arch/alpha/kernel/io.c:425:46: sparse: sparse: cast removes address space '__iomem' of expression

From: kernel test robot
Date: Sat Dec 09 2023 - 20:26:20 EST

tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 21b73ffcc62ab772bc06e3e90bd87eff5e9e8ed4
commit: d15155824c5014803d91b829736d249c500bdda6 linux/compiler.h: Split into compiler.h and compiler_types.h
date: 6 years ago
config: alpha-randconfig-r113-20231116 (https://download.01.org/0day-ci/archive/20231210/202312100904.XepiU7RJ-lkp@xxxxxxxxx/config)
compiler: alpha-linux-gcc (GCC) 13.2.0
reproduce: (https://download.01.org/0day-ci/archive/20231210/202312100904.XepiU7RJ-lkp@xxxxxxxxx/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-kbuild-all/202312100904.XepiU7RJ-lkp@xxxxxxxxx/

sparse warnings: (new ones prefixed by >>)
arch/alpha/kernel/io.c:620:14: sparse: sparse: multiple definitions for function 'ioport_map'
arch/alpha/kernel/io.c: note: in included file:
arch/alpha/include/asm/io.h:276:28: sparse: the previous one is here
arch/alpha/kernel/io.c:625:6: sparse: sparse: multiple definitions for function 'ioport_unmap'
arch/alpha/include/asm/io.h:281:20: sparse: the previous one is here
>> arch/alpha/kernel/io.c:425:46: sparse: sparse: cast removes address space '__iomem' of expression
arch/alpha/kernel/io.c:436:46: sparse: sparse: cast removes address space '__iomem' of expression
arch/alpha/kernel/io.c:447:46: sparse: sparse: cast removes address space '__iomem' of expression
arch/alpha/kernel/io.c:480:29: sparse: sparse: cast removes address space '__iomem' of expression
arch/alpha/kernel/io.c:491:29: sparse: sparse: cast removes address space '__iomem' of expression
arch/alpha/kernel/io.c:502:29: sparse: sparse: cast removes address space '__iomem' of expression
arch/alpha/kernel/io.c:531:28: sparse: sparse: cast removes address space '__iomem' of expression
arch/alpha/kernel/io.c:538:29: sparse: sparse: cast removes address space '__iomem' of expression
arch/alpha/kernel/io.c:545:29: sparse: sparse: cast removes address space '__iomem' of expression
In file included from include/linux/workqueue.h:8,
from include/linux/srcu.h:34,
from include/linux/notifier.h:15,
from include/linux/memory_hotplug.h:6,
from include/linux/mmzone.h:779,
from include/linux/gfp.h:5,
from include/linux/umh.h:4,
from include/linux/kmod.h:22,
from include/linux/module.h:13,
from arch/alpha/kernel/io.c:8:
include/linux/timer.h: In function 'timer_setup':
include/linux/timer.h:178:30: warning: cast between incompatible function types from 'void (*)(struct timer_list *)' to 'void (*)(long unsigned int)' [-Wcast-function-type]
178 | __setup_timer(timer, (TIMER_FUNC_TYPE)callback,
| ^
include/linux/timer.h:143:39: note: in definition of macro '__setup_timer'
143 | (_timer)->function = (_fn); 32- | ^~~
arch/alpha/kernel/io.c: At top level:
arch/alpha/kernel/io.c:590:1: warning: no previous prototype for 'scr_memcpyw' [-Wmissing-prototypes]
590 | scr_memcpyw(u16 *d, const u16 *s, unsigned int count)
| ^~~~~~~~~~~

vim +/__iomem +425 arch/alpha/kernel/io.c

^1da177e4c3f41 Linus Torvalds 2005-04-16 414
^1da177e4c3f41 Linus Torvalds 2005-04-16 415
^1da177e4c3f41 Linus Torvalds 2005-04-16 416 /*
^1da177e4c3f41 Linus Torvalds 2005-04-16 417 * Copy data from IO memory space to "real" memory space.
^1da177e4c3f41 Linus Torvalds 2005-04-16 418 * This needs to be optimized.
^1da177e4c3f41 Linus Torvalds 2005-04-16 419 */
^1da177e4c3f41 Linus Torvalds 2005-04-16 420 void memcpy_fromio(void *to, const volatile void __iomem *from, long count)
^1da177e4c3f41 Linus Torvalds 2005-04-16 421 {
^1da177e4c3f41 Linus Torvalds 2005-04-16 422 /* Optimize co-aligned transfers. Everything else gets handled
^1da177e4c3f41 Linus Torvalds 2005-04-16 423 a byte at a time. */
^1da177e4c3f41 Linus Torvalds 2005-04-16 424
^1da177e4c3f41 Linus Torvalds 2005-04-16 @425 if (count >= 8 && ((u64)to & 7) == ((u64)from & 7)) {
^1da177e4c3f41 Linus Torvalds 2005-04-16 426 count -= 8;
^1da177e4c3f41 Linus Torvalds 2005-04-16 427 do {
^1da177e4c3f41 Linus Torvalds 2005-04-16 428 *(u64 *)to = __raw_readq(from);
^1da177e4c3f41 Linus Torvalds 2005-04-16 429 count -= 8;
^1da177e4c3f41 Linus Torvalds 2005-04-16 430 to += 8;
^1da177e4c3f41 Linus Torvalds 2005-04-16 431 from += 8;
^1da177e4c3f41 Linus Torvalds 2005-04-16 432 } while (count >= 0);
^1da177e4c3f41 Linus Torvalds 2005-04-16 433 count += 8;
^1da177e4c3f41 Linus Torvalds 2005-04-16 434 }
^1da177e4c3f41 Linus Torvalds 2005-04-16 435
^1da177e4c3f41 Linus Torvalds 2005-04-16 436 if (count >= 4 && ((u64)to & 3) == ((u64)from & 3)) {
^1da177e4c3f41 Linus Torvalds 2005-04-16 437 count -= 4;
^1da177e4c3f41 Linus Torvalds 2005-04-16 438 do {
^1da177e4c3f41 Linus Torvalds 2005-04-16 439 *(u32 *)to = __raw_readl(from);
^1da177e4c3f41 Linus Torvalds 2005-04-16 440 count -= 4;
^1da177e4c3f41 Linus Torvalds 2005-04-16 441 to += 4;
^1da177e4c3f41 Linus Torvalds 2005-04-16 442 from += 4;
^1da177e4c3f41 Linus Torvalds 2005-04-16 443 } while (count >= 0);
^1da177e4c3f41 Linus Torvalds 2005-04-16 444 count += 4;
^1da177e4c3f41 Linus Torvalds 2005-04-16 445 }
^1da177e4c3f41 Linus Torvalds 2005-04-16 446
^1da177e4c3f41 Linus Torvalds 2005-04-16 447 if (count >= 2 && ((u64)to & 1) == ((u64)from & 1)) {
^1da177e4c3f41 Linus Torvalds 2005-04-16 448 count -= 2;
^1da177e4c3f41 Linus Torvalds 2005-04-16 449 do {
^1da177e4c3f41 Linus Torvalds 2005-04-16 450 *(u16 *)to = __raw_readw(from);
^1da177e4c3f41 Linus Torvalds 2005-04-16 451 count -= 2;
^1da177e4c3f41 Linus Torvalds 2005-04-16 452 to += 2;
^1da177e4c3f41 Linus Torvalds 2005-04-16 453 from += 2;
^1da177e4c3f41 Linus Torvalds 2005-04-16 454 } while (count >= 0);
^1da177e4c3f41 Linus Torvalds 2005-04-16 455 count += 2;
^1da177e4c3f41 Linus Torvalds 2005-04-16 456 }
^1da177e4c3f41 Linus Torvalds 2005-04-16 457
^1da177e4c3f41 Linus Torvalds 2005-04-16 458 while (count > 0) {
^1da177e4c3f41 Linus Torvalds 2005-04-16 459 *(u8 *) to = __raw_readb(from);
^1da177e4c3f41 Linus Torvalds 2005-04-16 460 count--;
^1da177e4c3f41 Linus Torvalds 2005-04-16 461 to++;
^1da177e4c3f41 Linus Torvalds 2005-04-16 462 from++;
^1da177e4c3f41 Linus Torvalds 2005-04-16 463 }
^1da177e4c3f41 Linus Torvalds 2005-04-16 464 mb();
^1da177e4c3f41 Linus Torvalds 2005-04-16 465 }
^1da177e4c3f41 Linus Torvalds 2005-04-16 466

:::::: The code at line 425 was first introduced by commit
:::::: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Linux-2.6.12-rc2

:::::: TO: Linus Torvalds <torvalds@xxxxxxxxxxxxxxx>
:::::: CC: Linus Torvalds <torvalds@xxxxxxxxxxxxxxx>

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