| /* |
| * cmpxchg*() fallbacks for CPU not supporting these instructions |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/smp.h> |
| #include <linux/module.h> |
| |
| #ifndef CONFIG_X86_CMPXCHG |
| unsigned long cmpxchg_386_u8(volatile void *ptr, u8 old, u8 new) |
| { |
| u8 prev; |
| unsigned long flags; |
| |
| /* Poor man's cmpxchg for 386. Unsuitable for SMP */ |
| local_irq_save(flags); |
| prev = *(u8 *)ptr; |
| if (prev == old) |
| *(u8 *)ptr = new; |
| local_irq_restore(flags); |
| return prev; |
| } |
| EXPORT_SYMBOL(cmpxchg_386_u8); |
| |
| unsigned long cmpxchg_386_u16(volatile void *ptr, u16 old, u16 new) |
| { |
| u16 prev; |
| unsigned long flags; |
| |
| /* Poor man's cmpxchg for 386. Unsuitable for SMP */ |
| local_irq_save(flags); |
| prev = *(u16 *)ptr; |
| if (prev == old) |
| *(u16 *)ptr = new; |
| local_irq_restore(flags); |
| return prev; |
| } |
| EXPORT_SYMBOL(cmpxchg_386_u16); |
| |
| unsigned long cmpxchg_386_u32(volatile void *ptr, u32 old, u32 new) |
| { |
| u32 prev; |
| unsigned long flags; |
| |
| /* Poor man's cmpxchg for 386. Unsuitable for SMP */ |
| local_irq_save(flags); |
| prev = *(u32 *)ptr; |
| if (prev == old) |
| *(u32 *)ptr = new; |
| local_irq_restore(flags); |
| return prev; |
| } |
| EXPORT_SYMBOL(cmpxchg_386_u32); |
| #endif |
