defs[req->opcode]; const struct io_op_def *def = &io_op_defs[req->opcode];
@@ -6089,97 +6059,6 @@ static int __io_sqe_files_update(struct io_ring_ctx *ctx,
return done ? done : err; return done ? done : err;
} }
static struct io_wq *io_init_wq_offload(struct io_ring_ctx *ctx,
struct task_struct *task)
{
struct io_wq_hash *hash;
struct io_wq_data data;
unsigned int concurrency;
mutex_lock(&ctx->uring_lock);
hash = ctx->hash_map;
if (!hash) {
hash = kzalloc(sizeof(*hash), GFP_KERNEL);
if (!hash) {
mutex_unlock(&ctx->uring_lock);
return ERR_PTR(-ENOMEM);
}
refcount_set(&hash->refs, 1);
init_waitqueue_head(&hash->wait);
ctx->hash_map = hash;
}
mutex_unlock(&ctx->uring_lock);
data.hash = hash;
data.task = task;
data.free_work = io_wq_free_work;
data.do_work = io_wq_submit_work;
/* Do QD, or 4 * CPUS, whatever is smallest */
concurrency = min(ctx->sq_entries, 4 * num_online_cpus());
return io_wq_create(concurrency, &data);
}
__cold int io_uring_alloc_task_context(struct task_struct *task,
struct io_ring_ctx *ctx)
{
struct io_uring_task *tctx;
int ret;
tctx = kzalloc(sizeof(*tctx), GFP_KERNEL);
if (unlikely(!tctx))
return -ENOMEM;
tctx->registered_rings = kcalloc(IO_RINGFD_REG_MAX,
sizeof(struct file *), GFP_KERNEL);
if (unlikely(!tctx->registered_rings)) {
kfree(tctx);
return -ENOMEM;
}
ret = percpu_counter_init(&tctx->inflight, 0, GFP_KERNEL);
if (unlikely(ret)) {
kfree(tctx->registered_rings);
kfree(tctx);
return ret;
}
tctx->io_wq = io_init_wq_offload(ctx, task);
if (IS_ERR(tctx->io_wq)) {
ret = PTR_ERR(tctx->io_wq);
percpu_counter_destroy(&tctx->inflight);
kfree(tctx->registered_rings);
kfree(tctx);
return ret;
}
xa_init(&tctx->xa);
init_waitqueue_head(&tctx->wait);
atomic_set(&tctx->in_idle, 0);
atomic_set(&tctx->inflight_tracked, 0);
task->io_uring = tctx;
spin_lock_init(&tctx->task_lock);
INIT_WQ_LIST(&tctx->task_list);
INIT_WQ_LIST(&tctx->prio_task_list);
init_task_work(&tctx->task_work, tctx_task_work);
return 0;
}
void __io_uring_free(struct task_struct *tsk)
{
struct io_uring_task *tctx = tsk->io_uring;
WARN_ON_ONCE(!xa_empty(&tctx->xa));
WARN_ON_ONCE(tctx->io_wq);
WARN_ON_ONCE(tctx->cached_refs);
kfree(tctx->registered_rings);
percpu_counter_destroy(&tctx->inflight);
kfree(tctx);
tsk->io_uring = NULL;
}
static inline void __io_unaccount_mem(struct user_struct *user, static inline void __io_unaccount_mem(struct user_struct *user,
unsigned long nr_pages) unsigned long nr_pages)
{ {
@@ -7179,107 +7058,6 @@ static __cold void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
} }
} }
static int __io_uring_add_tctx_node(struct io_ring_ctx *ctx)
{
struct io_uring_task *tctx = current->io_uring;
struct io_tctx_node *node;
int ret;
if (unlikely(!tctx)) {
ret = io_uring_alloc_task_context(current, ctx);
if (unlikely(ret))
return ret;
tctx = current->io_uring;
if (ctx->iowq_limits_set) {
unsigned int limits[2] = { ctx->iowq_limits[0],
ctx->iowq_limits[1], };
ret = io_wq_max_workers(tctx->io_wq, limits);
if (ret)
return ret;
}
}
if (!xa_load(&tctx->xa, (unsigned long)ctx)) {
node = kmalloc(sizeof(*node), GFP_KERNEL);
if (!node)
return -ENOMEM;
node->ctx = ctx;
node->task = current;
ret = xa_err(xa_store(&tctx->xa, (unsigned long)ctx,
node, GFP_KERNEL));
if (ret) {
kfree(node);
return ret;
}
mutex_lock(&ctx->uring_lock);
list_add(&node->ctx_node, &ctx->tctx_list);
mutex_unlock(&ctx->uring_lock);
}
tctx->last = ctx;
return 0;
}
/*
* Note that this task has used io_uring. We use it for cancelation purposes.
*/
static inline int io_uring_add_tctx_node(struct io_ring_ctx *ctx)
{
struct io_uring_task *tctx = current->io_uring;
if (likely(tctx && tctx->last == ctx))
return 0;
return __io_uring_add_tctx_node(ctx);
}
/*
* Remove this io_uring_file -> task mapping.
*/
static __cold void io_uring_del_tctx_node(unsigned long index)
{
struct io_uring_task *tctx = current->io_uring;
struct io_tctx_node *node;
if (!tctx)
return;
node = xa_erase(&tctx->xa, index);
if (!node)
return;
WARN_ON_ONCE(current != node->task);
WARN_ON_ONCE(list_empty(&node->ctx_node));
mutex_lock(&node->ctx->uring_lock);
list_del(&node->ctx_node);
mutex_unlock(&node->ctx->uring_lock);
if (tctx->last == node->ctx)
tctx->last = NULL;
kfree(node);
}
static __cold void io_uring_clean_tctx(struct io_uring_task *tctx)
{
struct io_wq *wq = tctx->io_wq;
struct io_tctx_node *node;
unsigned long index;
xa_for_each(&tctx->xa, index, node) {
io_uring_del_tctx_node(index);
cond_resched();
}
if (wq) {
/*
* Must be after io_uring_del_tctx_node() (removes nodes under
* uring_lock) to avoid race with io_uring_try_cancel_iowq().
*/
io_wq_put_and_exit(wq);
tctx->io_wq = NULL;
}
}
static s64 tctx_inflight(struct io_uring_task *tctx, bool tracked) static s64 tctx_inflight(struct io_uring_task *tctx, bool tracked)
{ {
if (tracked) if (tracked)
@@ -7361,144 +7139,6 @@ void __io_uring_cancel(bool cancel_all)
io_uring_cancel_generic(cancel_all, NULL); io_uring_cancel_generic(cancel_all, NULL);
} }
void io_uring_unreg_ringfd(void)
{
struct io_uring_task *tctx = current->io_uring;
int i;
for (i = 0; i < IO_RINGFD_REG_MAX; i++) {
if (tctx->registered_rings[i]) {
fput(tctx->registered_rings[i]);
tctx->registered_rings[i] = NULL;
}
}
}
static int io_ring_add_registered_fd(struct io_uring_task *tctx, int fd,
int start, int end)
{
struct file *file;
int offset;
for (offset = start; offset < end; offset++) {
offset = array_index_nospec(offset, IO_RINGFD_REG_MAX);
if (tctx->registered_rings[offset])
continue;
file = fget(fd);
if (!file) {
return -EBADF;
} else if (!io_is_uring_fops(file)) {
fput(file);
return -EOPNOTSUPP;
}
tctx->registered_rings[offset] = file;
return offset;
}
return -EBUSY;
}
/*
* Register a ring fd to avoid fdget/fdput for each io_uring_enter()
* invocation. User passes in an array of struct io_uring_rsrc_update
* with ->data set to the ring_fd, and ->offset given for the desired
* index. If no index is desired, application may set ->offset == -1U
* and we'll find an available index. Returns number of entries
* successfully processed, or < 0 on error if none were processed.
*/
static int io_ringfd_register(struct io_ring_ctx *ctx, void __user *__arg,
unsigned nr_args)
{
struct io_uring_rsrc_update __user *arg = __arg;
struct io_uring_rsrc_update reg;
struct io_uring_task *tctx;
int ret, i;
if (!nr_args || nr_args > IO_RINGFD_REG_MAX)
return -EINVAL;
mutex_unlock(&ctx->uring_lock);
ret = io_uring_add_tctx_node(ctx);
mutex_lock(&ctx->uring_lock);
if (ret)
return ret;
tctx = current->io_uring;
for (i = 0; i < nr_args; i++) {
int start, end;
if (copy_from_user(&reg, &arg[i], sizeof(reg))) {
ret = -EFAULT;
break;
}
if (reg.resv) {
ret = -EINVAL;
break;
}
if (reg.offset == -1U) {
start = 0;
end = IO_RINGFD_REG_MAX;
} else {
if (reg.offset >= IO_RINGFD_REG_MAX) {
ret = -EINVAL;
break;
}
start = reg.offset;
end = start + 1;
}
ret = io_ring_add_registered_fd(tctx, reg.data, start, end);
if (ret < 0)
break;
reg.offset = ret;
if (copy_to_user(&arg[i], &reg, sizeof(reg))) {
fput(tctx->registered_rings[reg.offset]);
tctx->registered_rings[reg.offset] = NULL;
ret = -EFAULT;
break;
}
}
return i ? i : ret;
}
static int io_ringfd_unregister(struct io_ring_ctx *ctx, void __user *__arg,
unsigned nr_args)
{
struct io_uring_rsrc_update __user *arg = __arg;
struct io_uring_task *tctx = current->io_uring;
struct io_uring_rsrc_update reg;
int ret = 0, i;
if (!nr_args || nr_args > IO_RINGFD_REG_MAX)
return -EINVAL;
if (!tctx)
return 0;
for (i = 0; i < nr_args; i++) {
if (copy_from_user(&reg, &arg[i], sizeof(reg))) {
ret = -EFAULT;
break;
}
if (reg.resv || reg.data || reg.offset >= IO_RINGFD_REG_MAX) {
ret = -EINVAL;
break;
}
reg.offset = array_index_nospec(reg.offset, IO_RINGFD_REG_MAX);
if (tctx->registered_rings[reg.offset]) {
fput(tctx->registered_rings[reg.offset]);
tctx->registered_rings[reg.offset] = NULL;
}
}
return i ? i : ret;
}
static void *io_uring_validate_mmap_request(struct file *file, static void *io_uring_validate_mmap_request(struct file *file,
loff_t pgoff, size_t sz) loff_t pgoff, size_t sz)
{ {

4
io_uring/io_uring.h
View File

@@ -128,6 +128,7 @@ void io_req_task_work_add(struct io_kiocb *req);
void io_req_tw_post_queue(struct io_kiocb *req, s32 res, u32 cflags); void io_req_tw_post_queue(struct io_kiocb *req, s32 res, u32 cflags);
void io_req_task_complete(struct io_kiocb *req, bool *locked); void io_req_task_complete(struct io_kiocb *req, bool *locked);
void io_req_task_queue_fail(struct io_kiocb *req, int ret); void io_req_task_queue_fail(struct io_kiocb *req, int ret);
void tctx_task_work(struct callback_head *cb);
int io_try_cancel(struct io_kiocb *req, struct io_cancel_data *cd); int io_try_cancel(struct io_kiocb *req, struct io_cancel_data *cd);
__cold void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd); __cold void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd);
int io_uring_alloc_task_context(struct task_struct *task, int io_uring_alloc_task_context(struct task_struct *task,
@@ -136,6 +137,9 @@ int io_uring_alloc_task_context(struct task_struct *task,
int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr); int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr);
int io_do_iopoll(struct io_ring_ctx *ctx, bool force_nonspin); int io_do_iopoll(struct io_ring_ctx *ctx, bool force_nonspin);
struct io_wq_work *io_wq_free_work(struct io_wq_work *work);
void io_wq_submit_work(struct io_wq_work *work);
void io_free_req(struct io_kiocb *req); void io_free_req(struct io_kiocb *req);
void io_queue_next(struct io_kiocb *req); void io_queue_next(struct io_kiocb *req);

332
io_uring/tctx.c Normal file
View File

@@ -0,0 +1,332 @@
// SPDX-License-Identifier: GPL-2.0
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/file.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/nospec.h>
#include <linux/io_uring.h>
#include <uapi/linux/io_uring.h>
#include "io_uring_types.h"
#include "io_uring.h"
#include "tctx.h"
static struct io_wq *io_init_wq_offload(struct io_ring_ctx *ctx,
struct task_struct *task)
{
struct io_wq_hash *hash;
struct io_wq_data data;
unsigned int concurrency;
mutex_lock(&ctx->uring_lock);
hash = ctx->hash_map;
if (!hash) {
hash = kzalloc(sizeof(*hash), GFP_KERNEL);
if (!hash) {
mutex_unlock(&ctx->uring_lock);
return ERR_PTR(-ENOMEM);
}
refcount_set(&hash->refs, 1);
init_waitqueue_head(&hash->wait);
ctx->hash_map = hash;
}
mutex_unlock(&ctx->uring_lock);
data.hash = hash;
data.task = task;
data.free_work = io_wq_free_work;
data.do_work = io_wq_submit_work;
/* Do QD, or 4 * CPUS, whatever is smallest */
concurrency = min(ctx->sq_entries, 4 * num_online_cpus());
return io_wq_create(concurrency, &data);
}
void __io_uring_free(struct task_struct *tsk)
{
struct io_uring_task *tctx = tsk->io_uring;
WARN_ON_ONCE(!xa_empty(&tctx->xa));
WARN_ON_ONCE(tctx->io_wq);
WARN_ON_ONCE(tctx->cached_refs);
kfree(tctx->registered_rings);
percpu_counter_destroy(&tctx->inflight);
kfree(tctx);
tsk->io_uring = NULL;
}
__cold int io_uring_alloc_task_context(struct task_struct *task,
struct io_ring_ctx *ctx)
{
struct io_uring_task *tctx;
int ret;
tctx = kzalloc(sizeof(*tctx), GFP_KERNEL);
if (unlikely(!tctx))
return -ENOMEM;
tctx->registered_rings = kcalloc(IO_RINGFD_REG_MAX,
sizeof(struct file *), GFP_KERNEL);
if (unlikely(!tctx->registered_rings)) {
kfree(tctx);
return -ENOMEM;
}
ret = percpu_counter_init(&tctx->inflight, 0, GFP_KERNEL);
if (unlikely(ret)) {
kfree(tctx->registered_rings);
kfree(tctx);
return ret;
}
tctx->io_wq = io_init_wq_offload(ctx, task);
if (IS_ERR(tctx->io_wq)) {
ret = PTR_ERR(tctx->io_wq);
percpu_counter_destroy(&tctx->inflight);
kfree(tctx->registered_rings);
kfree(tctx);
return ret;
}
xa_init(&tctx->xa);
init_waitqueue_head(&tctx->wait);
atomic_set(&tctx->in_idle, 0);
atomic_set(&tctx->inflight_tracked, 0);
task->io_uring = tctx;
spin_lock_init(&tctx->task_lock);
INIT_WQ_LIST(&tctx->task_list);
INIT_WQ_LIST(&tctx->prio_task_list);
init_task_work(&tctx->task_work, tctx_task_work);
return 0;
}
int __io_uring_add_tctx_node(struct io_ring_ctx *ctx)
{
struct io_uring_task *tctx = current->io_uring;
struct io_tctx_node *node;
int ret;
if (unlikely(!tctx)) {
ret = io_uring_alloc_task_context(current, ctx);
if (unlikely(ret))
return ret;
tctx = current->io_uring;
if (ctx->iowq_limits_set) {
unsigned int limits[2] = { ctx->iowq_limits[0],
ctx->iowq_limits[1], };
ret = io_wq_max_workers(tctx->io_wq, limits);
if (ret)
return ret;
}
}
if (!xa_load(&tctx->xa, (unsigned long)ctx)) {
node = kmalloc(sizeof(*node), GFP_KERNEL);
if (!node)
return -ENOMEM;
node->ctx = ctx;
node->task = current;
ret = xa_err(xa_store(&tctx->xa, (unsigned long)ctx,
node, GFP_KERNEL));
if (ret) {
kfree(node);
return ret;
}
mutex_lock(&ctx->uring_lock);
list_add(&node->ctx_node, &ctx->tctx_list);
mutex_unlock(&ctx->uring_lock);
}
tctx->last = ctx;
return 0;
}
/*
* Remove this io_uring_file -> task mapping.
*/
__cold void io_uring_del_tctx_node(unsigned long index)
{
struct io_uring_task *tctx = current->io_uring;
struct io_tctx_node *node;
if (!tctx)
return;
node = xa_erase(&tctx->xa, index);
if (!node)
return;
WARN_ON_ONCE(current != node->task);
WARN_ON_ONCE(list_empty(&node->ctx_node));
mutex_lock(&node->ctx->uring_lock);
list_del(&node->ctx_node);
mutex_unlock(&node->ctx->uring_lock);
if (tctx->last == node->ctx)
tctx->last = NULL;
kfree(node);
}
__cold void io_uring_clean_tctx(struct io_uring_task *tctx)
{
struct io_wq *wq = tctx->io_wq;
struct io_tctx_node *node;
unsigned long index;
xa_for_each(&tctx->xa, index, node) {
io_uring_del_tctx_node(index);
cond_resched();
}
if (wq) {
/*
* Must be after io_uring_del_tctx_node() (removes nodes under
* uring_lock) to avoid race with io_uring_try_cancel_iowq().
*/
io_wq_put_and_exit(wq);
tctx->io_wq = NULL;
}
}
void io_uring_unreg_ringfd(void)
{
struct io_uring_task *tctx = current->io_uring;
int i;
for (i = 0; i < IO_RINGFD_REG_MAX; i++) {
if (tctx->registered_rings[i]) {
fput(tctx->registered_rings[i]);
tctx->registered_rings[i] = NULL;
}
}
}
static int io_ring_add_registered_fd(struct io_uring_task *tctx, int fd,
int start, int end)
{
struct file *file;
int offset;
for (offset = start; offset < end; offset++) {
offset = array_index_nospec(offset, IO_RINGFD_REG_MAX);
if (tctx->registered_rings[offset])
continue;
file = fget(fd);
if (!file) {
return -EBADF;
} else if (!io_is_uring_fops(file)) {
fput(file);
return -EOPNOTSUPP;
}
tctx->registered_rings[offset] = file;
return offset;
}
return -EBUSY;
}
/*
* Register a ring fd to avoid fdget/fdput for each io_uring_enter()
* invocation. User passes in an array of struct io_uring_rsrc_update
* with ->data set to the ring_fd, and ->offset given for the desired
* index. If no index is desired, application may set ->offset == -1U
* and we'll find an available index. Returns number of entries
* successfully processed, or < 0 on error if none were processed.
*/
int io_ringfd_register(struct io_ring_ctx *ctx, void __user *__arg,
unsigned nr_args)
{
struct io_uring_rsrc_update __user *arg = __arg;
struct io_uring_rsrc_update reg;
struct io_uring_task *tctx;
int ret, i;
if (!nr_args || nr_args > IO_RINGFD_REG_MAX)
return -EINVAL;
mutex_unlock(&ctx->uring_lock);
ret = io_uring_add_tctx_node(ctx);
mutex_lock(&ctx->uring_lock);
if (ret)
return ret;
tctx = current->io_uring;
for (i = 0; i < nr_args; i++) {
int start, end;
if (copy_from_user(&reg, &arg[i], sizeof(reg))) {
ret = -EFAULT;
break;
}
if (reg.resv) {
ret = -EINVAL;
break;
}
if (reg.offset == -1U) {
start = 0;
end = IO_RINGFD_REG_MAX;
} else {
if (reg.offset >= IO_RINGFD_REG_MAX) {
ret = -EINVAL;
break;
}
start = reg.offset;
end = start + 1;
}
ret = io_ring_add_registered_fd(tctx, reg.data, start, end);
if (ret < 0)
break;
reg.offset = ret;
if (copy_to_user(&arg[i], &reg, sizeof(reg))) {
fput(tctx->registered_rings[reg.offset]);
tctx->registered_rings[reg.offset] = NULL;
ret = -EFAULT;
break;
}
}
return i ? i : ret;
}
int io_ringfd_unregister(struct io_ring_ctx *ctx, void __user *__arg,
unsigned nr_args)
{
struct io_uring_rsrc_update __user *arg = __arg;
struct io_uring_task *tctx = current->io_uring;
struct io_uring_rsrc_update reg;
int ret = 0, i;
if (!nr_args || nr_args > IO_RINGFD_REG_MAX)
return -EINVAL;
if (!tctx)
return 0;
for (i = 0; i < nr_args; i++) {
if (copy_from_user(&reg, &arg[i], sizeof(reg))) {
ret = -EFAULT;
break;
}
if (reg.resv || reg.data || reg.offset >= IO_RINGFD_REG_MAX) {
ret = -EINVAL;
break;
}
reg.offset = array_index_nospec(reg.offset, IO_RINGFD_REG_MAX);
if (tctx->registered_rings[reg.offset]) {
fput(tctx->registered_rings[reg.offset]);
tctx->registered_rings[reg.offset] = NULL;
}
}
return i ? i : ret;
}

55
io_uring/tctx.h Normal file
View File

@@ -0,0 +1,55 @@
// SPDX-License-Identifier: GPL-2.0
/*
* Arbitrary limit, can be raised if need be
*/
#define IO_RINGFD_REG_MAX 16
struct io_uring_task {
/* submission side */
int cached_refs;
struct xarray xa;
struct wait_queue_head wait;
const struct io_ring_ctx *last;
struct io_wq *io_wq;
struct percpu_counter inflight;
atomic_t inflight_tracked;
atomic_t in_idle;
spinlock_t task_lock;
struct io_wq_work_list task_list;
struct io_wq_work_list prio_task_list;
struct callback_head task_work;
struct file **registered_rings;
bool task_running;
};
struct io_tctx_node {
struct list_head ctx_node;
struct task_struct *task;
struct io_ring_ctx *ctx;
};
int io_uring_alloc_task_context(struct task_struct *task,
struct io_ring_ctx *ctx);
void io_uring_del_tctx_node(unsigned long index);
int __io_uring_add_tctx_node(struct io_ring_ctx *ctx);
void io_uring_clean_tctx(struct io_uring_task *tctx);
void io_uring_unreg_ringfd(void);
int io_ringfd_register(struct io_ring_ctx *ctx, void __user *__arg,
unsigned nr_args);
int io_ringfd_unregister(struct io_ring_ctx *ctx, void __user *__arg,
unsigned nr_args);
/*
* Note that this task has used io_uring. We use it for cancelation purposes.
*/
static inline int io_uring_add_tctx_node(struct io_ring_ctx *ctx)
{
struct io_uring_task *tctx = current->io_uring;
if (likely(tctx && tctx->last == ctx))
return 0;
return __io_uring_add_tctx_node(ctx);
}