Don't reference the kiocb structure from the common aio code, and move
any use of it into helper specific to the read/write path.  This is in
preparation for aio_poll support that wants to use the space for different
fields.

Signed-off-by: Christoph Hellwig <h...@lst.de>
Acked-by: Jeff Moyer <jmo...@redhat.com>
---
 fs/aio.c | 171 ++++++++++++++++++++++++++++++++++++---------------------------
 1 file changed, 97 insertions(+), 74 deletions(-)

diff --git a/fs/aio.c b/fs/aio.c
index 41fc8ce6bc7f..6295fc00f104 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -170,7 +170,9 @@ struct kioctx {
 #define KIOCB_CANCELLED                ((void *) (~0ULL))
 
 struct aio_kiocb {
-       struct kiocb            common;
+       union {
+               struct kiocb            rw;
+       };
 
        struct kioctx           *ki_ctx;
        kiocb_cancel_fn         *ki_cancel;
@@ -549,7 +551,7 @@ static int aio_setup_ring(struct kioctx *ctx, unsigned int 
nr_events)
 
 void kiocb_set_cancel_fn(struct kiocb *iocb, kiocb_cancel_fn *cancel)
 {
-       struct aio_kiocb *req = container_of(iocb, struct aio_kiocb, common);
+       struct aio_kiocb *req = container_of(iocb, struct aio_kiocb, rw);
        struct kioctx *ctx = req->ki_ctx;
        unsigned long flags;
 
@@ -582,7 +584,7 @@ static int kiocb_cancel(struct aio_kiocb *kiocb)
                cancel = cmpxchg(&kiocb->ki_cancel, old, KIOCB_CANCELLED);
        } while (cancel != old);
 
-       return cancel(&kiocb->common);
+       return cancel(&kiocb->rw);
 }
 
 static void free_ioctx(struct work_struct *work)
@@ -1040,15 +1042,6 @@ static inline struct aio_kiocb *aio_get_req(struct 
kioctx *ctx)
        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)
 {
        struct aio_ring __user *ring  = (void __user *)ctx_id;
@@ -1079,29 +1072,14 @@ static struct kioctx *lookup_ioctx(unsigned long ctx_id)
 /* 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, long res, long res2)
 {
-       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 long   flags;
 
-       BUG_ON(is_sync_kiocb(kiocb));
-
-       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);
-       }
-
        if (iocb->ki_list.next) {
                unsigned long flags;
 
@@ -1163,11 +1141,12 @@ 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)
+       if (iocb->ki_eventfd) {
                eventfd_signal(iocb->ki_eventfd, 1);
+               eventfd_ctx_put(iocb->ki_eventfd);
+       }
 
-       /* everything turned out well, dispose of the aiocb. */
-       kiocb_free(iocb);
+       kmem_cache_free(kiocb_cachep, iocb);
 
        /*
         * We have to order our ring_info tail store above and test
@@ -1430,6 +1409,47 @@ SYSCALL_DEFINE1(io_destroy, aio_context_t, ctx)
        return -EINVAL;
 }
 
+static void aio_complete_rw(struct kiocb *kiocb, long res, long res2)
+{
+       struct aio_kiocb *iocb = container_of(kiocb, struct aio_kiocb, rw);
+
+       WARN_ON_ONCE(is_sync_kiocb(kiocb));
+
+       if (kiocb->ki_flags & IOCB_WRITE) {
+               struct inode *inode = file_inode(kiocb->ki_filp);
+
+               /*
+                * Tell lockdep we inherited freeze protection from submission
+                * thread.
+                */
+               if (S_ISREG(inode->i_mode))
+                       __sb_writers_acquired(inode->i_sb, SB_FREEZE_WRITE);
+               file_end_write(kiocb->ki_filp);
+       }
+
+       fput(kiocb->ki_filp);
+       aio_complete(iocb, res, res2);
+}
+
+static int aio_prep_rw(struct kiocb *req, struct iocb *iocb)
+{
+       int ret;
+
+       req->ki_filp = fget(iocb->aio_fildes);
+       if (unlikely(!req->ki_filp))
+               return -EBADF;
+       req->ki_complete = aio_complete_rw;
+       req->ki_pos = iocb->aio_offset;
+       req->ki_flags = iocb_flags(req->ki_filp);
+       if (iocb->aio_flags & IOCB_FLAG_RESFD)
+               req->ki_flags |= IOCB_EVENTFD;
+       req->ki_hint = file_write_hint(req->ki_filp);
+       ret = kiocb_set_rw_flags(req, iocb->aio_rw_flags);
+       if (unlikely(ret))
+               fput(req->ki_filp);
+       return ret;
+}
+
 static int aio_setup_rw(int rw, struct iocb *iocb, struct iovec **iovec,
                bool vectored, bool compat, struct iov_iter *iter)
 {
@@ -1449,7 +1469,7 @@ static int aio_setup_rw(int rw, struct iocb *iocb, struct 
iovec **iovec,
        return import_iovec(rw, buf, len, UIO_FASTIOV, iovec, iter);
 }
 
-static inline ssize_t aio_ret(struct kiocb *req, ssize_t ret)
+static inline ssize_t aio_rw_ret(struct kiocb *req, ssize_t ret)
 {
        switch (ret) {
        case -EIOCBQUEUED:
@@ -1465,7 +1485,7 @@ static inline ssize_t aio_ret(struct kiocb *req, ssize_t 
ret)
                ret = -EINTR;
                /*FALLTHRU*/
        default:
-               aio_complete(req, ret, 0);
+               aio_complete_rw(req, ret, 0);
                return 0;
        }
 }
@@ -1473,56 +1493,78 @@ static inline ssize_t aio_ret(struct kiocb *req, 
ssize_t ret)
 static ssize_t aio_read(struct kiocb *req, 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;
+       struct file *file;
        ssize_t ret;
 
+       ret = aio_prep_rw(req, iocb);
+       if (ret)
+               return ret;
+       file = req->ki_filp;
+
+       ret = -EBADF;
        if (unlikely(!(file->f_mode & FMODE_READ)))
-               return -EBADF;
+               goto out_fput;
+       ret = -EINVAL;
        if (unlikely(!file->f_op->read_iter))
-               return -EINVAL;
+               goto out_fput;
 
        ret = aio_setup_rw(READ, iocb, &iovec, vectored, compat, &iter);
        if (ret)
-               return ret;
+               goto out_fput;
        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));
+               ret = aio_rw_ret(req, call_read_iter(file, req, &iter));
        kfree(iovec);
+out_fput:
+       if (unlikely(ret && ret != -EIOCBQUEUED))
+               fput(file);
        return ret;
 }
 
 static ssize_t aio_write(struct kiocb *req, 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;
+       struct file *file;
        ssize_t ret;
 
+       ret = aio_prep_rw(req, iocb);
+       if (ret)
+               return ret;
+       file = req->ki_filp;
+
+       ret = -EBADF;
        if (unlikely(!(file->f_mode & FMODE_WRITE)))
-               return -EBADF;
+               goto out_fput;
+       ret = -EINVAL;
        if (unlikely(!file->f_op->write_iter))
-               return -EINVAL;
+               goto out_fput;
 
        ret = aio_setup_rw(WRITE, iocb, &iovec, vectored, compat, &iter);
        if (ret)
-               return ret;
+               goto out_fput;
        ret = rw_verify_area(WRITE, file, &req->ki_pos, iov_iter_count(&iter));
        if (!ret) {
+               struct inode *inode = file_inode(file);
+
                req->ki_flags |= IOCB_WRITE;
                file_start_write(file);
-               ret = aio_ret(req, call_write_iter(file, req, &iter));
+               ret = aio_rw_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.
+                * We release freeze protection in aio_complete_rw().  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);
+               if (S_ISREG(inode->i_mode))
+                       __sb_writers_release(inode->i_sb, SB_FREEZE_WRITE);
        }
        kfree(iovec);
+out_fput:
+       if (unlikely(ret && ret != -EIOCBQUEUED))
+               fput(file);
        return ret;
 }
 
@@ -1530,7 +1572,6 @@ static int io_submit_one(struct kioctx *ctx, struct iocb 
__user *user_iocb,
                         struct iocb *iocb, bool compat)
 {
        struct aio_kiocb *req;
-       struct file *file;
        ssize_t ret;
 
        /* enforce forwards compatibility on users */
@@ -1553,16 +1594,6 @@ static int io_submit_one(struct kioctx *ctx, struct iocb 
__user *user_iocb,
        if (unlikely(!req))
                return -EAGAIN;
 
-       req->common.ki_filp = file = fget(iocb->aio_fildes);
-       if (unlikely(!req->common.ki_filp)) {
-               ret = -EBADF;
-               goto out_put_req;
-       }
-       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);
-
        if (iocb->aio_flags & IOCB_FLAG_RESFD) {
                /*
                 * If the IOCB_FLAG_RESFD flag of aio_flags is set, get an
@@ -1576,14 +1607,6 @@ static int io_submit_one(struct kioctx *ctx, struct iocb 
__user *user_iocb,
                        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;
        }
 
        ret = put_user(KIOCB_KEY, &user_iocb->aio_key);
@@ -1595,26 +1618,24 @@ static int io_submit_one(struct kioctx *ctx, struct 
iocb __user *user_iocb,
        req->ki_user_iocb = user_iocb;
        req->ki_user_data = iocb->aio_data;
 
-       get_file(file);
        switch (iocb->aio_lio_opcode) {
        case IOCB_CMD_PREAD:
-               ret = aio_read(&req->common, iocb, false, compat);
+               ret = aio_read(&req->rw, iocb, false, compat);
                break;
        case IOCB_CMD_PWRITE:
-               ret = aio_write(&req->common, iocb, false, compat);
+               ret = aio_write(&req->rw, iocb, false, compat);
                break;
        case IOCB_CMD_PREADV:
-               ret = aio_read(&req->common, iocb, true, compat);
+               ret = aio_read(&req->rw, iocb, true, compat);
                break;
        case IOCB_CMD_PWRITEV:
-               ret = aio_write(&req->common, iocb, true, compat);
+               ret = aio_write(&req->rw, iocb, true, compat);
                break;
        default:
                pr_debug("invalid aio operation %d\n", iocb->aio_lio_opcode);
                ret = -EINVAL;
                break;
        }
-       fput(file);
 
        if (ret && ret != -EIOCBQUEUED)
                goto out_put_req;
@@ -1622,7 +1643,9 @@ static int io_submit_one(struct kioctx *ctx, struct iocb 
__user *user_iocb,
 out_put_req:
        put_reqs_available(ctx, 1);
        percpu_ref_put(&ctx->reqs);
-       kiocb_free(req);
+       if (req->ki_eventfd)
+               eventfd_ctx_put(req->ki_eventfd);
+       kmem_cache_free(kiocb_cachep, req);
        return ret;
 }
 
-- 
2.14.2

Reply via email to