UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

posix_types.h: Cleanup stale __NFDBITS and related definitions 

Recently, glibc made a change to suppress sign-conversion warnings in
FD_SET (glibc commit ceb9e56b3d1).  This uncovered an issue with the
kernel's definition of __NFDBITS if applications #include
<linux/types.h> after including <sys/select.h>.  A build failure would
be seen when passing the -Werror=sign-compare and -D_FORTIFY_SOURCE=2
flags to gcc.

It was suggested that the kernel should either match the glibc
definition of __NFDBITS or remove that entirely.  The current in-kernel
uses of __NFDBITS can be replaced with BITS_PER_LONG, and there are no
uses of the related __FDELT and __FDMASK defines.  Given that, we'll
continue the cleanup that was started with commit 8b3d1cda4f
("posix_types: Remove fd_set macros") and drop the remaining unused
macros.

Additionally, linux/time.h has similar macros defined that expand to
nothing so we'll remove those at the same time.

Reported-by: Jeff Law <law@redhat.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
CC: <stable@vger.kernel.org>
Signed-off-by: Josh Boyer <jwboyer@redhat.com>
[ .. and fix up whitespace as per akpm ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Josh Boyer 2012-07-25 10:40:34 -04:00 committed by Linus Torvalds
parent 4cb38750d4
commit 8ded2bbc18
7 changed files with 12 additions and 32 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/mips/kernel/kspd.c
View File

@ -323,7 +323,7 @@ static void sp_cleanup(void)
fdt = files_fdtable(files);
for (;;) {
unsigned long set;
i = j * __NFDBITS;
i = j * BITS_PER_LONG;
if (i >= fdt->max_fds)
break;
set = fdt->open_fds[j++];

2
fs/exec.c
View File

@ -1020,7 +1020,7 @@ static void flush_old_files(struct files_struct * files)
unsigned long set, i;
j++;
i = j * __NFDBITS;
i = j * BITS_PER_LONG;
fdt = files_fdtable(files);
if (i >= fdt->max_fds)
break;

10
fs/select.c
View File

@ -345,8 +345,8 @@ static int max_select_fd(unsigned long n, fd_set_bits *fds)
struct fdtable *fdt;
/* handle last in-complete long-word first */
set = ~(~0UL << (n & (__NFDBITS-1)));
n /= __NFDBITS;
set = ~(~0UL << (n & (BITS_PER_LONG-1)));
n /= BITS_PER_LONG;
fdt = files_fdtable(current->files);
open_fds = fdt->open_fds + n;
max = 0;
@ -373,7 +373,7 @@ get_max:
max++;
set >>= 1;
} while (set);
max += n * __NFDBITS;
max += n * BITS_PER_LONG;
}
return max;
@ -435,11 +435,11 @@ int do_select(int n, fd_set_bits *fds, struct timespec *end_time)
in = *inp++; out = *outp++; ex = *exp++;
all_bits = in | out | ex;
if (all_bits == 0) {
i += __NFDBITS;
i += BITS_PER_LONG;
continue;
}
for (j = 0; j < __NFDBITS; ++j, ++i, bit <<= 1) {
for (j = 0; j < BITS_PER_LONG; ++j, ++i, bit <<= 1) {
int fput_needed;
if (i >= n)
break;

18
include/linux/posix_types.h
View File

@ -15,26 +15,14 @@
*/
/*
* Those macros may have been defined in <gnu/types.h>. But we always
* use the ones here.
* This macro may have been defined in <gnu/types.h>. But we always
* use the one here.
*/
#undef __NFDBITS
#define __NFDBITS (8 * sizeof(unsigned long))
#undef __FD_SETSIZE
#define __FD_SETSIZE 1024
#undef __FDSET_LONGS
#define __FDSET_LONGS (__FD_SETSIZE/__NFDBITS)
#undef __FDELT
#define __FDELT(d) ((d) / __NFDBITS)
#undef __FDMASK
#define __FDMASK(d) (1UL << ((d) % __NFDBITS))
typedef struct {
unsigned long fds_bits [__FDSET_LONGS];
unsigned long fds_bits[__FD_SETSIZE / (8 * sizeof(long))];
} __kernel_fd_set;
/* Type of a signal handler. */

8
include/linux/time.h
View File

@ -257,14 +257,6 @@ static __always_inline void timespec_add_ns(struct timespec *a, u64 ns)
#endif /* __KERNEL__ */
#define NFDBITS __NFDBITS
#define FD_SETSIZE __FD_SETSIZE
#define FD_SET(fd,fdsetp) __FD_SET(fd,fdsetp)
#define FD_CLR(fd,fdsetp) __FD_CLR(fd,fdsetp)
#define FD_ISSET(fd,fdsetp) __FD_ISSET(fd,fdsetp)
#define FD_ZERO(fdsetp) __FD_ZERO(fdsetp)
/*
* Names of the interval timers, and structure
* defining a timer setting:

2
kernel/exit.c
View File

@ -483,7 +483,7 @@ static void close_files(struct files_struct * files)
rcu_read_unlock();
for (;;) {
unsigned long set;
i = j * __NFDBITS;
i = j * BITS_PER_LONG;
if (i >= fdt->max_fds)
break;
set = fdt->open_fds[j++];

2
security/selinux/hooks.c
View File

@ -2129,7 +2129,7 @@ static inline void flush_unauthorized_files(const struct cred *cred,
int fd;
j++;
i = j * __NFDBITS;
i = j * BITS_PER_LONG;
fdt = files_fdtable(files);
if (i >= fdt->max_fds)
break;