io_uring: rely solely on work flags to determine personality.

We solely rely on work->work_flags now, so use that for proper checking
and clearing/dropping of various identity items.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io-wq.c b/fs/io-wq.c
index e636898..b7d8e54 100644 (file)
--- a/fs/io-wq.c
+++ b/fs/io-wq.c
@@ -429,14 +429,10 @@ static void io_wq_switch_mm(struct io_worker *worker, struct io_wq_work *work)
                mmput(worker->mm);
                worker->mm = NULL;
        }
-       if (!work->mm)
-               return;
 
        if (mmget_not_zero(work->mm)) {
                kthread_use_mm(work->mm);
                worker->mm = work->mm;
-               /* hang on to this mm */
-               work->mm = NULL;
                return;
        }
 

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 04a4d8c..e92ed22 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -1162,19 +1162,21 @@ static void io_req_clean_work(struct io_kiocb *req)
 
        req->flags &= ~REQ_F_WORK_INITIALIZED;
 
-       if (req->work.mm) {
+       if (req->work.flags & IO_WQ_WORK_MM) {
                mmdrop(req->work.mm);
-               req->work.mm = NULL;
+               req->work.flags &= ~IO_WQ_WORK_MM;
        }
 #ifdef CONFIG_BLK_CGROUP
-       if (req->work.blkcg_css)
+       if (req->work.flags & IO_WQ_WORK_BLKCG) {
                css_put(req->work.blkcg_css);
+               req->work.flags &= ~IO_WQ_WORK_BLKCG;
+       }
 #endif
-       if (req->work.creds) {
+       if (req->work.flags & IO_WQ_WORK_CREDS) {
                put_cred(req->work.creds);
-               req->work.creds = NULL;
+               req->work.flags &= ~IO_WQ_WORK_CREDS;
        }
-       if (req->work.fs) {
+       if (req->work.flags & IO_WQ_WORK_FS) {
                struct fs_struct *fs = req->work.fs;
 
                spin_lock(&req->work.fs->lock);
@@ -1183,7 +1185,7 @@ static void io_req_clean_work(struct io_kiocb *req)
                spin_unlock(&req->work.fs->lock);
                if (fs)
                        free_fs_struct(fs);
-               req->work.fs = NULL;
+               req->work.flags &= ~IO_WQ_WORK_FS;
        }
 }
 
@@ -1201,7 +1203,7 @@ static void io_prep_async_work(struct io_kiocb *req)
                if (def->unbound_nonreg_file)
                        req->work.flags |= IO_WQ_WORK_UNBOUND;
        }
-       if (!req->work.files &&
+       if (!(req->work.flags & IO_WQ_WORK_FILES) &&
            (io_op_defs[req->opcode].work_flags & IO_WQ_WORK_FILES) &&
            !(req->flags & REQ_F_NO_FILE_TABLE)) {
                req->work.files = get_files_struct(current);
@@ -1212,13 +1214,17 @@ static void io_prep_async_work(struct io_kiocb *req)
                spin_lock_irq(&ctx->inflight_lock);
                list_add(&req->inflight_entry, &ctx->inflight_list);
                spin_unlock_irq(&ctx->inflight_lock);
+               req->work.flags |= IO_WQ_WORK_FILES;
        }
-       if (!req->work.mm && (def->work_flags & IO_WQ_WORK_MM)) {
+       if (!(req->work.flags & IO_WQ_WORK_MM) &&
+           (def->work_flags & IO_WQ_WORK_MM)) {
                mmgrab(current->mm);
                req->work.mm = current->mm;
+               req->work.flags |= IO_WQ_WORK_MM;
        }
 #ifdef CONFIG_BLK_CGROUP
-       if (!req->work.blkcg_css && (def->work_flags & IO_WQ_WORK_BLKCG)) {
+       if (!(req->work.flags & IO_WQ_WORK_BLKCG) &&
+           (def->work_flags & IO_WQ_WORK_BLKCG)) {
                rcu_read_lock();
                req->work.blkcg_css = blkcg_css();
                /*
@@ -1227,16 +1233,22 @@ static void io_prep_async_work(struct io_kiocb *req)
                 */
                if (!css_tryget_online(req->work.blkcg_css))
                        req->work.blkcg_css = NULL;
+               else
+                       req->work.flags |= IO_WQ_WORK_BLKCG;
                rcu_read_unlock();
        }
 #endif
-       if (!req->work.creds)
+       if (!(req->work.flags & IO_WQ_WORK_CREDS)) {
                req->work.creds = get_current_cred();
-       if (!req->work.fs && (def->work_flags & IO_WQ_WORK_FS)) {
+               req->work.flags |= IO_WQ_WORK_CREDS;
+       }
+       if (!(req->work.flags & IO_WQ_WORK_FS) &&
+           (def->work_flags & IO_WQ_WORK_FS)) {
                spin_lock(&current->fs->lock);
                if (!current->fs->in_exec) {
                        req->work.fs = current->fs;
                        req->work.fs->users++;
+                       req->work.flags |= IO_WQ_WORK_FS;
                } else {
                        req->work.flags |= IO_WQ_WORK_CANCEL;
                }
@@ -1246,8 +1258,6 @@ static void io_prep_async_work(struct io_kiocb *req)
                req->work.fsize = rlimit(RLIMIT_FSIZE);
        else
                req->work.fsize = RLIM_INFINITY;
-
-       req->work.flags |= def->work_flags;
 }
 
 static void io_prep_async_link(struct io_kiocb *req)
@@ -1437,7 +1447,8 @@ static inline bool io_match_files(struct io_kiocb *req,
 {
        if (!files)
                return true;
-       if (req->flags & REQ_F_WORK_INITIALIZED)
+       if ((req->flags & REQ_F_WORK_INITIALIZED) &&
+           (req->work.flags & IO_WQ_WORK_FILES))
                return req->work.files == files;
        return false;
 }
@@ -5694,7 +5705,7 @@ static void io_req_drop_files(struct io_kiocb *req)
        req->flags &= ~REQ_F_INFLIGHT;
        put_files_struct(req->work.files);
        put_nsproxy(req->work.nsproxy);
-       req->work.files = NULL;
+       req->work.flags &= ~IO_WQ_WORK_FILES;
 }
 
 static void __io_clean_op(struct io_kiocb *req)
@@ -6060,6 +6071,7 @@ again:
                        old_creds = NULL; /* restored original creds */
                else
                        old_creds = override_creds(req->work.creds);
+               req->work.flags |= IO_WQ_WORK_CREDS;
        }
 
        ret = io_issue_sqe(req, true, cs);
@@ -6367,6 +6379,7 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
                if (unlikely(!req->work.creds))
                        return -EINVAL;
                get_cred(req->work.creds);
+               req->work.flags |= IO_WQ_WORK_CREDS;
        }
 
        /* same numerical values with corresponding REQ_F_*, safe to copy */
@@ -8234,7 +8247,8 @@ static bool io_wq_files_match(struct io_wq_work *work, void *data)
 {
        struct files_struct *files = data;
 
-       return !files || work->files == files;
+       return !files || ((work->flags & IO_WQ_WORK_FILES) &&
+                               work->files == files);
 }
 
 /*
@@ -8389,7 +8403,8 @@ static bool io_uring_cancel_files(struct io_ring_ctx *ctx,
 
                spin_lock_irq(&ctx->inflight_lock);
                list_for_each_entry(req, &ctx->inflight_list, inflight_entry) {
-                       if (files && req->work.files != files)
+                       if (files && (req->work.flags & IO_WQ_WORK_FILES) &&
+                           req->work.files != files)
                                continue;
                        /* req is being completed, ignore */
                        if (!refcount_inc_not_zero(&req->refs))