diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h index 366d366399407328dabe262b441a4b99801b071a..61b126b97885954a3008ede83fa33f11efc50df9 100644 --- a/arch/x86/include/asm/setup.h +++ b/arch/x86/include/asm/setup.h @@ -104,6 +104,29 @@ extern struct boot_params boot_params; extern unsigned long _brk_end; void *extend_brk(size_t size, size_t align); +/* + * Reserve space in the brk section. The name must be unique within + * the file, and somewhat descriptive. The size is in bytes. Must be + * used at file scope. + * + * (This uses a temp function to wrap the asm so we can pass it the + * size parameter; otherwise we wouldn't be able to. We can't use a + * "section" attribute on a normal variable because it always ends up + * being @progbits, which ends up allocating space in the vmlinux + * executable.) + */ +#define RESERVE_BRK(name,sz) \ + static void __section(.discard) __used \ + __brk_reservation_fn_##name##__(void) { \ + asm volatile ( \ + ".pushsection .brk_reservation,\"aw\",@nobits;" \ + "__brk_reservation_" #name "__:" \ + " 1:.skip %c0;" \ + " .size __brk_reservation_" #name "__, . - 1b;" \ + " .popsection" \ + : : "i" (sz)); \ + } + #ifdef __i386__ void __init i386_start_kernel(void); @@ -115,6 +138,13 @@ void __init x86_64_start_reservations(char *real_mode_data); #endif /* __i386__ */ #endif /* _SETUP */ +#else +#define RESERVE_BRK(name,sz) \ + .pushsection .brk_reservation,"aw",@nobits; \ +__brk_reservation_##name##__: \ +1: .skip sz; \ + .size __brk_reservation_##name##__,.-1b; \ + .popsection #endif /* __ASSEMBLY__ */ #endif /* __KERNEL__ */ diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index 3ce5456dfbe6b091f3ccd2a9ab28cf0cc0ac3fd6..9e89f2a14b90502b98d61a1a9dc0dc0bf4b2f7fe 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -75,6 +75,8 @@ ALLOCATOR_SLOP = 4 INIT_MAP_BEYOND_END = BOOTBITMAP_SIZE + (PAGE_TABLE_SIZE + ALLOCATOR_SLOP)*PAGE_SIZE_asm +RESERVE_BRK(pagetables, PAGE_TABLE_SIZE * PAGE_SIZE) + /* * 32-bit kernel entrypoint; only used by the boot CPU. On entry, * %esi points to the real-mode code as a 32-bit pointer. diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index e894f36335f21e54151b48e277cc431e1ae57f70..a0d26237d7cf141462a2d20941f8bd99d4195e57 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -112,6 +112,8 @@ #define ARCH_SETUP #endif +RESERVE_BRK(dmi_alloc, 65536); + unsigned int boot_cpu_id __read_mostly; static __initdata unsigned long _brk_start = (unsigned long)__brk_base; diff --git a/arch/x86/kernel/vmlinux_32.lds.S b/arch/x86/kernel/vmlinux_32.lds.S index 1063fbe93c73c1311a25956b69b881c619f3e3c6..a1f28b85fb3415cd44cedcf083397a6883c924f6 100644 --- a/arch/x86/kernel/vmlinux_32.lds.S +++ b/arch/x86/kernel/vmlinux_32.lds.S @@ -192,7 +192,8 @@ SECTIONS . = ALIGN(PAGE_SIZE); __brk_base = . ; - . += 1024 * 1024 ; + . += 64 * 1024 ; /* 64k slop space */ + *(.brk_reservation) /* areas brk users have reserved */ __brk_limit = . ; _end = . ; @@ -201,6 +202,7 @@ SECTIONS /* Sections to be discarded */ /DISCARD/ : { *(.exitcall.exit) + *(.discard) } STABS_DEBUG diff --git a/arch/x86/kernel/vmlinux_64.lds.S b/arch/x86/kernel/vmlinux_64.lds.S index ff373423138cd6a0ddb32eac33f0bd1b98d8325a..7996687663a2bc53b2a815bb9c098a2c0468c008 100644 --- a/arch/x86/kernel/vmlinux_64.lds.S +++ b/arch/x86/kernel/vmlinux_64.lds.S @@ -250,7 +250,8 @@ SECTIONS . = ALIGN(PAGE_SIZE); __brk_base = . ; - . += 1024 * 1024 ; + . += 64 * 1024; /* 64k slop space */ + *(.brk_reservation) /* areas brk users have reserved */ __brk_limit = . ; } @@ -260,6 +261,7 @@ SECTIONS /DISCARD/ : { *(.exitcall.exit) *(.eh_frame) + *(.discard) } STABS_DEBUG