Re: [PATCH v3 3/3] fs: Add aio iopriority support for block_dev

[kbuild test robot]

Hi Adam,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on linus/master]
[also build test ERROR on v4.17-rc4 next-20180508]
[if your patch is applied to the wrong git tree, please drop us a note to help 
improve the system]

url:
https://github.com/0day-ci/linux/commits/adam-manzanares-wdc-com/block-add-ioprio_check_cap-function/20180509-094058
config: x86_64-randconfig-s0-05091255 (attached as .config)
compiler: gcc-6 (Debian 6.4.0-9) 6.4.0 20171026
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64 

All errors (new ones prefixed by >>):

   fs/aio.c: In function 'io_submit_one':
>> fs/aio.c:1606:9: error: implicit declaration of function 'ioprio_check_cap' 
>> [-Werror=implicit-function-declaration]
  ret = ioprio_check_cap(iocb->aio_reqprio);
^~~~
   cc1: some warnings being treated as errors

vim +/ioprio_check_cap +1606 fs/aio.c

  1545  
  1546  static int io_submit_one(struct kioctx *ctx, struct iocb __user 
*user_iocb,
  1547   struct iocb *iocb, bool compat)
  1548  {
  1549  struct aio_kiocb *req;
  1550  struct file *file;
  1551  ssize_t ret;
  1552  
  1553  /* enforce forwards compatibility on users */
  1554  if (unlikely(iocb->aio_reserved2)) {
  1555  pr_debug("EINVAL: reserve field set\n");
  1556  return -EINVAL;
  1557  }
  1558  
  1559  /* prevent overflows */
  1560  if (unlikely(
  1561  (iocb->aio_buf != (unsigned long)iocb->aio_buf) ||
  1562  (iocb->aio_nbytes != (size_t)iocb->aio_nbytes) ||
  1563  ((ssize_t)iocb->aio_nbytes < 0)
  1564 )) {
  1565  pr_debug("EINVAL: overflow check\n");
  1566  return -EINVAL;
  1567  }
  1568  
  1569  req = aio_get_req(ctx);
  1570  if (unlikely(!req))
  1571  return -EAGAIN;
  1572  
  1573  req->common.ki_filp = file = fget(iocb->aio_fildes);
  1574  if (unlikely(!req->common.ki_filp)) {
  1575  ret = -EBADF;
  1576  goto out_put_req;
  1577  }
  1578  req->common.ki_pos = iocb->aio_offset;
  1579  req->common.ki_complete = aio_complete;
  1580  req->common.ki_flags = iocb_flags(req->common.ki_filp);
  1581  req->common.ki_hint = file_write_hint(file);
  1582  
  1583  if (iocb->aio_flags & IOCB_FLAG_RESFD) {
  1584  /*
  1585   * If the IOCB_FLAG_RESFD flag of aio_flags is set, get 
an
  1586   * instance of the file* now. The file descriptor must 
be
  1587   * an eventfd() fd, and will be signaled for each 
completed
  1588   * event using the eventfd_signal() function.
  1589   */
  1590  req->ki_eventfd = eventfd_ctx_fdget((int) 
iocb->aio_resfd);
  1591  if (IS_ERR(req->ki_eventfd)) {
  1592  ret = PTR_ERR(req->ki_eventfd);
  1593  req->ki_eventfd = NULL;
  1594  goto out_put_req;
  1595  }
  1596  
  1597  req->common.ki_flags |= IOCB_EVENTFD;
  1598  }
  1599  
  1600  if (iocb->aio_flags & IOCB_FLAG_IOPRIO) {
  1601  /*
  1602   * If the IOCB_FLAG_IOPRIO flag of aio_flags is set, 
then
  1603   * aio_reqprio is interpreted as an I/O scheduling
  1604   * class and priority.
  1605   */
> 1606  ret = ioprio_check_cap(iocb->aio_reqprio);
  1607  if (ret) {
  1608  pr_debug("aio ioprio check cap error\n");
  1609  goto out_put_req;
  1610  }
  1611  
  1612  req->common.ki_ioprio = iocb->aio_reqprio;
  1613  req->common.ki_flags |= IOCB_IOPRIO;
  1614  }
  1615  
  1616  ret = kiocb_set_rw_flags(>common, iocb->aio_rw_flags);
  1617  if (unlikely(ret)) {
  1618  pr_debug("EINVAL: aio_rw_flags\n");
  1619  goto out_put_req;
  1620  }
  1621  
  1622  ret = put_user(KIOCB_KEY, _iocb->aio_key);
  1623  if (unlikely(ret)) {
  1624  pr_debug("EFAULT: aio_key\n");
  1625  goto out_put_req;
  1626  }
  1627  
  1628  req->ki_user_iocb = user_iocb;
  1629  req->ki_user_data = iocb->aio_data;
  1630  
  1631  get_file(file);
  1632  switch (iocb->aio_lio_opcode) {
  1633  case IOCB_CMD_PREAD:
  1634  ret = aio_read(>common, iocb, false, compat);
  1635  break;
  1636  case IOCB_CMD_PWRITE:
  1637  ret = aio_write(>common, iocb, false, compat);
  1638  

[PATCH v3 3/3] fs: Add aio iopriority support for block_dev

[adam . manzanares]

From: Adam Manzanares 

When IOCB_FLAG_IOPRIO is set on the iocb aio_flags field, then we set the
newly added kiocb ki_ioprio field to the value in the iocb aio_reqprio field.

When a bio is created for an aio request by the block dev we set the priority
value of the bio to the user supplied value.

Signed-off-by: Adam Manzanares 
---
 fs/aio.c | 16 
 fs/block_dev.c   |  2 ++
 include/linux/fs.h   |  2 ++
 include/uapi/linux/aio_abi.h |  1 +
 4 files changed, 21 insertions(+)

diff --git a/fs/aio.c b/fs/aio.c
index 88d7927ffbc6..f43d1d3a2e39 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1597,6 +1597,22 @@ static int io_submit_one(struct kioctx *ctx, struct iocb 
__user *user_iocb,
req->common.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\n");
+   goto out_put_req;
+   }
+
+   req->common.ki_ioprio = iocb->aio_reqprio;
+   req->common.ki_flags |= IOCB_IOPRIO;
+   }
+
ret = kiocb_set_rw_flags(>common, iocb->aio_rw_flags);
if (unlikely(ret)) {
pr_debug("EINVAL: aio_rw_flags\n");
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 7ec920e27065..970bef79caa6 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -355,6 +355,8 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter 
*iter, int nr_pages)
bio->bi_write_hint = iocb->ki_hint;
bio->bi_private = dio;
bio->bi_end_io = blkdev_bio_end_io;
+   if (iocb->ki_flags & IOCB_IOPRIO)
+   bio->bi_ioprio = iocb->ki_ioprio;
 
ret = bio_iov_iter_get_pages(bio, iter);
if (unlikely(ret)) {
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 7a90ce387e00..3415e83f6350 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -294,6 +294,7 @@ enum rw_hint {
 #define IOCB_SYNC  (1 << 5)
 #define IOCB_WRITE (1 << 6)
 #define IOCB_NOWAIT(1 << 7)
+#define IOCB_IOPRIO(1 << 8)
 
 struct kiocb {
struct file *ki_filp;
@@ -302,6 +303,7 @@ struct kiocb {
void*private;
int ki_flags;
u16 ki_hint;
+   u16 ki_ioprio; /* See linux/ioprio.h */
 } __randomize_layout;
 
 static inline bool is_sync_kiocb(struct kiocb *kiocb)
diff --git a/include/uapi/linux/aio_abi.h b/include/uapi/linux/aio_abi.h
index a04adbc70ddf..d4593a6062ef 100644
--- a/include/uapi/linux/aio_abi.h
+++ b/include/uapi/linux/aio_abi.h
@@ -54,6 +54,7 @@ enum {
  *   is valid.
  */
 #define IOCB_FLAG_RESFD(1 << 0)
+#define IOCB_FLAG_IOPRIO   (1 << 1)
 
 /* read() from /dev/aio returns these structures. */
 struct io_event {
-- 
2.15.1