diff options
Diffstat (limited to 'arch/ia64/ia32/ia32_support.c')
| -rw-r--r-- | arch/ia64/ia32/ia32_support.c | 264 |
1 files changed, 264 insertions, 0 deletions
diff --git a/arch/ia64/ia32/ia32_support.c b/arch/ia64/ia32/ia32_support.c new file mode 100644 index 00000000000..4f630043b3a --- /dev/null +++ b/arch/ia64/ia32/ia32_support.c @@ -0,0 +1,264 @@ +/* + * IA32 helper functions + * + * Copyright (C) 1999 Arun Sharma <arun.sharma@intel.com> + * Copyright (C) 2000 Asit K. Mallick <asit.k.mallick@intel.com> + * Copyright (C) 2001-2002 Hewlett-Packard Co + * David Mosberger-Tang <davidm@hpl.hp.com> + * + * 06/16/00 A. Mallick added csd/ssd/tssd for ia32 thread context + * 02/19/01 D. Mosberger dropped tssd; it's not needed + * 09/14/01 D. Mosberger fixed memory management for gdt/tss page + * 09/29/01 D. Mosberger added ia32_load_segment_descriptors() + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/mm.h> +#include <linux/personality.h> +#include <linux/sched.h> + +#include <asm/intrinsics.h> +#include <asm/page.h> +#include <asm/pgtable.h> +#include <asm/system.h> +#include <asm/processor.h> +#include <asm/uaccess.h> + +#include "ia32priv.h" + +extern void die_if_kernel (char *str, struct pt_regs *regs, long err); + +struct exec_domain ia32_exec_domain; +struct page *ia32_shared_page[NR_CPUS]; +unsigned long *ia32_boot_gdt; +unsigned long *cpu_gdt_table[NR_CPUS]; +struct page *ia32_gate_page; + +static unsigned long +load_desc (u16 selector) +{ + unsigned long *table, limit, index; + + if (!selector) + return 0; + if (selector & IA32_SEGSEL_TI) { + table = (unsigned long *) IA32_LDT_OFFSET; + limit = IA32_LDT_ENTRIES; + } else { + table = cpu_gdt_table[smp_processor_id()]; + limit = IA32_PAGE_SIZE / sizeof(ia32_boot_gdt[0]); + } + index = selector >> IA32_SEGSEL_INDEX_SHIFT; + if (index >= limit) + return 0; + return IA32_SEG_UNSCRAMBLE(table[index]); +} + +void +ia32_load_segment_descriptors (struct task_struct *task) +{ + struct pt_regs *regs = ia64_task_regs(task); + + /* Setup the segment descriptors */ + regs->r24 = load_desc(regs->r16 >> 16); /* ESD */ + regs->r27 = load_desc(regs->r16 >> 0); /* DSD */ + regs->r28 = load_desc(regs->r16 >> 32); /* FSD */ + regs->r29 = load_desc(regs->r16 >> 48); /* GSD */ + regs->ar_csd = load_desc(regs->r17 >> 0); /* CSD */ + regs->ar_ssd = load_desc(regs->r17 >> 16); /* SSD */ +} + +int +ia32_clone_tls (struct task_struct *child, struct pt_regs *childregs) +{ + struct desc_struct *desc; + struct ia32_user_desc info; + int idx; + + if (copy_from_user(&info, (void __user *)(childregs->r14 & 0xffffffff), sizeof(info))) + return -EFAULT; + if (LDT_empty(&info)) + return -EINVAL; + + idx = info.entry_number; + if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX) + return -EINVAL; + + desc = child->thread.tls_array + idx - GDT_ENTRY_TLS_MIN; + desc->a = LDT_entry_a(&info); + desc->b = LDT_entry_b(&info); + + /* XXX: can this be done in a cleaner way ? */ + load_TLS(&child->thread, smp_processor_id()); + ia32_load_segment_descriptors(child); + load_TLS(¤t->thread, smp_processor_id()); + + return 0; +} + +void +ia32_save_state (struct task_struct *t) +{ + t->thread.eflag = ia64_getreg(_IA64_REG_AR_EFLAG); + t->thread.fsr = ia64_getreg(_IA64_REG_AR_FSR); + t->thread.fcr = ia64_getreg(_IA64_REG_AR_FCR); + t->thread.fir = ia64_getreg(_IA64_REG_AR_FIR); + t->thread.fdr = ia64_getreg(_IA64_REG_AR_FDR); + ia64_set_kr(IA64_KR_IO_BASE, t->thread.old_iob); + ia64_set_kr(IA64_KR_TSSD, t->thread.old_k1); +} + +void +ia32_load_state (struct task_struct *t) +{ + unsigned long eflag, fsr, fcr, fir, fdr, tssd; + struct pt_regs *regs = ia64_task_regs(t); + + eflag = t->thread.eflag; + fsr = t->thread.fsr; + fcr = t->thread.fcr; + fir = t->thread.fir; + fdr = t->thread.fdr; + tssd = load_desc(_TSS); /* TSSD */ + + ia64_setreg(_IA64_REG_AR_EFLAG, eflag); + ia64_setreg(_IA64_REG_AR_FSR, fsr); + ia64_setreg(_IA64_REG_AR_FCR, fcr); + ia64_setreg(_IA64_REG_AR_FIR, fir); + ia64_setreg(_IA64_REG_AR_FDR, fdr); + current->thread.old_iob = ia64_get_kr(IA64_KR_IO_BASE); + current->thread.old_k1 = ia64_get_kr(IA64_KR_TSSD); + ia64_set_kr(IA64_KR_IO_BASE, IA32_IOBASE); + ia64_set_kr(IA64_KR_TSSD, tssd); + + regs->r17 = (_TSS << 48) | (_LDT << 32) | (__u32) regs->r17; + regs->r30 = load_desc(_LDT); /* LDTD */ + load_TLS(&t->thread, smp_processor_id()); +} + +/* + * Setup IA32 GDT and TSS + */ +void +ia32_gdt_init (void) +{ + int cpu = smp_processor_id(); + + ia32_shared_page[cpu] = alloc_page(GFP_KERNEL); + if (!ia32_shared_page[cpu]) + panic("failed to allocate ia32_shared_page[%d]\n", cpu); + + cpu_gdt_table[cpu] = page_address(ia32_shared_page[cpu]); + + /* Copy from the boot cpu's GDT */ + memcpy(cpu_gdt_table[cpu], ia32_boot_gdt, PAGE_SIZE); +} + + +/* + * Setup IA32 GDT and TSS + */ +static void +ia32_boot_gdt_init (void) +{ + unsigned long ldt_size; + + ia32_shared_page[0] = alloc_page(GFP_KERNEL); + if (!ia32_shared_page[0]) + panic("failed to allocate ia32_shared_page[0]\n"); + + ia32_boot_gdt = page_address(ia32_shared_page[0]); + cpu_gdt_table[0] = ia32_boot_gdt; + + /* CS descriptor in IA-32 (scrambled) format */ + ia32_boot_gdt[__USER_CS >> 3] + = IA32_SEG_DESCRIPTOR(0, (IA32_GATE_END-1) >> IA32_PAGE_SHIFT, + 0xb, 1, 3, 1, 1, 1, 1); + + /* DS descriptor in IA-32 (scrambled) format */ + ia32_boot_gdt[__USER_DS >> 3] + = IA32_SEG_DESCRIPTOR(0, (IA32_GATE_END-1) >> IA32_PAGE_SHIFT, + 0x3, 1, 3, 1, 1, 1, 1); + + ldt_size = PAGE_ALIGN(IA32_LDT_ENTRIES*IA32_LDT_ENTRY_SIZE); + ia32_boot_gdt[TSS_ENTRY] = IA32_SEG_DESCRIPTOR(IA32_TSS_OFFSET, 235, + 0xb, 0, 3, 1, 1, 1, 0); + ia32_boot_gdt[LDT_ENTRY] = IA32_SEG_DESCRIPTOR(IA32_LDT_OFFSET, ldt_size - 1, + 0x2, 0, 3, 1, 1, 1, 0); +} + +static void +ia32_gate_page_init(void) +{ + unsigned long *sr; + + ia32_gate_page = alloc_page(GFP_KERNEL); + sr = page_address(ia32_gate_page); + /* This is popl %eax ; movl $,%eax ; int $0x80 */ + *sr++ = 0xb858 | (__IA32_NR_sigreturn << 16) | (0x80cdUL << 48); + + /* This is movl $,%eax ; int $0x80 */ + *sr = 0xb8 | (__IA32_NR_rt_sigreturn << 8) | (0x80cdUL << 40); +} + +void +ia32_mem_init(void) +{ + ia32_boot_gdt_init(); + ia32_gate_page_init(); +} + +/* + * Handle bad IA32 interrupt via syscall + */ +void +ia32_bad_interrupt (unsigned long int_num, struct pt_regs *regs) +{ + siginfo_t siginfo; + + die_if_kernel("Bad IA-32 interrupt", regs, int_num); + + siginfo.si_signo = SIGTRAP; + siginfo.si_errno = int_num; /* XXX is it OK to abuse si_errno like this? */ + siginfo.si_flags = 0; + siginfo.si_isr = 0; + siginfo.si_addr = NULL; + siginfo.si_imm = 0; + siginfo.si_code = TRAP_BRKPT; + force_sig_info(SIGTRAP, &siginfo, current); +} + +void +ia32_cpu_init (void) +{ + /* initialize global ia32 state - CR0 and CR4 */ + ia64_setreg(_IA64_REG_AR_CFLAG, (((ulong) IA32_CR4 << 32) | IA32_CR0)); +} + +static int __init +ia32_init (void) +{ + ia32_exec_domain.name = "Linux/x86"; + ia32_exec_domain.handler = NULL; + ia32_exec_domain.pers_low = PER_LINUX32; + ia32_exec_domain.pers_high = PER_LINUX32; + ia32_exec_domain.signal_map = default_exec_domain.signal_map; + ia32_exec_domain.signal_invmap = default_exec_domain.signal_invmap; + register_exec_domain(&ia32_exec_domain); + +#if PAGE_SHIFT > IA32_PAGE_SHIFT + { + extern kmem_cache_t *partial_page_cachep; + + partial_page_cachep = kmem_cache_create("partial_page_cache", + sizeof(struct partial_page), 0, 0, + NULL, NULL); + if (!partial_page_cachep) + panic("Cannot create partial page SLAB cache"); + } +#endif + return 0; +} + +__initcall(ia32_init); |