On Sun, Jun 04, 2017 at 02:59:51PM +0300, Yury Norov wrote: > All new 32-bit architectures should have 64-bit off_t type, but existing > architectures has 32-bit ones. > > To handle it, new config option is added to arch/Kconfig that defaults > ARCH_32BIT_OFF_T to be disabled for non-64 bit architectures. All existing > 32-bit architectures enable it explicitly here. > > New option affects force_o_largefile() behaviour. Namely, if off_t is > 64-bits long, we have no reason to reject user to open big files. > > Note that even if architectures has only 64-bit off_t in the kernel > (arc, c6x, h8300, hexagon, metag, nios2, openrisc, tile32 and unicore32), > a libc may use 32-bit off_t, and therefore want to limit the file size > to 4GB unless specified differently in the open flags. > > Signed-off-by: Yury Norov <ynorov@xxxxxxxxxxxxxxxxxx> > Acked-by: Arnd Bergmann <arnd@xxxxxxxx> [...] > diff --git a/include/linux/fcntl.h b/include/linux/fcntl.h > index 1b48d9c9a561..297993c92490 100644 > --- a/include/linux/fcntl.h > +++ b/include/linux/fcntl.h > @@ -11,7 +11,7 @@ > O_NOATIME | O_CLOEXEC | O_PATH | __O_TMPFILE) > > #ifndef force_o_largefile > -#define force_o_largefile() (BITS_PER_LONG != 32) > +#define force_o_largefile() (!IS_ENABLED(CONFIG_ARCH_32BIT_OFF_T)) > #endif I may have confused myself with which off_t is 64-bit here for new 32-bit architectures. Are we referring to the glibc definition, the kernel one or simply that force_o_largefile() is true by default. Because the type off_t for 32-bit kernel builds is still, well, 32-bit. Otherwise it seems that the first paragraph in the description above should read "all new 32-bit ABIs on a 64-bit kernel..." but then AArch64/ILP32 is no longer the same as a new, pure 32-bit architecture. -- Catalin -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
