From 64ca9004b819ab87648dbfc78f3ef49ee491343e Mon Sep 17 00:00:00 2001 From: Matt Mackall Date: Sun, 8 Jan 2006 01:05:26 -0800 Subject: [PATCH] [PATCH] Make vm86 support optional This adds an option to remove vm86 support under CONFIG_EMBEDDED. Saves about 5k. This version eliminates most of the #ifdefs of the previous version and instead uses function stubs in vm86.h. Also, release_vm86_irqs is moved from asm-i386/irq.h to a more appropriate home in vm86.h so that the stubs can live together. $ size vmlinux-baseline vmlinux-novm86 text data bss dec hex filename 2920821 523232 190652 3634705 377611 vmlinux-baseline 2916268 523100 190492 3629860 376324 vmlinux-novm86 Signed-off-by: Matt Mackall Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/kernel/Makefile | 3 ++- arch/i386/kernel/entry.S | 2 ++ arch/i386/kernel/process.c | 1 + include/asm-i386/irq.h | 2 -- include/asm-i386/vm86.h | 20 ++++++++++++++++++++ init/Kconfig | 10 ++++++++++ kernel/sys_ni.c | 2 ++ 7 files changed, 37 insertions(+), 3 deletions(-) diff --git a/arch/i386/kernel/Makefile b/arch/i386/kernel/Makefile index 4f40589e179c..be1880bb75b4 100644 --- a/arch/i386/kernel/Makefile +++ b/arch/i386/kernel/Makefile @@ -4,7 +4,7 @@ extra-y := head.o init_task.o vmlinux.lds -obj-y := process.o semaphore.o signal.o entry.o traps.o irq.o vm86.o \ +obj-y := process.o semaphore.o signal.o entry.o traps.o irq.o \ ptrace.o time.o ioport.o ldt.o setup.o i8259.o sys_i386.o \ pci-dma.o i386_ksyms.o i387.o dmi_scan.o bootflag.o \ quirks.o i8237.o @@ -34,6 +34,7 @@ obj-$(CONFIG_ACPI_SRAT) += srat.o obj-$(CONFIG_HPET_TIMER) += time_hpet.o obj-$(CONFIG_EFI) += efi.o efi_stub.o obj-$(CONFIG_DOUBLEFAULT) += doublefault.o +obj-$(CONFIG_VM86) += vm86.o obj-$(CONFIG_EARLY_PRINTK) += early_printk.o EXTRA_AFLAGS := -traditional diff --git a/arch/i386/kernel/entry.S b/arch/i386/kernel/entry.S index 607c06007508..4d704724b2f5 100644 --- a/arch/i386/kernel/entry.S +++ b/arch/i386/kernel/entry.S @@ -323,6 +323,7 @@ work_notifysig: # deal with pending signals and ALIGN work_notifysig_v86: +#ifdef CONFIG_VM86 pushl %ecx # save ti_flags for do_notify_resume call save_v86_state # %eax contains pt_regs pointer popl %ecx @@ -330,6 +331,7 @@ work_notifysig_v86: xorl %edx, %edx call do_notify_resume jmp resume_userspace +#endif # perform syscall exit tracing ALIGN diff --git a/arch/i386/kernel/process.c b/arch/i386/kernel/process.c index 45e7f0ac4b04..035928f3f6c1 100644 --- a/arch/i386/kernel/process.c +++ b/arch/i386/kernel/process.c @@ -48,6 +48,7 @@ #include #include #include +#include #ifdef CONFIG_MATH_EMULATION #include #endif diff --git a/include/asm-i386/irq.h b/include/asm-i386/irq.h index 270f1986b19f..5169d7af456f 100644 --- a/include/asm-i386/irq.h +++ b/include/asm-i386/irq.h @@ -21,8 +21,6 @@ static __inline__ int irq_canonicalize(int irq) return ((irq == 2) ? 9 : irq); } -extern void release_vm86_irqs(struct task_struct *); - #ifdef CONFIG_X86_LOCAL_APIC # define ARCH_HAS_NMI_WATCHDOG /* See include/linux/nmi.h */ #endif diff --git a/include/asm-i386/vm86.h b/include/asm-i386/vm86.h index 40ec82c6914d..952fd6957380 100644 --- a/include/asm-i386/vm86.h +++ b/include/asm-i386/vm86.h @@ -16,7 +16,11 @@ #define IF_MASK 0x00000200 #define IOPL_MASK 0x00003000 #define NT_MASK 0x00004000 +#ifdef CONFIG_VM86 #define VM_MASK 0x00020000 +#else +#define VM_MASK 0 /* ignored */ +#endif #define AC_MASK 0x00040000 #define VIF_MASK 0x00080000 /* virtual interrupt flag */ #define VIP_MASK 0x00100000 /* virtual interrupt pending */ @@ -200,9 +204,25 @@ struct kernel_vm86_struct { */ }; +#ifdef CONFIG_VM86 + void handle_vm86_fault(struct kernel_vm86_regs *, long); int handle_vm86_trap(struct kernel_vm86_regs *, long, int); +struct task_struct; +void release_vm86_irqs(struct task_struct *); + +#else + +#define handle_vm86_fault(a, b) +#define release_vm86_irqs(a) + +static inline int handle_vm86_trap(struct kernel_vm86_regs *a, long b, int c) { + return 0; +} + +#endif /* CONFIG_VM86 */ + #endif /* __KERNEL__ */ #endif diff --git a/init/Kconfig b/init/Kconfig index 9ac522a40130..f8f6929d8f25 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -237,6 +237,16 @@ config UID16 help This enables the legacy 16-bit UID syscall wrappers. +config VM86 + depends X86 + default y + bool "Enable VM86 support" if EMBEDDED + help + This option is required by programs like DOSEMU to run 16-bit legacy + code on X86 processors. It also may be needed by software like + XFree86 to initialize some video cards via BIOS. Disabling this + option saves about 6k. + config CC_OPTIMIZE_FOR_SIZE bool "Optimize for size (Look out for broken compilers!)" default y diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c index 72cafc922d39..bd3b9bfcfcec 100644 --- a/kernel/sys_ni.c +++ b/kernel/sys_ni.c @@ -102,6 +102,8 @@ cond_syscall(sys_setresgid16); cond_syscall(sys_setresuid16); cond_syscall(sys_setreuid16); cond_syscall(sys_setuid16); +cond_syscall(sys_vm86old); +cond_syscall(sys_vm86); /* arch-specific weak syscall entries */ cond_syscall(sys_pciconfig_read); -- GitLab