1/*
2 * Written 2000,2002 by Andi Kleen.
3 *
4 * Losely based on the sparc64 and IA64 32bit emulation loaders.
5 * This tricks binfmt_elf.c into loading 32bit binaries using lots
6 * of ugly preprocessor tricks. Talk about very very poor man's inheritance.
7 */
8#include <linux/types.h>
9#include <linux/config.h>
10#include <linux/stddef.h>
11#include <linux/module.h>
12#include <linux/rwsem.h>
13#include <linux/sched.h>
14#include <linux/string.h>
15#include <asm/segment.h>
16#include <asm/ptrace.h>
17#include <asm/processor.h>
18#include <asm/user32.h>
19#include <asm/sigcontext32.h>
20#include <asm/fpu32.h>
21#include <asm/i387.h>
22
23struct file;
24struct elf_phdr;
25
26#define IA32_EMULATOR 1
27
28#define IA32_PAGE_OFFSET 0xFFFFF000
29#define IA32_STACK_TOP IA32_PAGE_OFFSET
30#define ELF_ET_DYN_BASE		(IA32_PAGE_OFFSET/3 + 0x1000000)
31
32#undef ELF_ARCH
33#define ELF_ARCH EM_386
34
35#undef ELF_CLASS
36#define ELF_CLASS ELFCLASS32
37
38#define ELF_DATA	ELFDATA2LSB
39
40#define USE_ELF_CORE_DUMP 1
41
42/* Overwrite elfcore.h */
43#define _LINUX_ELFCORE_H 1
44typedef unsigned int elf_greg_t;
45
46#define ELF_NGREG (sizeof (struct user_regs_struct32) / sizeof(elf_greg_t))
47typedef elf_greg_t elf_gregset_t[ELF_NGREG];
48
49struct elf_siginfo
50{
51	int	si_signo;			/* signal number */
52	int	si_code;			/* extra code */
53	int	si_errno;			/* errno */
54};
55
56struct timeval32
57{
58    int tv_sec, tv_usec;
59};
60
61struct elf_prstatus
62{
63	struct elf_siginfo pr_info;	/* Info associated with signal */
64	short	pr_cursig;		/* Current signal */
65	unsigned int pr_sigpend;	/* Set of pending signals */
66	unsigned int pr_sighold;	/* Set of held signals */
67	pid_t	pr_pid;
68	pid_t	pr_ppid;
69	pid_t	pr_pgrp;
70	pid_t	pr_sid;
71	struct timeval32 pr_utime;	/* User time */
72	struct timeval32 pr_stime;	/* System time */
73	struct timeval32 pr_cutime;	/* Cumulative user time */
74	struct timeval32 pr_cstime;	/* Cumulative system time */
75	elf_gregset_t pr_reg;	/* GP registers */
76	int pr_fpvalid;		/* True if math co-processor being used.  */
77};
78
79#define ELF_PRARGSZ	(80)	/* Number of chars for args */
80
81struct elf_prpsinfo
82{
83	char	pr_state;	/* numeric process state */
84	char	pr_sname;	/* char for pr_state */
85	char	pr_zomb;	/* zombie */
86	char	pr_nice;	/* nice val */
87	unsigned int pr_flag;	/* flags */
88	__u16	pr_uid;
89	__u16	pr_gid;
90	pid_t	pr_pid, pr_ppid, pr_pgrp, pr_sid;
91	/* Lots missing */
92	char	pr_fname[16];	/* filename of executable */
93	char	pr_psargs[ELF_PRARGSZ];	/* initial part of arg list */
94};
95
96#define __STR(x) #x
97#define STR(x) __STR(x)
98
99#define _GET_SEG(x) \
100	({ __u32 seg; asm("movl %%" STR(x) ",%0" : "=r"(seg)); seg; })
101
102/* Assumes current==process to be dumped */
103#define ELF_CORE_COPY_REGS(pr_reg, regs)       		\
104	pr_reg[0] = regs->rbx;				\
105	pr_reg[1] = regs->rcx;				\
106	pr_reg[2] = regs->rdx;				\
107	pr_reg[3] = regs->rsi;				\
108	pr_reg[4] = regs->rdi;				\
109	pr_reg[5] = regs->rbp;				\
110	pr_reg[6] = regs->rax;				\
111	pr_reg[7] = _GET_SEG(ds);   			\
112	pr_reg[8] = _GET_SEG(es);			\
113	pr_reg[9] = _GET_SEG(fs);			\
114	pr_reg[10] = _GET_SEG(gs);			\
115	pr_reg[11] = regs->orig_rax;			\
116	pr_reg[12] = regs->rip;				\
117	pr_reg[13] = regs->cs;				\
118	pr_reg[14] = regs->eflags;			\
119	pr_reg[15] = regs->rsp;				\
120	pr_reg[16] = regs->ss;
121
122#define user user32
123
124#define dump_fpu dump_fpu_ia32
125
126#define __ASM_X86_64_ELF_H 1
127#include <asm/ia32.h>
128#include <linux/elf.h>
129
130typedef struct user_i387_ia32_struct elf_fpregset_t;
131typedef struct user32_fxsr_struct elf_fpxregset_t;
132
133#undef elf_check_arch
134#define elf_check_arch(x) \
135	((x)->e_machine == EM_386)
136
137#define ELF_EXEC_PAGESIZE PAGE_SIZE
138#define ELF_HWCAP (boot_cpu_data.x86_capability[0])
139#define ELF_PLATFORM  ("i686")
140#define SET_PERSONALITY(ex, ibcs2)			\
141do {							\
142	set_personality((ibcs2)?PER_SVR4:current->personality);	\
143} while (0)
144
145/* Override some function names */
146#define elf_format			elf32_format
147
148#define init_elf_binfmt			init_elf32_binfmt
149#define exit_elf_binfmt			exit_elf32_binfmt
150
151#define load_elf_binary load_elf32_binary
152
153#undef CONFIG_BINFMT_ELF
154#ifdef CONFIG_BINFMT_ELF32
155# define CONFIG_BINFMT_ELF		CONFIG_BINFMT_ELF32
156#endif
157
158#undef CONFIG_BINFMT_ELF_MODULE
159#ifdef CONFIG_BINFMT_ELF32_MODULE
160# define CONFIG_BINFMT_ELF_MODULE	CONFIG_BINFMT_ELF32_MODULE
161#endif
162
163#define ELF_PLAT_INIT(r)		elf32_init(r)
164#define setup_arg_pages(bprm)		ia32_setup_arg_pages(bprm)
165
166#undef start_thread
167#define start_thread(regs,new_rip,new_rsp) do { \
168	__asm__("movl %0,%%fs": :"r" (0)); \
169	__asm__("movl %0,%%es; movl %0,%%ds": :"r" (__USER32_DS)); \
170	wrmsrl(MSR_KERNEL_GS_BASE, 0); \
171	(regs)->rip = (new_rip); \
172	(regs)->rsp = (new_rsp); \
173	(regs)->eflags = 0x200; \
174	(regs)->cs = __USER32_CS; \
175	(regs)->ss = __USER32_DS; \
176	set_fs(USER_DS); \
177} while(0)
178
179
180#define elf_map elf32_map
181
182MODULE_DESCRIPTION("Binary format loader for compatibility with IA32 ELF binaries.");
183MODULE_AUTHOR("Eric Youngdale, Andi Kleen");
184
185#undef MODULE_DESCRIPTION
186#undef MODULE_AUTHOR
187
188#define elf_addr_t __u32
189#define elf_caddr_t __u32
190
191static void elf32_init(struct pt_regs *);
192int ia32_setup_arg_pages(struct linux_binprm *bprm);
193
194#include "../../../fs/binfmt_elf.c"
195
196static void elf32_init(struct pt_regs *regs)
197{
198	struct task_struct *me = current;
199	regs->rdi = 0;
200	regs->rsi = 0;
201	regs->rdx = 0;
202	regs->rcx = 0;
203	regs->rax = 0;
204	regs->rbx = 0;
205	regs->rbp = 0;
206	me->thread.fs = 0;
207	me->thread.gs = 0;
208	me->thread.fsindex = 0;
209	me->thread.gsindex = 0;
210	me->thread.ds = __USER_DS;
211	me->thread.es = __USER_DS;
212	me->thread.flags |= THREAD_IA32;
213}
214
215extern void put_dirty_page(struct task_struct * tsk, struct page *page, unsigned long address);
216
217
218int ia32_setup_arg_pages(struct linux_binprm *bprm)
219{
220	unsigned long stack_base;
221	struct vm_area_struct *mpnt;
222	int i;
223
224	stack_base = IA32_STACK_TOP - MAX_ARG_PAGES*PAGE_SIZE;
225
226	bprm->p += stack_base;
227	if (bprm->loader)
228		bprm->loader += stack_base;
229	bprm->exec += stack_base;
230
231	mpnt = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
232	if (!mpnt)
233		return -ENOMEM;
234
235	down_write(&current->mm->mmap_sem);
236	{
237		mpnt->vm_mm = current->mm;
238		mpnt->vm_start = PAGE_MASK & (unsigned long) bprm->p;
239		mpnt->vm_end = IA32_STACK_TOP;
240		mpnt->vm_page_prot = PAGE_COPY;
241		mpnt->vm_flags = VM_STACK_FLAGS;
242		mpnt->vm_ops = NULL;
243		mpnt->vm_pgoff = 0;
244		mpnt->vm_file = NULL;
245		mpnt->vm_private_data = (void *) 0;
246		insert_vm_struct(current->mm, mpnt);
247		current->mm->total_vm = (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT;
248	}
249
250	for (i = 0 ; i < MAX_ARG_PAGES ; i++) {
251		struct page *page = bprm->page[i];
252		if (page) {
253			bprm->page[i] = NULL;
254			current->mm->rss++;
255			put_dirty_page(current,page,stack_base);
256		}
257		stack_base += PAGE_SIZE;
258	}
259	up_write(&current->mm->mmap_sem);
260
261	return 0;
262}
263static unsigned long
264elf32_map (struct file *filep, unsigned long addr, struct elf_phdr *eppnt, int prot, int type)
265{
266	unsigned long map_addr;
267	struct task_struct *me = current;
268
269	if (prot & PROT_READ)
270		prot |= PROT_EXEC;
271
272	down_write(&me->mm->mmap_sem);
273	map_addr = do_mmap(filep, ELF_PAGESTART(addr),
274			   eppnt->p_filesz + ELF_PAGEOFFSET(eppnt->p_vaddr), prot,
275			   type|MAP_32BIT,
276			   eppnt->p_offset - ELF_PAGEOFFSET(eppnt->p_vaddr));
277	up_write(&me->mm->mmap_sem);
278	return(map_addr);
279}
280
281int dump_fpu_ia32(struct pt_regs *regs, elf_fpregset_t *fp)
282{
283	struct _fpstate_ia32 *fpu = (void*)fp;
284	struct task_struct *tsk = current;
285	mm_segment_t oldfs = get_fs();
286	int ret;
287
288	if (!tsk->used_math)
289		return 0;
290	if (!(tsk->thread.flags & THREAD_IA32))
291		BUG();
292	unlazy_fpu(tsk);
293	set_fs(KERNEL_DS);
294	ret = save_i387_ia32(current, fpu, regs, 1);
295	/* Correct for i386 bug. It puts the fop into the upper 16bits of
296	   the tag word (like FXSAVE), not into the fcs*/
297	fpu->cssel |= fpu->tag & 0xffff0000;
298	set_fs(oldfs);
299	return ret;
300}
301