[RFC PATCH v1 00/12] Replace strstarts() by str_has_prefix()

[laniel_francis]

From: Francis Laniel <laniel_francis@xxxxxxxxxxxxxxxxxxx>

Hi.


First, I hope you are fine and the same for your relatives.

In this patch set, I replaced all calls to strstarts() by calls to
str_has_prefix().
Indeed, the kernel has two functions to test if a string begins with an other:
1. strstarts() which returns a bool, so 1 if the string begins with the prefix,
0 otherwise.
2. str_has_prefix() which returns the length of the prefix or 0.

str_has_prefix() was introduced later than strstarts(), in commit 495d714ad140
which also stated that str_has_prefix() should replace strstarts().
This is what this patch set does.

Concerning the patches, the modifications cover different areas of the kernel.
I compiled all of them and they compile smoothly.
Unfortunately, I did not test all of them, so here are the status of the patches
regarding test:
1. Tested with qemu-system-arm using insmod.
2. I do not have access to a bcm47xx MIPS CPU an qemu-system-mips does not
emulate this board.
3. Tested with qemu-system-x86_64 calling
crypto_alloc_skcipher("essiv(authenc(hmac(sha256),cbc(aes)),sha256)", 0, 0)
through LKDTM.
4. Tested with qemu-system-x86_64 using crypsetup.
5. I do not have access to a renesas board and I lack some context to test it
with qemu-system-arm.
6. I do not have access to an OMAP board and I lack some context to test it with
qemu-system-arm.
7. I did not find how to boot from the EFI_STUB with qemu. If you know how to
do, I would be happy to try running this code.
8. I ran qemu-system-x86_64 with a floppy disk attached but impossible to go
through this module code...
9. I do not have access to a bcm63xx MIPS CPU an qemu-system-mips does not
emulate this board.
10. Tested with qemu-system-x86_64 using insmod.
11. I do not have access to an AM335x or DA8xx platforms and I lack some context
to test it with qemu-system-arm.

If you see a way to improve the patches or if I did something wrong with the
mail do not hesitate to ask.


Best regards.

Francis Laniel (12):
  arm: Replace strstarts() by str_has_prefix().
  mips: Replace strstarts() by str_has_prefix().
  crypto: Replace strstarts() by str_has_prefix().
  device-mapper: Replace strstarts() by str_has_prefix().
  renesas: Replace strstarts() by str_has_prefix().
  omap: Replace strstarts() by str_has_prefix().
  efi: Replace strstarts() by str_has_prefix().
  ide: Replace strstarts() by str_has_prefix().
  mips: Replace strstarts() by str_has_prefix().
  module: Replace strstarts() by str_has_prefix().
  musb: Replace strstarts() by str_has_prefix().
  string.h: Remove strstarts().

 arch/arm/kernel/module.c                      | 12 +++++------
 arch/mips/bcm47xx/board.c                     |  4 ++--
 arch/mips/bcm63xx/boards/board_bcm963xx.c     |  2 +-
 crypto/essiv.c                                |  2 +-
 .../firmware/efi/libstub/efi-stub-helper.c    |  2 +-
 drivers/firmware/efi/libstub/gop.c            | 10 +++++-----
 drivers/gpu/drm/omapdrm/dss/base.c            |  2 +-
 drivers/gpu/drm/rcar-du/rcar_du_crtc.c        |  2 +-
 drivers/ide/ide-floppy.c                      |  4 ++--
 drivers/md/dm-crypt.c                         |  4 ++--
 drivers/usb/musb/musb_cppi41.c                |  4 ++--
 drivers/usb/musb/musb_debugfs.c               | 20 +++++++++----------
 include/linux/string.h                        | 10 ----------
 kernel/module.c                               |  6 +++---
 14 files changed, 37 insertions(+), 47 deletions(-)

-- 
2.20.1