[LTP] [PATCH v3 1/3] lib: alter find_free_loopdev()

[Amir Goldstein]

On Wed, Jul 10, 2019 at 10:18 AM Yang Xu <xuyang2018.jy@cn.fujitsu.com> wrote:
>
> Alter find_free_loopdev() to return the free loopdev minor
> (and -1 for no free loopdev) and then WE can safely use the
> minor number that find_free_loopdev() returned in test cases.
>
> Signed-off-by: Yang Xu <xuyang2018.jy@cn.fujitsu.com>

Reviewed-by: Amir Goldstein <amir73il@gmail.com>

> ---
>  doc/test-writing-guidelines.txt |  9 +++++++++
>  include/tst_device.h            |  6 ++++++
>  lib/tst_device.c                | 12 ++++++------
>  3 files changed, 21 insertions(+), 6 deletions(-)
>
> diff --git a/doc/test-writing-guidelines.txt b/doc/test-writing-guidelines.txt
> index c6d4e001d..887801e68 100644
> --- a/doc/test-writing-guidelines.txt
> +++ b/doc/test-writing-guidelines.txt
> @@ -1045,6 +1045,15 @@ IMPORTANT: All testcases should use 'tst_umount()' instead of 'umount(2)' to
>  -------------------------------------------------------------------------------
>  #include "tst_test.h"
>
> +int find_free_loopdev();
> +-------------------------------------------------------------------------------
> +This function finds a free loopdev for use and returns the free loopdev minor(-1
> +for no free loopdev).
> +
> +[source,c]
> +-------------------------------------------------------------------------------
> +#include "tst_test.h"
> +
>  unsigned long tst_dev_bytes_written(const char *dev);
>  -------------------------------------------------------------------------------
>
> diff --git a/include/tst_device.h b/include/tst_device.h
> index 61902b7e0..8953b0828 100644
> --- a/include/tst_device.h
> +++ b/include/tst_device.h
> @@ -44,6 +44,12 @@ int tst_umount(const char *path);
>   */
>  int tst_clear_device(const char *dev);
>
> +/*
> + * Finds a free loop device for use and returns the free loopdev minor(-1 for no
> + * free loopdev).
> + */
> +int find_free_loopdev(void);
> +
>  /*
>   * Reads test block device stat file and returns the bytes written since the
>   * last call of this function.
> diff --git a/lib/tst_device.c b/lib/tst_device.c
> index 65fcc1337..3b87dd1f1 100644
> --- a/lib/tst_device.c
> +++ b/lib/tst_device.c
> @@ -68,7 +68,7 @@ static int set_dev_path(int dev)
>         return 0;
>  }
>
> -static int find_free_loopdev(void)
> +int find_free_loopdev(void)
>  {
>         int ctl_fd, dev_fd, rc, i;
>         struct loop_info loopinfo;
> @@ -82,10 +82,10 @@ static int find_free_loopdev(void)
>                 if (rc >= 0) {
>                         set_dev_path(rc);
>                         tst_resm(TINFO, "Found free device '%s'", dev_path);
> -                       return 0;
> +                       return rc;
>                 }
>                 tst_resm(TINFO, "Couldn't find free loop device");
> -               return 1;
> +               return -1;
>         }
>
>         switch (errno) {
> @@ -121,7 +121,7 @@ static int find_free_loopdev(void)
>                                 continue;
>                         tst_resm(TINFO, "Found free device '%s'", dev_path);
>                         close(dev_fd);
> -                       return 0;
> +                       return i;
>                 }
>
>                 close(dev_fd);
> @@ -129,7 +129,7 @@ static int find_free_loopdev(void)
>
>         tst_resm(TINFO, "No free devices found");
>
> -       return 1;
> +       return -1;
>  }
>
>  static int attach_device(const char *dev, const char *file)
> @@ -274,7 +274,7 @@ const char *tst_acquire_device__(unsigned int size)
>                 return NULL;
>         }
>
> -       if (find_free_loopdev())
> +       if (find_free_loopdev() == -1)
>                 return NULL;
>
>         if (attach_device(dev_path, DEV_FILE))
> --
> 2.18.1
>
>
>