diff options
Diffstat (limited to 'arch/ia64/kernel/unwind.c')
| -rw-r--r-- | arch/ia64/kernel/unwind.c | 2306 |
1 files changed, 2306 insertions, 0 deletions
diff --git a/arch/ia64/kernel/unwind.c b/arch/ia64/kernel/unwind.c new file mode 100644 index 00000000000..d494ff647ca --- /dev/null +++ b/arch/ia64/kernel/unwind.c @@ -0,0 +1,2306 @@ +/* + * Copyright (C) 1999-2004 Hewlett-Packard Co + * David Mosberger-Tang <davidm@hpl.hp.com> + * Copyright (C) 2003 Fenghua Yu <fenghua.yu@intel.com> + * - Change pt_regs_off() to make it less dependant on pt_regs structure. + */ +/* + * This file implements call frame unwind support for the Linux + * kernel. Parsing and processing the unwind information is + * time-consuming, so this implementation translates the unwind + * descriptors into unwind scripts. These scripts are very simple + * (basically a sequence of assignments) and efficient to execute. + * They are cached for later re-use. Each script is specific for a + * given instruction pointer address and the set of predicate values + * that the script depends on (most unwind descriptors are + * unconditional and scripts often do not depend on predicates at + * all). This code is based on the unwind conventions described in + * the "IA-64 Software Conventions and Runtime Architecture" manual. + * + * SMP conventions: + * o updates to the global unwind data (in structure "unw") are serialized + * by the unw.lock spinlock + * o each unwind script has its own read-write lock; a thread must acquire + * a read lock before executing a script and must acquire a write lock + * before modifying a script + * o if both the unw.lock spinlock and a script's read-write lock must be + * acquired, then the read-write lock must be acquired first. + */ +#include <linux/module.h> +#include <linux/bootmem.h> +#include <linux/elf.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/slab.h> + +#include <asm/unwind.h> + +#include <asm/delay.h> +#include <asm/page.h> +#include <asm/ptrace.h> +#include <asm/ptrace_offsets.h> +#include <asm/rse.h> +#include <asm/sections.h> +#include <asm/system.h> +#include <asm/uaccess.h> + +#include "entry.h" +#include "unwind_i.h" + +#define UNW_LOG_CACHE_SIZE 7 /* each unw_script is ~256 bytes in size */ +#define UNW_CACHE_SIZE (1 << UNW_LOG_CACHE_SIZE) + +#define UNW_LOG_HASH_SIZE (UNW_LOG_CACHE_SIZE + 1) +#define UNW_HASH_SIZE (1 << UNW_LOG_HASH_SIZE) + +#define UNW_STATS 0 /* WARNING: this disabled interrupts for long time-spans!! */ + +#ifdef UNW_DEBUG + static unsigned int unw_debug_level = UNW_DEBUG; +# define UNW_DEBUG_ON(n) unw_debug_level >= n + /* Do not code a printk level, not all debug lines end in newline */ +# define UNW_DPRINT(n, ...) if (UNW_DEBUG_ON(n)) printk(__VA_ARGS__) +# define inline +#else /* !UNW_DEBUG */ +# define UNW_DEBUG_ON(n) 0 +# define UNW_DPRINT(n, ...) +#endif /* UNW_DEBUG */ + +#if UNW_STATS +# define STAT(x...) x +#else +# define STAT(x...) +#endif + +#define alloc_reg_state() kmalloc(sizeof(struct unw_reg_state), GFP_ATOMIC) +#define free_reg_state(usr) kfree(usr) +#define alloc_labeled_state() kmalloc(sizeof(struct unw_labeled_state), GFP_ATOMIC) +#define free_labeled_state(usr) kfree(usr) + +typedef unsigned long unw_word; +typedef unsigned char unw_hash_index_t; + +static struct { + spinlock_t lock; /* spinlock for unwind data */ + + /* list of unwind tables (one per load-module) */ + struct unw_table *tables; + + unsigned long r0; /* constant 0 for r0 */ + + /* table of registers that prologues can save (and order in which they're saved): */ + const unsigned char save_order[8]; + + /* maps a preserved register index (preg_index) to corresponding switch_stack offset: */ + unsigned short sw_off[sizeof(struct unw_frame_info) / 8]; + + unsigned short lru_head; /* index of lead-recently used script */ + unsigned short lru_tail; /* index of most-recently used script */ + + /* index into unw_frame_info for preserved register i */ + unsigned short preg_index[UNW_NUM_REGS]; + + short pt_regs_offsets[32]; + + /* unwind table for the kernel: */ + struct unw_table kernel_table; + + /* unwind table describing the gate page (kernel code that is mapped into user space): */ + size_t gate_table_size; + unsigned long *gate_table; + + /* hash table that maps instruction pointer to script index: */ + unsigned short hash[UNW_HASH_SIZE]; + + /* script cache: */ + struct unw_script cache[UNW_CACHE_SIZE]; + +# ifdef UNW_DEBUG + const char *preg_name[UNW_NUM_REGS]; +# endif +# if UNW_STATS + struct { + struct { + int lookups; + int hinted_hits; + int normal_hits; + int collision_chain_traversals; + } cache; + struct { + unsigned long build_time; + unsigned long run_time; + unsigned long parse_time; + int builds; + int news; + int collisions; + int runs; + } script; + struct { + unsigned long init_time; + unsigned long unwind_time; + int inits; + int unwinds; + } api; + } stat; +# endif +} unw = { + .tables = &unw.kernel_table, + .lock = SPIN_LOCK_UNLOCKED, + .save_order = { + UNW_REG_RP, UNW_REG_PFS, UNW_REG_PSP, UNW_REG_PR, + UNW_REG_UNAT, UNW_REG_LC, UNW_REG_FPSR, UNW_REG_PRI_UNAT_GR + }, + .preg_index = { + offsetof(struct unw_frame_info, pri_unat_loc)/8, /* PRI_UNAT_GR */ + offsetof(struct unw_frame_info, pri_unat_loc)/8, /* PRI_UNAT_MEM */ + offsetof(struct unw_frame_info, bsp_loc)/8, + offsetof(struct unw_frame_info, bspstore_loc)/8, + offsetof(struct unw_frame_info, pfs_loc)/8, + offsetof(struct unw_frame_info, rnat_loc)/8, + offsetof(struct unw_frame_info, psp)/8, + offsetof(struct unw_frame_info, rp_loc)/8, + offsetof(struct unw_frame_info, r4)/8, + offsetof(struct unw_frame_info, r5)/8, + offsetof(struct unw_frame_info, r6)/8, + offsetof(struct unw_frame_info, r7)/8, + offsetof(struct unw_frame_info, unat_loc)/8, + offsetof(struct unw_frame_info, pr_loc)/8, + offsetof(struct unw_frame_info, lc_loc)/8, + offsetof(struct unw_frame_info, fpsr_loc)/8, + offsetof(struct unw_frame_info, b1_loc)/8, + offsetof(struct unw_frame_info, b2_loc)/8, + offsetof(struct unw_frame_info, b3_loc)/8, + offsetof(struct unw_frame_info, b4_loc)/8, + offsetof(struct unw_frame_info, b5_loc)/8, + offsetof(struct unw_frame_info, f2_loc)/8, + offsetof(struct unw_frame_info, f3_loc)/8, + offsetof(struct unw_frame_info, f4_loc)/8, + offsetof(struct unw_frame_info, f5_loc)/8, + offsetof(struct unw_frame_info, fr_loc[16 - 16])/8, + offsetof(struct unw_frame_info, fr_loc[17 - 16])/8, + offsetof(struct unw_frame_info, fr_loc[18 - 16])/8, + offsetof(struct unw_frame_info, fr_loc[19 - 16])/8, + offsetof(struct unw_frame_info, fr_loc[20 - 16])/8, + offsetof(struct unw_frame_info, fr_loc[21 - 16])/8, + offsetof(struct unw_frame_info, fr_loc[22 - 16])/8, + offsetof(struct unw_frame_info, fr_loc[23 - 16])/8, + offsetof(struct unw_frame_info, fr_loc[24 - 16])/8, + offsetof(struct unw_frame_info, fr_loc[25 - 16])/8, + offsetof(struct unw_frame_info, fr_loc[26 - 16])/8, + offsetof(struct unw_frame_info, fr_loc[27 - 16])/8, + offsetof(struct unw_frame_info, fr_loc[28 - 16])/8, + offsetof(struct unw_frame_info, fr_loc[29 - 16])/8, + offsetof(struct unw_frame_info, fr_loc[30 - 16])/8, + offsetof(struct unw_frame_info, fr_loc[31 - 16])/8, + }, + .pt_regs_offsets = { + [0] = -1, + offsetof(struct pt_regs, r1), + offsetof(struct pt_regs, r2), + offsetof(struct pt_regs, r3), + [4] = -1, [5] = -1, [6] = -1, [7] = -1, + offsetof(struct pt_regs, r8), + offsetof(struct pt_regs, r9), + offsetof(struct pt_regs, r10), + offsetof(struct pt_regs, r11), + offsetof(struct pt_regs, r12), + offsetof(struct pt_regs, r13), + offsetof(struct pt_regs, r14), + offsetof(struct pt_regs, r15), + offsetof(struct pt_regs, r16), + offsetof(struct pt_regs, r17), + offsetof(struct pt_regs, r18), + offsetof(struct pt_regs, r19), + offsetof(struct pt_regs, r20), + offsetof(struct pt_regs, r21), + offsetof(struct pt_regs, r22), + offsetof(struct pt_regs, r23), + offsetof(struct pt_regs, r24), + offsetof(struct pt_regs, r25), + offsetof(struct pt_regs, r26), + offsetof(struct pt_regs, r27), + offsetof(struct pt_regs, r28), + offsetof(struct pt_regs, r29), + offsetof(struct pt_regs, r30), + offsetof(struct pt_regs, r31), + }, + .hash = { [0 ... UNW_HASH_SIZE - 1] = -1 }, +#ifdef UNW_DEBUG + .preg_name = { + "pri_unat_gr", "pri_unat_mem", "bsp", "bspstore", "ar.pfs", "ar.rnat", "psp", "rp", + "r4", "r5", "r6", "r7", + "ar.unat", "pr", "ar.lc", "ar.fpsr", + "b1", "b2", "b3", "b4", "b5", + "f2", "f3", "f4", "f5", + "f16", "f17", "f18", "f19", "f20", "f21", "f22", "f23", + "f24", "f25", "f26", "f27", "f28", "f29", "f30", "f31" + } +#endif +}; + +static inline int +read_only (void *addr) +{ + return (unsigned long) ((char *) addr - (char *) &unw.r0) < sizeof(unw.r0); +} + +/* + * Returns offset of rREG in struct pt_regs. + */ +static inline unsigned long +pt_regs_off (unsigned long reg) +{ + short off = -1; + + if (reg < ARRAY_SIZE(unw.pt_regs_offsets)) + off = unw.pt_regs_offsets[reg]; + + if (off < 0) { + UNW_DPRINT(0, "unwind.%s: bad scratch reg r%lu\n", __FUNCTION__, reg); + off = 0; + } + return (unsigned long) off; +} + +static inline struct pt_regs * +get_scratch_regs (struct unw_frame_info *info) +{ + if (!info->pt) { + /* This should not happen with valid unwind info. */ + UNW_DPRINT(0, "unwind.%s: bad unwind info: resetting info->pt\n", __FUNCTION__); + if (info->flags & UNW_FLAG_INTERRUPT_FRAME) + info->pt = (unsigned long) ((struct pt_regs *) info->psp - 1); + else + info->pt = info->sp - 16; + } + UNW_DPRINT(3, "unwind.%s: sp 0x%lx pt 0x%lx\n", __FUNCTION__, info->sp, info->pt); + return (struct pt_regs *) info->pt; +} + +/* Unwind accessors. */ + +int +unw_access_gr (struct unw_frame_info *info, int regnum, unsigned long *val, char *nat, int write) +{ + unsigned long *addr, *nat_addr, nat_mask = 0, dummy_nat; + struct unw_ireg *ireg; + struct pt_regs *pt; + + if ((unsigned) regnum - 1 >= 127) { + if (regnum == 0 && !write) { + *val = 0; /* read r0 always returns 0 */ + *nat = 0; + return 0; + } + UNW_DPRINT(0, "unwind.%s: trying to access non-existent r%u\n", + __FUNCTION__, regnum); + return -1; + } + + if (regnum < 32) { + if (regnum >= 4 && regnum <= 7) { + /* access a preserved register */ + ireg = &info->r4 + (regnum - 4); + addr = ireg->loc; + if (addr) { + nat_addr = addr + ireg->nat.off; + switch (ireg->nat.type) { + case UNW_NAT_VAL: + /* simulate getf.sig/setf.sig */ + if (write) { + if (*nat) { + /* write NaTVal and be done with it */ + addr[0] = 0; + addr[1] = 0x1fffe; + return 0; + } + addr[1] = 0x1003e; + } else { + if (addr[0] == 0 && addr[1] == 0x1ffe) { + /* return NaT and be done with it */ + *val = 0; + *nat = 1; + return 0; + } + } + /* fall through */ + case UNW_NAT_NONE: + dummy_nat = 0; + nat_addr = &dummy_nat; + break; + + case UNW_NAT_MEMSTK: + nat_mask = (1UL << ((long) addr & 0x1f8)/8); + break; + + case UNW_NAT_REGSTK: + nat_addr = ia64_rse_rnat_addr(addr); + if ((unsigned long) addr < info->regstk.limit + || (unsigned long) addr >= info->regstk.top) + { + UNW_DPRINT(0, "unwind.%s: %p outside of regstk " + "[0x%lx-0x%lx)\n", + __FUNCTION__, (void *) addr, + info->regstk.limit, + info->regstk.top); + return -1; + } + if ((unsigned long) nat_addr >= info->regstk.top) + nat_addr = &info->sw->ar_rnat; + nat_mask = (1UL << ia64_rse_slot_num(addr)); + break; + } + } else { + addr = &info->sw->r4 + (regnum - 4); + nat_addr = &info->sw->ar_unat; + nat_mask = (1UL << ((long) addr & 0x1f8)/8); + } + } else { + /* access a scratch register */ + pt = get_scratch_regs(info); + addr = (unsigned long *) ((unsigned long)pt + pt_regs_off(regnum)); + if (info->pri_unat_loc) + nat_addr = info->pri_unat_loc; + else + nat_addr = &info->sw->ar_unat; + nat_mask = (1UL << ((long) addr & 0x1f8)/8); + } + } else { + /* access a stacked register */ + addr = ia64_rse_skip_regs((unsigned long *) info->bsp, regnum - 32); + nat_addr = ia64_rse_rnat_addr(addr); + if ((unsigned long) addr < info->regstk.limit + || (unsigned long) addr >= info->regstk.top) + { + UNW_DPRINT(0, "unwind.%s: ignoring attempt to access register outside " + "of rbs\n", __FUNCTION__); + return -1; + } + if ((unsigned long) nat_addr >= info->regstk.top) + nat_addr = &info->sw->ar_rnat; + nat_mask = (1UL << ia64_rse_slot_num(addr)); + } + + if (write) { + if (read_only(addr)) { + UNW_DPRINT(0, "unwind.%s: ignoring attempt to write read-only location\n", + __FUNCTION__); + } else { + *addr = *val; + if (*nat) + *nat_addr |= nat_mask; + else + *nat_addr &= ~nat_mask; + } + } else { + if ((*nat_addr & nat_mask) == 0) { + *val = *addr; + *nat = 0; + } else { + *val = 0; /* if register is a NaT, *addr may contain kernel data! */ + *nat = 1; + } + } + return 0; +} +EXPORT_SYMBOL(unw_access_gr); + +int +unw_access_br (struct unw_frame_info *info, int regnum, unsigned long *val, int write) +{ + unsigned long *addr; + struct pt_regs *pt; + + switch (regnum) { + /* scratch: */ + case 0: pt = get_scratch_regs(info); addr = &pt->b0; break; + case 6: pt = get_scratch_regs(info); addr = &pt->b6; break; + case 7: pt = get_scratch_regs(info); addr = &pt->b7; break; + + /* preserved: */ + case 1: case 2: case 3: case 4: case 5: + addr = *(&info->b1_loc + (regnum - 1)); + if (!addr) + addr = &info->sw->b1 + (regnum - 1); + break; + + default: + UNW_DPRINT(0, "unwind.%s: trying to access non-existent b%u\n", + __FUNCTION__, regnum); + return -1; + } + if (write) + if (read_only(addr)) { + UNW_DPRINT(0, "unwind.%s: ignoring attempt to write read-only location\n", + __FUNCTION__); + } else + *addr = *val; + else + *val = *addr; + return 0; +} +EXPORT_SYMBOL(unw_access_br); + +int +unw_access_fr (struct unw_frame_info *info, int regnum, struct ia64_fpreg *val, int write) +{ + struct ia64_fpreg *addr = NULL; + struct pt_regs *pt; + + if ((unsigned) (regnum - 2) >= 126) { + UNW_DPRINT(0, "unwind.%s: trying to access non-existent f%u\n", + __FUNCTION__, regnum); + return -1; + } + + if (regnum <= 5) { + addr = *(&info->f2_loc + (regnum - 2)); + if (!addr) + addr = &info->sw->f2 + (regnum - 2); + } else if (regnum <= 15) { + if (regnum <= 11) { + pt = get_scratch_regs(info); + addr = &pt->f6 + (regnum - 6); + } + else + addr = &info->sw->f12 + (regnum - 12); + } else if (regnum <= 31) { + addr = info->fr_loc[regnum - 16]; + if (!addr) + addr = &info->sw->f16 + (regnum - 16); + } else { + struct task_struct *t = info->task; + + if (write) + ia64_sync_fph(t); + else + ia64_flush_fph(t); + addr = t->thread.fph + (regnum - 32); + } + + if (write) + if (read_only(addr)) { + UNW_DPRINT(0, "unwind.%s: ignoring attempt to write read-only location\n", + __FUNCTION__); + } else + *addr = *val; + else + *val = *addr; + return 0; +} +EXPORT_SYMBOL(unw_access_fr); + +int +unw_access_ar (struct unw_frame_info *info, int regnum, unsigned long *val, int write) +{ + unsigned long *addr; + struct pt_regs *pt; + + switch (regnum) { + case UNW_AR_BSP: + addr = info->bsp_loc; + if (!addr) + addr = &info->sw->ar_bspstore; + break; + + case UNW_AR_BSPSTORE: + addr = info->bspstore_loc; + if (!addr) + addr = &info->sw->ar_bspstore; + break; + + case UNW_AR_PFS: + addr = info->pfs_loc; + if (!addr) + addr = &info->sw->ar_pfs; + break; + + case UNW_AR_RNAT: + addr = info->rnat_loc; + if (!addr) + addr = &info->sw->ar_rnat; + break; + + case UNW_AR_UNAT: + addr = info->unat_loc; + if (!addr) + addr = &info->sw->ar_unat; + break; + + case UNW_AR_LC: + addr = info->lc_loc; + if (!addr) + addr = &info->sw->ar_lc; + break; + + case UNW_AR_EC: + if (!info->cfm_loc) + return -1; + if (write) + *info->cfm_loc = + (*info->cfm_loc & ~(0x3fUL << 52)) | ((*val & 0x3f) << 52); + else + *val = (*info->cfm_loc >> 52) & 0x3f; + return 0; + + case UNW_AR_FPSR: + addr = info->fpsr_loc; + if (!addr) + addr = &info->sw->ar_fpsr; + break; + + case UNW_AR_RSC: + pt = get_scratch_regs(info); + addr = &pt->ar_rsc; + break; + + case UNW_AR_CCV: + pt = get_scratch_regs(info); + addr = &pt->ar_ccv; + break; + + case UNW_AR_CSD: + pt = get_scratch_regs(info); + addr = &pt->ar_csd; + break; + + case UNW_AR_SSD: + pt = get_scratch_regs(info); + addr = &pt->ar_ssd; + break; + + default: + UNW_DPRINT(0, "unwind.%s: trying to access non-existent ar%u\n", + __FUNCTION__, regnum); + return -1; + } + + if (write) { + if (read_only(addr)) { + UNW_DPRINT(0, "unwind.%s: ignoring attempt to write read-only location\n", + __FUNCTION__); + } else + *addr = *val; + } else + *val = *addr; + return 0; +} +EXPORT_SYMBOL(unw_access_ar); + +int +unw_access_pr (struct unw_frame_info *info, unsigned long *val, int write) +{ + unsigned long *addr; + + addr = info->pr_loc; + if (!addr) + addr = &info->sw->pr; + + if (write) { + if (read_only(addr)) { + UNW_DPRINT(0, "unwind.%s: ignoring attempt to write read-only location\n", + __FUNCTION__); + } else + *addr = *val; + } else + *val = *addr; + return 0; +} +EXPORT_SYMBOL(unw_access_pr); + + +/* Routines to manipulate the state stack. */ + +static inline void +push (struct unw_state_record *sr) +{ + struct unw_reg_state *rs; + + rs = alloc_reg_state(); + if (!rs) { + printk(KERN_ERR "unwind: cannot stack reg state!\n"); + return; + } + memcpy(rs, &sr->curr, sizeof(*rs)); + sr->curr.next = rs; +} + +static void +pop (struct unw_state_record *sr) +{ + struct unw_reg_state *rs = sr->curr.next; + + if (!rs) { + printk(KERN_ERR "unwind: stack underflow!\n"); + return; + } + memcpy(&sr->curr, rs, sizeof(*rs)); + free_reg_state(rs); +} + +/* Make a copy of the state stack. Non-recursive to avoid stack overflows. */ +static struct unw_reg_state * +dup_state_stack (struct unw_reg_state *rs) +{ + struct unw_reg_state *copy, *prev = NULL, *first = NULL; + + while (rs) { + copy = alloc_reg_state(); + if (!copy) { + printk(KERN_ERR "unwind.dup_state_stack: out of memory\n"); + return NULL; + } + memcpy(copy, rs, sizeof(*copy)); + if (first) + prev->next = copy; + else + first = copy; + rs = rs->next; + prev = copy; + } + return first; +} + +/* Free all stacked register states (but not RS itself). */ +static void +free_state_stack (struct unw_reg_state *rs) +{ + struct unw_reg_state *p, *next; + + for (p = rs->next; p != NULL; p = next) { + next = p->next; + free_reg_state(p); + } + rs->next = NULL; +} + +/* Unwind decoder routines */ + +static enum unw_register_index __attribute_const__ +decode_abreg (unsigned char abreg, int memory) +{ + switch (abreg) { + case 0x04 ... 0x07: return UNW_REG_R4 + (abreg - 0x04); + case 0x22 ... 0x25: return UNW_REG_F2 + (abreg - 0x22); + case 0x30 ... 0x3f: return UNW_REG_F16 + (abreg - 0x30); + case 0x41 ... 0x45: return UNW_REG_B1 + (abreg - 0x41); + case 0x60: return UNW_REG_PR; + case 0x61: return UNW_REG_PSP; + case 0x62: return memory ? UNW_REG_PRI_UNAT_MEM : UNW_REG_PRI_UNAT_GR; + case 0x63: return UNW_REG_RP; + case 0x64: return UNW_REG_BSP; + case 0x65: return UNW_REG_BSPSTORE; + case 0x66: return UNW_REG_RNAT; + case 0x67: return UNW_REG_UNAT; + case 0x68: return UNW_REG_FPSR; + case 0x69: return UNW_REG_PFS; + case 0x6a: return UNW_REG_LC; + default: + break; + } + UNW_DPRINT(0, "unwind.%s: bad abreg=0x%x\n", __FUNCTION__, abreg); + return UNW_REG_LC; +} + +static void +set_reg (struct unw_reg_info *reg, enum unw_where where, int when, unsigned long val) +{ + reg->val = val; + reg->where = where; + if (reg->when == UNW_WHEN_NEVER) + reg->when = when; +} + +static void +alloc_spill_area (unsigned long *offp, unsigned long regsize, + struct unw_reg_info *lo, struct unw_reg_info *hi) +{ + struct unw_reg_info *reg; + + for (reg = hi; reg >= lo; --reg) { + if (reg->where == UNW_WHERE_SPILL_HOME) { + reg->where = UNW_WHERE_PSPREL; + *offp -= regsize; + reg->val = *offp; + } + } +} + +static inline void +spill_next_when (struct unw_reg_info **regp, struct unw_reg_info *lim, unw_word t) +{ + struct unw_reg_info *reg; + + for (reg = *regp; reg <= lim; ++reg) { + if (reg->where == UNW_WHERE_SPILL_HOME) { + reg->when = t; + *regp = reg + 1; + return; + } + } + UNW_DPRINT(0, "unwind.%s: excess spill!\n", __FUNCTION__); +} + +static inline void +finish_prologue (struct unw_state_record *sr) +{ + struct unw_reg_info *reg; + unsigned long off; + int i; + + /* + * First, resolve implicit register save locations (see Section "11.4.2.3 Rules + * for Using Unwind Descriptors", rule 3): + */ + for (i = 0; i < (int) ARRAY_SIZE(unw.save_order); ++i) { + reg = sr->curr.reg + unw.save_order[i]; + if (reg->where == UNW_WHERE_GR_SAVE) { + reg->where = UNW_WHERE_GR; + reg->val = sr->gr_save_loc++; + } + } + + /* + * Next, compute when the fp, general, and branch registers get + * saved. This must come before alloc_spill_area() because + * we need to know which registers are spilled to their home + * locations. + */ + if (sr->imask) { + unsigned char kind, mask = 0, *cp = sr->imask; + int t; + static const unsigned char limit[3] = { + UNW_REG_F31, UNW_REG_R7, UNW_REG_B5 + }; + struct unw_reg_info *(regs[3]); + + regs[0] = sr->curr.reg + UNW_REG_F2; + regs[1] = sr->curr.reg + UNW_REG_R4; + regs[2] = sr->curr.reg + UNW_REG_B1; + + for (t = 0; t < sr->region_len; ++t) { + if ((t & 3) == 0) + mask = *cp++; + kind = (mask >> 2*(3-(t & 3))) & 3; + if (kind > 0) + spill_next_when(®s[kind - 1], sr->curr.reg + limit[kind - 1], + sr->region_start + t); + } + } + /* + * Next, lay out the memory stack spill area: + */ + if (sr->any_spills) { + off = sr->spill_offset; + alloc_spill_area(&off, 16, sr->curr.reg + UNW_REG_F2, sr->curr.reg + UNW_REG_F31); + alloc_spill_area(&off, 8, sr->curr.reg + UNW_REG_B1, sr->curr.reg + UNW_REG_B5); + alloc_spill_area(&off, 8, sr->curr.reg + UNW_REG_R4, sr->curr.reg + UNW_REG_R7); + } +} + +/* + * Region header descriptors. + */ + +static void +desc_prologue (int body, unw_word rlen, unsigned char mask, unsigned char grsave, + struct unw_state_record *sr) +{ + int i, region_start; + + if (!(sr->in_body || sr->first_region)) + finish_prologue(sr); + sr->first_region = 0; + + /* check if we're done: */ + if (sr->when_target < sr->region_start + sr->region_len) { + sr->done = 1; + return; + } + + region_start = sr->region_start + sr->region_len; + + for (i = 0; i < sr->epilogue_count; ++i) + pop(sr); + sr->epilogue_count = 0; + sr->epilogue_start = UNW_WHEN_NEVER; + + sr->region_start = region_start; + sr->region_len = rlen; + sr->in_body = body; + + if (!body) { + push(sr); + + for (i = 0; i < 4; ++i) { + if (mask & 0x8) + set_reg(sr->curr.reg + unw.save_order[i], UNW_WHERE_GR, + sr->region_start + sr->region_len - 1, grsave++); + mask <<= 1; + } + sr->gr_save_loc = grsave; + sr->any_spills = 0; + sr->imask = NULL; + sr->spill_offset = 0x10; /* default to psp+16 */ + } +} + +/* + * Prologue descriptors. + */ + +static inline void +desc_abi (unsigned char abi, unsigned char context, struct unw_state_record *sr) +{ + if (abi == 3 && context == 'i') { + sr->flags |= UNW_FLAG_INTERRUPT_FRAME; + UNW_DPRINT(3, "unwind.%s: interrupt frame\n", __FUNCTION__); + } + else + UNW_DPRINT(0, "unwind%s: ignoring unwabi(abi=0x%x,context=0x%x)\n", + __FUNCTION__, abi, context); +} + +static inline void +desc_br_gr (unsigned char brmask, unsigned char gr, struct unw_state_record *sr) +{ + int i; + + for (i = 0; i < 5; ++i) { + if (brmask & 1) + set_reg(sr->curr.reg + UNW_REG_B1 + i, UNW_WHERE_GR, + sr->region_start + sr->region_len - 1, gr++); + brmask >>= 1; + } +} + +static inline void +desc_br_mem (unsigned char brmask, struct unw_state_record *sr) +{ + int i; + + for (i = 0; i < 5; ++i) { + if (brmask & 1) { + set_reg(sr->curr.reg + UNW_REG_B1 + i, UNW_WHERE_SPILL_HOME, + sr->region_start + sr->region_len - 1, 0); + sr->any_spills = 1; + } + brmask >>= 1; + } +} + +static inline void +desc_frgr_mem (unsigned char grmask, unw_word frmask, struct unw_state_record *sr) +{ + int i; + + for (i = 0; i < 4; ++i) { + if ((grmask & 1) != 0) { + set_reg(sr->curr.reg + UNW_REG_R4 + i, UNW_WHERE_SPILL_HOME, + sr->region_start + sr->region_len - 1, 0); + sr->any_spills = 1; + } + grmask >>= 1; + } + for (i = 0; i < 20; ++i) { + if ((frmask & 1) != 0) { + int base = (i < 4) ? UNW_REG_F2 : UNW_REG_F16 - 4; + set_reg(sr->curr.reg + base + i, UNW_WHERE_SPILL_HOME, + sr->region_start + sr->region_len - 1, 0); + sr->any_spills = 1; + } + frmask >>= 1; + } +} + +static inline void +desc_fr_mem (unsigned char frmask, struct unw_state_record *sr) +{ + int i; + + for (i = 0; i < 4; ++i) { + if ((frmask & 1) != 0) { + set_reg(sr->curr.reg + UNW_REG_F2 + i, UNW_WHERE_SPILL_HOME, + sr->region_start + sr->region_len - 1, 0); + sr->any_spills = 1; + } + frmask >>= 1; + } +} + +static inline void +desc_gr_gr (unsigned char grmask, unsigned char gr, struct unw_state_record *sr) +{ + int i; + + for (i = 0; i < 4; ++i) { + if ((grmask & 1) != 0) + set_reg(sr->curr.reg + UNW_REG_R4 + i, UNW_WHERE_GR, + sr->region_start + sr->region_len - 1, gr++); + grmask >>= 1; + } +} + +static inline void +desc_gr_mem (unsigned char grmask, struct unw_state_record *sr) +{ + int i; + + for (i = 0; i < 4; ++i) { + if ((grmask & 1) != 0) { + set_reg(sr->curr.reg + UNW_REG_R4 + i, UNW_WHERE_SPILL_HOME, + sr->region_start + sr->region_len - 1, 0); + sr->any_spills = 1; + } + grmask >>= 1; + } +} + +static inline void +desc_mem_stack_f (unw_word t, unw_word size, struct unw_state_record *sr) +{ + set_reg(sr->curr.reg + UNW_REG_PSP, UNW_WHERE_NONE, + sr->region_start + min_t(int, t, sr->region_len - 1), 16*size); +} + +static inline void +desc_mem_stack_v (unw_word t, struct unw_state_record *sr) +{ + sr->curr.reg[UNW_REG_PSP].when = sr->region_start + min_t(int, t, sr->region_len - 1); +} + +static inline void +desc_reg_gr (unsigned char reg, unsigned char dst, struct unw_state_record *sr) +{ + set_reg(sr->curr.reg + reg, UNW_WHERE_GR, sr->region_start + sr->region_len - 1, dst); +} + +static inline void +desc_reg_psprel (unsigned char reg, unw_word pspoff, struct unw_state_record *sr) +{ + set_reg(sr->curr.reg + reg, UNW_WHERE_PSPREL, sr->region_start + sr->region_len - 1, + 0x10 - 4*pspoff); +} + +static inline void +desc_reg_sprel (unsigned char reg, unw_word spoff, struct unw_state_record *sr) +{ + set_reg(sr->curr.reg + reg, UNW_WHERE_SPREL, sr->region_start + sr->region_len - 1, + 4*spoff); +} + +static inline void +desc_rp_br (unsigned char dst, struct unw_state_record *sr) +{ + sr->return_link_reg = dst; +} + +static inline void +desc_reg_when (unsigned char regnum, unw_word t, struct unw_state_record *sr) +{ + struct unw_reg_info *reg = sr->curr.reg + regnum; + + if (reg->where == UNW_WHERE_NONE) + reg->where = UNW_WHERE_GR_SAVE; + reg->when = sr->region_start + min_t(int, t, sr->region_len - 1); +} + +static inline void +desc_spill_base (unw_word pspoff, struct unw_state_record *sr) +{ + sr->spill_offset = 0x10 - 4*pspoff; +} + +static inline unsigned char * +desc_spill_mask (unsigned char *imaskp, struct unw_state_record *sr) +{ + sr->imask = imaskp; + return imaskp + (2*sr->region_len + 7)/8; +} + +/* + * Body descriptors. + */ +static inline void +desc_epilogue (unw_word t, unw_word ecount, struct unw_state_record *sr) +{ + sr->epilogue_start = sr->region_start + sr->region_len - 1 - t; + sr->epilogue_count = ecount + 1; +} + +static inline void +desc_copy_state (unw_word label, struct unw_state_record *sr) +{ + struct unw_labeled_state *ls; + + for (ls = sr->labeled_states; ls; ls = ls->next) { + if (ls->label == label) { + free_state_stack(&sr->curr); + memcpy(&sr->curr, &ls->saved_state, sizeof(sr->curr)); + sr->curr.next = dup_state_stack(ls->saved_state.next); + return; + } + } + printk(KERN_ERR "unwind: failed to find state labeled 0x%lx\n", label); +} + +static inline void +desc_label_state (unw_word label, struct unw_state_record *sr) +{ + struct unw_labeled_state *ls; + + ls = alloc_labeled_state(); + if (!ls) { + printk(KERN_ERR "unwind.desc_label_state(): out of memory\n"); + return; + } + ls->label = label; + memcpy(&ls->saved_state, &sr->curr, sizeof(ls->saved_state)); + ls->saved_state.next = dup_state_stack(sr->curr.next); + + /* insert into list of labeled states: */ + ls->next = sr->labeled_states; + sr->labeled_states = ls; +} + +/* + * General descriptors. + */ + +static inline int +desc_is_active (unsigned char qp, unw_word t, struct unw_state_record *sr) +{ + if (sr->when_target <= sr->region_start + min_t(int, t, sr->region_len - 1)) + return 0; + if (qp > 0) { + if ((sr->pr_val & (1UL << qp)) == 0) + return 0; + sr->pr_mask |= (1UL << qp); + } + return 1; +} + +static inline void +desc_restore_p (unsigned char qp, unw_word t, unsigned char abreg, struct unw_state_record *sr) +{ + struct unw_reg_info *r; + + if (!desc_is_active(qp, t, sr)) + return; + + r = sr->curr.reg + decode_abreg(abreg, 0); + r->where = UNW_WHERE_NONE; + r->when = UNW_WHEN_NEVER; + r->val = 0; +} + +static inline void +desc_spill_reg_p (unsigned char qp, unw_word t, unsigned char abreg, unsigned char x, + unsigned char ytreg, struct unw_state_record *sr) +{ + enum unw_where where = UNW_WHERE_GR; + struct unw_reg_info *r; + + if (!desc_is_active(qp, t, sr)) + return; + + if (x) + where = UNW_WHERE_BR; + else if (ytreg & 0x80) + where = UNW_WHERE_FR; + + r = sr->curr.reg + decode_abreg(abreg, 0); + r->where = where; + r->when = sr->region_start + min_t(int, t, sr->region_len - 1); + r->val = (ytreg & 0x7f); +} + +static inline void +desc_spill_psprel_p (unsigned char qp, unw_word t, unsigned char abreg, unw_word pspoff, + struct unw_state_record *sr) +{ + struct unw_reg_info *r; + + if (!desc_is_active(qp, t, sr)) + return; + + r = sr->curr.reg + decode_abreg(abreg, 1); + r->where = UNW_WHERE_PSPREL; + r->when = sr->region_start + min_t(int, t, sr->region_len - 1); + r->val = 0x10 - 4*pspoff; +} + +static inline void +desc_spill_sprel_p (unsigned char qp, unw_word t, unsigned char abreg, unw_word spoff, + struct unw_state_record *sr) +{ + struct unw_reg_info *r; + + if (!desc_is_active(qp, t, sr)) + return; + + r = sr->curr.reg + decode_abreg(abreg, 1); + r->where = UNW_WHERE_SPREL; + r->when = sr->region_start + min_t(int, t, sr->region_len - 1); + r->val = 4*spoff; +} + +#define UNW_DEC_BAD_CODE(code) printk(KERN_ERR "unwind: unknown code 0x%02x\n", \ + code); + +/* + * region headers: + */ +#define UNW_DEC_PROLOGUE_GR(fmt,r,m,gr,arg) desc_prologue(0,r,m,gr,arg) +#define UNW_DEC_PROLOGUE(fmt,b,r,arg) desc_prologue(b,r,0,32,arg) +/* + * prologue descriptors: + */ +#define UNW_DEC_ABI(fmt,a,c,arg) desc_abi(a,c,arg) +#define UNW_DEC_BR_GR(fmt,b,g,arg) desc_br_gr(b,g,arg) +#define UNW_DEC_BR_MEM(fmt,b,arg) desc_br_mem(b,arg) +#define UNW_DEC_FRGR_MEM(fmt,g,f,arg) desc_frgr_mem(g,f,arg) +#define UNW_DEC_FR_MEM(fmt,f,arg) desc_fr_mem(f,arg) +#define UNW_DEC_GR_GR(fmt,m,g,arg) desc_gr_gr(m,g,arg) +#define UNW_DEC_GR_MEM(fmt,m,arg) desc_gr_mem(m,arg) +#define UNW_DEC_MEM_STACK_F(fmt,t,s,arg) desc_mem_stack_f(t,s,arg) +#define UNW_DEC_MEM_STACK_V(fmt,t,arg) desc_mem_stack_v(t,arg) +#define UNW_DEC_REG_GR(fmt,r,d,arg) desc_reg_gr(r,d,arg) +#define UNW_DEC_REG_PSPREL(fmt,r,o,arg) desc_reg_psprel(r,o,arg) +#define UNW_DEC_REG_SPREL(fmt,r,o,arg) desc_reg_sprel(r,o,arg) +#define UNW_DEC_REG_WHEN(fmt,r,t,arg) desc_reg_when(r,t,arg) +#define UNW_DEC_PRIUNAT_WHEN_GR(fmt,t,arg) desc_reg_when(UNW_REG_PRI_UNAT_GR,t,arg) +#define UNW_DEC_PRIUNAT_WHEN_MEM(fmt,t,arg) desc_reg_when(UNW_REG_PRI_UNAT_MEM,t,arg) +#define UNW_DEC_PRIUNAT_GR(fmt,r,arg) desc_reg_gr(UNW_REG_PRI_UNAT_GR,r,arg) +#define UNW_DEC_PRIUNAT_PSPREL(fmt,o,arg) desc_reg_psprel(UNW_REG_PRI_UNAT_MEM,o,arg) +#define UNW_DEC_PRIUNAT_SPREL(fmt,o,arg) desc_reg_sprel(UNW_REG_PRI_UNAT_MEM,o,arg) +#define UNW_DEC_RP_BR(fmt,d,arg) desc_rp_br(d,arg) +#define UNW_DEC_SPILL_BASE(fmt,o,arg) desc_spill_base(o,arg) +#define UNW_DEC_SPILL_MASK(fmt,m,arg) (m = desc_spill_mask(m,arg)) +/* + * body descriptors: + */ +#define UNW_DEC_EPILOGUE(fmt,t,c,arg) desc_epilogue(t,c,arg) |