| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Linus Torvalds (pre-git) | 9869 | 78.01% | 5 | 8.06% |
| David Mosberger-Tang | 1712 | 13.53% | 27 | 43.55% |
| Linus Torvalds | 475 | 3.75% | 4 | 6.45% |
| Keith Owens | 379 | 3.00% | 9 | 14.52% |
| Phil Carmody | 59 | 0.47% | 2 | 3.23% |
| Harvey Harrison | 51 | 0.40% | 1 | 1.61% |
| Robin Holt | 34 | 0.27% | 1 | 1.61% |
| Kirill Korotaev | 17 | 0.13% | 1 | 1.61% |
| Maximilian Attems | 14 | 0.11% | 1 | 1.61% |
| Rusty Russell | 12 | 0.09% | 1 | 1.61% |
| Milind Arun Choudhary | 6 | 0.05% | 1 | 1.61% |
| Greg Banks | 5 | 0.04% | 1 | 1.61% |
| Andrew Morton | 4 | 0.03% | 1 | 1.61% |
| Andreas Schwab | 4 | 0.03% | 1 | 1.61% |
| Thomas Gleixner | 4 | 0.03% | 1 | 1.61% |
| Peter Chubb | 2 | 0.02% | 1 | 1.61% |
| Greg Kroah-Hartman | 1 | 0.01% | 1 | 1.61% |
| Mike Rapoport | 1 | 0.01% | 1 | 1.61% |
| Simon Arlott | 1 | 0.01% | 1 | 1.61% |
| Roel Kluin | 1 | 0.01% | 1 | 1.61% |
| Total | 12651 | 62 |
// SPDX-License-Identifier: GPL-2.0 /* * 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 dependent 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/memblock.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 <linux/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__) # undef inline # 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(unw.lock), .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", __func__, 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", __func__); 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", __func__, 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", __func__, 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", __func__, (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->caller_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", __func__); 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", __func__); } 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", __func__, regnum); return -1; } if (write) if (read_only(addr)) { UNW_DPRINT(0, "unwind.%s: ignoring attempt to write read-only location\n", __func__); } 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", __func__, 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", __func__); } 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->caller_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", __func__, regnum); return -1; } if (write) { if (read_only(addr)) { UNW_DPRINT(0, "unwind.%s: ignoring attempt to write read-only location\n", __func__); } 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", __func__); } 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", __func__, 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", __func__); } 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", __func__); } else UNW_DPRINT(0, "unwind%s: ignoring unwabi(abi=0x%x,context=0x%x)\n", __func__, 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) #define UNW_DEC_COPY_STATE(fmt,l,arg) desc_copy_state(l,arg) #define UNW_DEC_LABEL_STATE(fmt,l,arg) desc_label_state(l,arg) /* * general unwind descriptors: */ #define UNW_DEC_SPILL_REG_P(f,p,t,a,x,y,arg) desc_spill_reg_p(p,t,a,x,y,arg) #define UNW_DEC_SPILL_REG(f,t,a,x,y,arg) desc_spill_reg_p(0,t,a,x,y,arg) #define UNW_DEC_SPILL_PSPREL_P(f,p,t,a,o,arg) desc_spill_psprel_p(p,t,a,o,arg) #define UNW_DEC_SPILL_PSPREL(f,t,a,o,arg) desc_spill_psprel_p(0,t,a,o,arg) #define UNW_DEC_SPILL_SPREL_P(f,p,t,a,o,arg) desc_spill_sprel_p(p,t,a,o,arg) #define UNW_DEC_SPILL_SPREL(f,t,a,o,arg) desc_spill_sprel_p(0,t,a,o,arg) #define UNW_DEC_RESTORE_P(f,p,t,a,arg) desc_restore_p(p,t,a,arg) #define UNW_DEC_RESTORE(f,t,a,arg) desc_restore_p(0,t,a,arg) #include "unwind_decoder.c" /* Unwind scripts. */ static inline unw_hash_index_t hash (unsigned long ip) { /* magic number = ((sqrt(5)-1)/2)*2^64 */ static const unsigned long hashmagic = 0x9e3779b97f4a7c16UL; return (ip >> 4) * hashmagic >> (64 - UNW_LOG_HASH_SIZE); } static inline long cache_match (struct unw_script *script, unsigned long ip, unsigned long pr) { read_lock(&script->lock); if (ip == script->ip && ((pr ^ script->pr_val) & script->pr_mask) == 0) /* keep the read lock... */ return 1; read_unlock(&script->lock); return 0; } static inline struct unw_script * script_lookup (struct unw_frame_info *info) { struct unw_script *script = unw.cache + info->hint; unsigned short index; unsigned long ip, pr; if (UNW_DEBUG_ON(0)) return NULL; /* Always regenerate scripts in debug mode */ STAT(++unw.stat.cache.lookups); ip = info->ip; pr = info->pr; if (cache_match(script, ip, pr)) { STAT(++unw.stat.cache.hinted_hits); return script; } index = unw.hash[hash(ip)]; if (index >= UNW_CACHE_SIZE) return NULL; script = unw.cache + index; while (1) { if (cache_match(script, ip, pr)) { /* update hint; no locking required as single-word writes are atomic */ STAT(++unw.stat.cache.normal_hits); unw.cache[info->prev_script].hint = script - unw.cache; return script; } if (script->coll_chain >= UNW_HASH_SIZE) return NULL; script = unw.cache + script->coll_chain; STAT(++unw.stat.cache.collision_chain_traversals); } } /* * On returning, a write lock for the SCRIPT is still being held. */ static inline struct unw_script * script_new (unsigned long ip) { struct unw_script *script, *prev, *tmp; unw_hash_index_t index; unsigned short head; STAT(++unw.stat.script.news); /* * Can't (easily) use cmpxchg() here because of ABA problem * that is intrinsic in cmpxchg()... */ head = unw.lru_head; script = unw.cache + head; unw.lru_head = script->lru_chain; /* * We'd deadlock here if we interrupted a thread that is holding a read lock on * script->lock. Thus, if the write_trylock() fails, we simply bail out. The * alternative would be to disable interrupts whenever we hold a read-lock, but * that seems silly. */ if (!write_trylock(&script->lock)) return NULL; /* re-insert script at the tail of the LRU chain: */ unw.cache[unw.lru_tail].lru_chain = head; unw.lru_tail = head; /* remove the old script from the hash table (if it's there): */ if (script->ip) { index = hash(script->ip); tmp = unw.cache + unw.hash[index]; prev = NULL; while (1) { if (tmp == script) { if (prev) prev->coll_chain = tmp->coll_chain; else unw.hash[index] = tmp->coll_chain; break; } else prev = tmp; if (tmp->coll_chain >= UNW_CACHE_SIZE) /* old script wasn't in the hash-table */ break; tmp = unw.cache + tmp->coll_chain; } } /* enter new script in the hash table */ index = hash(ip); script->coll_chain = unw.hash[index]; unw.hash[index] = script - unw.cache; script->ip = ip; /* set new IP while we're holding the locks */ STAT(if (script->coll_chain < UNW_CACHE_SIZE) ++unw.stat.script.collisions); script->flags = 0; script->hint = 0; script->count = 0; return script; } static void script_finalize (struct unw_script *script, struct unw_state_record *sr) { script->pr_mask = sr->pr_mask; script->pr_val = sr->pr_val; /* * We could down-grade our write-lock on script->lock here but * the rwlock API doesn't offer atomic lock downgrading, so * we'll just keep the write-lock and release it later when * we're done using the script. */ } static inline void script_emit (struct unw_script *script, struct unw_insn insn) { if (script->count >= UNW_MAX_SCRIPT_LEN) { UNW_DPRINT(0, "unwind.%s: script exceeds maximum size of %u instructions!\n", __func__, UNW_MAX_SCRIPT_LEN); return; } script->insn[script->count++] = insn; } static inline void emit_nat_info (struct unw_state_record *sr, int i, struct unw_script *script) { struct unw_reg_info *r = sr->curr.reg + i; enum unw_insn_opcode opc; struct unw_insn insn; unsigned long val = 0; switch (r->where) { case UNW_WHERE_GR: if (r->val >= 32) { /* register got spilled to a stacked register */ opc = UNW_INSN_SETNAT_TYPE; val = UNW_NAT_REGSTK; } else /* register got spilled to a scratch register */ opc = UNW_INSN_SETNAT_MEMSTK; break; case UNW_WHERE_FR: opc = UNW_INSN_SETNAT_TYPE; val = UNW_NAT_VAL; break; case UNW_WHERE_BR: opc = UNW_INSN_SETNAT_TYPE; val = UNW_NAT_NONE; break; case UNW_WHERE_PSPREL: case UNW_WHERE_SPREL: opc = UNW_INSN_SETNAT_MEMSTK; break; default: UNW_DPRINT(0, "unwind.%s: don't know how to emit nat info for where = %u\n", __func__, r->where); return; } insn.opc = opc; insn.dst = unw.preg_index[i]; insn.val = val; script_emit(script, insn); } static void compile_reg (struct unw_state_record *sr, int i, struct unw_script *script) { struct unw_reg_info *r = sr->curr.reg + i; enum unw_insn_opcode opc; unsigned long val, rval; struct unw_insn insn; long need_nat_info; if (r->where == UNW_WHERE_NONE || r->when >= sr->when_target) return; opc = UNW_INSN_MOVE; val = rval = r->val; need_nat_info = (i >= UNW_REG_R4 && i <= UNW_REG_R7); switch (r->where) { case UNW_WHERE_GR: if (rval >= 32) { opc = UNW_INSN_MOVE_STACKED; val = rval - 32; } else if (rval >= 4 && rval <= 7) { if (need_nat_info) { opc = UNW_INSN_MOVE2; need_nat_info = 0; } val = unw.preg_index[UNW_REG_R4 + (rval - 4)]; } else if (rval == 0) { opc = UNW_INSN_MOVE_CONST; val = 0; } else { /* register got spilled to a scratch register */ opc = UNW_INSN_MOVE_SCRATCH; val = pt_regs_off(rval); } break; case UNW_WHERE_FR: if (rval <= 5) val = unw.preg_index[UNW_REG_F2 + (rval - 2)]; else if (rval >= 16 && rval <= 31) val = unw.preg_index[UNW_REG_F16 + (rval - 16)]; else { opc = UNW_INSN_MOVE_SCRATCH; if (rval <= 11) val = offsetof(struct pt_regs, f6) + 16*(rval - 6); else UNW_DPRINT(0, "unwind.%s: kernel may not touch f%lu\n", __func__, rval); } break; case UNW_WHERE_BR: if (rval >= 1 && rval <= 5) val = unw.preg_index[UNW_REG_B1 + (rval - 1)]; else { opc = UNW_INSN_MOVE_SCRATCH; if (rval == 0) val = offsetof(struct pt_regs, b0); else if (rval == 6) val = offsetof(struct pt_regs, b6); else val = offsetof(struct pt_regs, b7); } break; case UNW_WHERE_SPREL: opc = UNW_INSN_ADD_SP; break; case UNW_WHERE_PSPREL: opc = UNW_INSN_ADD_PSP; break; default: UNW_DPRINT(0, "unwind%s: register %u has unexpected `where' value of %u\n", __func__, i, r->where); break; } insn.opc = opc; insn.dst = unw.preg_index[i]; insn.val = val; script_emit(script, insn); if (need_nat_info) emit_nat_info(sr, i, script); if (i == UNW_REG_PSP) { /* * info->psp must contain the _value_ of the previous * sp, not it's save location. We get this by * dereferencing the value we just stored in * info->psp: */ insn.opc = UNW_INSN_LOAD; insn.dst = insn.val = unw.preg_index[UNW_REG_PSP]; script_emit(script, insn); } } static inline const struct unw_table_entry * lookup (struct unw_table *table, unsigned long rel_ip) { const struct unw_table_entry *e = NULL; unsigned long lo, hi, mid; /* do a binary search for right entry: */ for (lo = 0, hi = table->length; lo < hi; ) { mid = (lo + hi) / 2; e = &table->array[mid]; if (rel_ip < e->start_offset) hi = mid; else if (rel_ip >= e->end_offset) lo = mid + 1; else break; } if (rel_ip < e->start_offset || rel_ip >= e->end_offset) return NULL; return e; } /* * Build an unwind script that unwinds from state OLD_STATE to the * entrypoint of the function that called OLD_STATE. */ static inline struct unw_script * build_script (struct unw_frame_info *info) { const struct unw_table_entry *e = NULL; struct unw_script *script = NULL; struct unw_labeled_state *ls, *next; unsigned long ip = info->ip; struct unw_state_record sr; struct unw_table *table, *prev; struct unw_reg_info *r; struct unw_insn insn; u8 *dp, *desc_end; u64 hdr; int i; STAT(unsigned long start, parse_start;) STAT(++unw.stat.script.builds; start = ia64_get_itc()); /* build state record */ memset(&sr, 0, sizeof(sr)); for (r = sr.curr.reg; r < sr.curr.reg + UNW_NUM_REGS; ++r) r->when = UNW_WHEN_NEVER; sr.pr_val = info->pr; UNW_DPRINT(3, "unwind.%s: ip 0x%lx\n", __func__, ip); script = script_new(ip); if (!script) { UNW_DPRINT(0, "unwind.%s: failed to create unwind script\n", __func__); STAT(unw.stat.script.build_time += ia64_get_itc() - start); return NULL; } unw.cache[info->prev_script].hint = script - unw.cache; /* search the kernels and the modules' unwind tables for IP: */ STAT(parse_start = ia64_get_itc()); prev = NULL; for (table = unw.tables; table; table = table->next) { if (ip >= table->start && ip < table->end) { /* * Leave the kernel unwind table at the very front, * lest moving it breaks some assumption elsewhere. * Otherwise, move the matching table to the second * position in the list so that traversals can benefit * from commonality in backtrace paths. */ if (prev && prev != unw.tables) { /* unw is safe - we're already spinlocked */ prev->next = table->next; table->next = unw.tables->next; unw.tables->next = table; } e = lookup(table, ip - table->segment_base); break; } prev = table; } if (!e) { /* no info, return default unwinder (leaf proc, no mem stack, no saved regs) */ UNW_DPRINT(1, "unwind.%s: no unwind info for ip=0x%lx (prev ip=0x%lx)\n", __func__, ip, unw.cache[info->prev_script].ip); sr.curr.reg[UNW_REG_RP].where = UNW_WHERE_BR; sr.curr.reg[UNW_REG_RP].when = -1; sr.curr.reg[UNW_REG_RP].val = 0; compile_reg(&sr, UNW_REG_RP, script); script_finalize(script, &sr); STAT(unw.stat.script.parse_time += ia64_get_itc() - parse_start); STAT(unw.stat.script.build_time += ia64_get_itc() - start); return script; } sr.when_target = (3*((ip & ~0xfUL) - (table->segment_base + e->start_offset))/16 + (ip & 0xfUL)); hdr = *(u64 *) (table->segment_base + e->info_offset); dp = (u8 *) (table->segment_base + e->info_offset + 8); desc_end = dp + 8*UNW_LENGTH(hdr); while (!sr.done && dp < desc_end) dp = unw_decode(dp, sr.in_body, &sr); if (sr.when_target > sr.epilogue_start) { /* * sp has been restored and all values on the memory stack below * psp also have been restored. */ sr.curr.reg[UNW_REG_PSP].val = 0; sr.curr.reg[UNW_REG_PSP].where = UNW_WHERE_NONE; sr.curr.reg[UNW_REG_PSP].when = UNW_WHEN_NEVER; for (r = sr.curr.reg; r < sr.curr.reg + UNW_NUM_REGS; ++r) if ((r->where == UNW_WHERE_PSPREL && r->val <= 0x10) || r->where == UNW_WHERE_SPREL) { r->val = 0; r->where = UNW_WHERE_NONE; r->when = UNW_WHEN_NEVER; } } script->flags = sr.flags; /* * If RP did't get saved, generate entry for the return link * register. */ if (sr.curr.reg[UNW_REG_RP].when >= sr.when_target) { sr.curr.reg[UNW_REG_RP].where = UNW_WHERE_BR; sr.curr.reg[UNW_REG_RP].when = -1; sr.curr.reg[UNW_REG_RP].val = sr.return_link_reg; UNW_DPRINT(1, "unwind.%s: using default for rp at ip=0x%lx where=%d val=0x%lx\n", __func__, ip, sr.curr.reg[UNW_REG_RP].where, sr.curr.reg[UNW_REG_RP].val); } #ifdef UNW_DEBUG UNW_DPRINT(1, "unwind.%s: state record for func 0x%lx, t=%u:\n", __func__, table->segment_base + e->start_offset, sr.when_target); for (r = sr.curr.reg; r < sr.curr.reg + UNW_NUM_REGS; ++r) { if (r->where != UNW_WHERE_NONE || r->when != UNW_WHEN_NEVER) { UNW_DPRINT(1, " %s <- ", unw.preg_name[r - sr.curr.reg]); switch (r->where) { case UNW_WHERE_GR: UNW_DPRINT(1, "r%lu", r->val); break; case UNW_WHERE_FR: UNW_DPRINT(1, "f%lu", r->val); break; case UNW_WHERE_BR: UNW_DPRINT(1, "b%lu", r->val); break; case UNW_WHERE_SPREL: UNW_DPRINT(1, "[sp+0x%lx]", r->val); break; case UNW_WHERE_PSPREL: UNW_DPRINT(1, "[psp+0x%lx]", r->val); break; case UNW_WHERE_NONE: UNW_DPRINT(1, "%s+0x%lx", unw.preg_name[r - sr.curr.reg], r->val); break; default: UNW_DPRINT(1, "BADWHERE(%d)", r->where); break; } UNW_DPRINT(1, "\t\t%d\n", r->when); } } #endif STAT(unw.stat.script.parse_time += ia64_get_itc() - parse_start); /* translate state record into unwinder instructions: */ /* * First, set psp if we're dealing with a fixed-size frame; * subsequent instructions may depend on this value. */ if (sr.when_target > sr.curr.reg[UNW_REG_PSP].when && (sr.curr.reg[UNW_REG_PSP].where == UNW_WHERE_NONE) && sr.curr.reg[UNW_REG_PSP].val != 0) { /* new psp is sp plus frame size */ insn.opc = UNW_INSN_ADD; insn.dst = offsetof(struct unw_frame_info, psp)/8; insn.val = sr.curr.reg[UNW_REG_PSP].val; /* frame size */ script_emit(script, insn); } /* determine where the primary UNaT is: */ if (sr.when_target < sr.curr.reg[UNW_REG_PRI_UNAT_GR].when) i = UNW_REG_PRI_UNAT_MEM; else if (sr.when_target < sr.curr.reg[UNW_REG_PRI_UNAT_MEM].when) i = UNW_REG_PRI_UNAT_GR; else if (sr.curr.reg[UNW_REG_PRI_UNAT_MEM].when > sr.curr.reg[UNW_REG_PRI_UNAT_GR].when) i = UNW_REG_PRI_UNAT_MEM; else i = UNW_REG_PRI_UNAT_GR; compile_reg(&sr, i, script); for (i = UNW_REG_BSP; i < UNW_NUM_REGS; ++i) compile_reg(&sr, i, script); /* free labeled register states & stack: */ STAT(parse_start = ia64_get_itc()); for (ls = sr.labeled_states; ls; ls = next) { next = ls->next; free_state_stack(&ls->saved_state); free_labeled_state(ls); } free_state_stack(&sr.curr); STAT(unw.stat.script.parse_time += ia64_get_itc() - parse_start); script_finalize(script, &sr); STAT(unw.stat.script.build_time += ia64_get_itc() - start); return script; } /* * Apply the unwinding actions represented by OPS and update SR to * reflect the state that existed upon entry to the function that this * unwinder represents. */ static inline void run_script (struct unw_script *script, struct unw_frame_info *state) { struct unw_insn *ip, *limit, next_insn; unsigned long opc, dst, val, off; unsigned long *s = (unsigned long *) state; STAT(unsigned long start;) STAT(++unw.stat.script.runs; start = ia64_get_itc()); state->flags = script->flags; ip = script->insn; limit = script->insn + script->count; next_insn = *ip; while (ip++ < limit) { opc = next_insn.opc; dst = next_insn.dst; val = next_insn.val; next_insn = *ip; redo: switch (opc) { case UNW_INSN_ADD: s[dst] += val; break; case UNW_INSN_MOVE2: if (!s[val]) goto lazy_init; s[dst+1] = s[val+1]; s[dst] = s[val]; break; case UNW_INSN_MOVE: if (!s[val]) goto lazy_init; s[dst] = s[val]; break; case UNW_INSN_MOVE_SCRATCH: if (state->pt) { s[dst] = (unsigned long) get_scratch_regs(state) + val; } else { s[dst] = 0; UNW_DPRINT(0, "unwind.%s: no state->pt, dst=%ld, val=%ld\n", __func__, dst, val); } break; case UNW_INSN_MOVE_CONST: if (val == 0) s[dst] = (unsigned long) &unw.r0; else { s[dst] = 0; UNW_DPRINT(0, "unwind.%s: UNW_INSN_MOVE_CONST bad val=%ld\n", __func__, val); } break; case UNW_INSN_MOVE_STACKED: s[dst] = (unsigned long) ia64_rse_skip_regs((unsigned long *)state->bsp, val); break; case UNW_INSN_ADD_PSP: s[dst] = state->psp + val; break; case UNW_INSN_ADD_SP: s[dst] = state->sp + val; break; case UNW_INSN_SETNAT_MEMSTK: if (!state->pri_unat_loc) state->pri_unat_loc = &state->sw->caller_unat; /* register off. is a multiple of 8, so the least 3 bits (type) are 0 */ s[dst+1] = ((unsigned long) state->pri_unat_loc - s[dst]) | UNW_NAT_MEMSTK; break; case UNW_INSN_SETNAT_TYPE: s[dst+1] = val; break; case UNW_INSN_LOAD: #ifdef UNW_DEBUG if ((s[val] & (local_cpu_data->unimpl_va_mask | 0x7)) != 0 || s[val] < TASK_SIZE) { UNW_DPRINT(0, "unwind.%s: rejecting bad psp=0x%lx\n", __func__, s[val]); break; } #endif s[dst] = *(unsigned long *) s[val]; break; } } STAT(unw.stat.script.run_time += ia64_get_itc() - start); return; lazy_init: off = unw.sw_off[val]; s[val] = (unsigned long) state->sw + off; if (off >= offsetof(struct switch_stack, r4) && off <= offsetof(struct switch_stack, r7)) /* * We're initializing a general register: init NaT info, too. Note that * the offset is a multiple of 8 which gives us the 3 bits needed for * the type field. */ s[val+1] = (offsetof(struct switch_stack, ar_unat) - off) | UNW_NAT_MEMSTK; goto redo; } static int find_save_locs (struct unw_frame_info *info) { int have_write_lock = 0; struct unw_script *scr; unsigned long flags = 0; if ((info->ip & (local_cpu_data->unimpl_va_mask | 0xf)) || info->ip < TASK_SIZE) { /* don't let obviously bad addresses pollute the cache */ /* FIXME: should really be level 0 but it occurs too often. KAO */ UNW_DPRINT(1, "unwind.%s: rejecting bad ip=0x%lx\n", __func__, info->ip); info->rp_loc = NULL; return -1; } scr = script_lookup(info); if (!scr) { spin_lock_irqsave(&unw.lock, flags); scr = build_script(info); if (!scr) { spin_unlock_irqrestore(&unw.lock, flags); UNW_DPRINT(0, "unwind.%s: failed to locate/build unwind script for ip %lx\n", __func__, info->ip); return -1; } have_write_lock = 1; } info->hint = scr->hint; info->prev_script = scr - unw.cache; run_script(scr, info); if (have_write_lock) { write_unlock(&scr->lock); spin_unlock_irqrestore(&unw.lock, flags); } else read_unlock(&scr->lock); return 0; } static int unw_valid(const struct unw_frame_info *info, unsigned long* p) { unsigned long loc = (unsigned long)p; return (loc >= info->regstk.limit && loc < info->regstk.top) || (loc >= info->memstk.top && loc < info->memstk.limit); } int unw_unwind (struct unw_frame_info *info) { unsigned long prev_ip, prev_sp, prev_bsp; unsigned long ip, pr, num_regs; STAT(unsigned long start, flags;) int retval; STAT(local_irq_save(flags); ++unw.stat.api.unwinds; start = ia64_get_itc()); prev_ip = info->ip; prev_sp = info->sp; prev_bsp = info->bsp; /* validate the return IP pointer */ if (!unw_valid(info, info->rp_loc)) { /* FIXME: should really be level 0 but it occurs too often. KAO */ UNW_DPRINT(1, "unwind.%s: failed to locate return link (ip=0x%lx)!\n", __func__, info->ip); STAT(unw.stat.api.unwind_time += ia64_get_itc() - start; local_irq_restore(flags)); return -1; } /* restore the ip */ ip = info->ip = *info->rp_loc; if (ip < GATE_ADDR) { UNW_DPRINT(2, "unwind.%s: reached user-space (ip=0x%lx)\n", __func__, ip); STAT(unw.stat.api.unwind_time += ia64_get_itc() - start; local_irq_restore(flags)); return -1; } /* validate the previous stack frame pointer */ if (!unw_valid(info, info->pfs_loc)) { UNW_DPRINT(0, "unwind.%s: failed to locate ar.pfs!\n", __func__); STAT(unw.stat.api.unwind_time += ia64_get_itc() - start; local_irq_restore(flags)); return -1; } /* restore the cfm: */ info->cfm_loc = info->pfs_loc; /* restore the bsp: */ pr = info->pr; num_regs = 0; if ((info->flags & UNW_FLAG_INTERRUPT_FRAME)) { info->pt = info->sp + 16; if ((pr & (1UL << PRED_NON_SYSCALL)) != 0) num_regs = *info->cfm_loc & 0x7f; /* size of frame */ info->pfs_loc = (unsigned long *) (info->pt + offsetof(struct pt_regs, ar_pfs)); UNW_DPRINT(3, "unwind.%s: interrupt_frame pt 0x%lx\n", __func__, info->pt); } else num_regs = (*info->cfm_loc >> 7) & 0x7f; /* size of locals */ info->bsp = (unsigned long) ia64_rse_skip_regs((unsigned long *) info->bsp, -num_regs); if (info->bsp < info->regstk.limit || info->bsp > info->regstk.top) { UNW_DPRINT(0, "unwind.%s: bsp (0x%lx) out of range [0x%lx-0x%lx]\n", __func__, info->bsp, info->regstk.limit, info->regstk.top); STAT(unw.stat.api.unwind_time += ia64_get_itc() - start; local_irq_restore(flags)); return -1; } /* restore the sp: */ info->sp = info->psp; if (info->sp < info->memstk.top || info->sp > info->memstk.limit) { UNW_DPRINT(0, "unwind.%s: sp (0x%lx) out of range [0x%lx-0x%lx]\n", __func__, info->sp, info->memstk.top, info->memstk.limit); STAT(unw.stat.api.unwind_time += ia64_get_itc() - start; local_irq_restore(flags)); return -1; } if (info->ip == prev_ip && info->sp == prev_sp && info->bsp == prev_bsp) { UNW_DPRINT(0, "unwind.%s: ip, sp, bsp unchanged; stopping here (ip=0x%lx)\n", __func__, ip); STAT(unw.stat.api.unwind_time += ia64_get_itc() - start; local_irq_restore(flags)); return -1; } /* as we unwind, the saved ar.unat becomes the primary unat: */ info->pri_unat_loc = info->unat_loc; /* finally, restore the predicates: */ unw_get_pr(info, &info->pr); retval = find_save_locs(info); STAT(unw.stat.api.unwind_time += ia64_get_itc() - start; local_irq_restore(flags)); return retval; } EXPORT_SYMBOL(unw_unwind); int unw_unwind_to_user (struct unw_frame_info *info) { unsigned long ip, sp, pr = info->pr; do { unw_get_sp(info, &sp); if ((long)((unsigned long)info->task + IA64_STK_OFFSET - sp) < IA64_PT_REGS_SIZE) { UNW_DPRINT(0, "unwind.%s: ran off the top of the kernel stack\n", __func__); break; } if (unw_is_intr_frame(info) && (pr & (1UL << PRED_USER_STACK))) return 0; if (unw_get_pr (info, &pr) < 0) { unw_get_rp(info, &ip); UNW_DPRINT(0, "unwind.%s: failed to read " "predicate register (ip=0x%lx)\n", __func__, ip); return -1; } } while (unw_unwind(info) >= 0); unw_get_ip(info, &ip); UNW_DPRINT(0, "unwind.%s: failed to unwind to user-level (ip=0x%lx)\n", __func__, ip); return -1; } EXPORT_SYMBOL(unw_unwind_to_user); static void init_frame_info (struct unw_frame_info *info, struct task_struct *t, struct switch_stack *sw, unsigned long stktop) { unsigned long rbslimit, rbstop, stklimit; STAT(unsigned long start, flags;) STAT(local_irq_save(flags); ++unw.stat.api.inits; start = ia64_get_itc()); /* * Subtle stuff here: we _could_ unwind through the switch_stack frame but we * don't want to do that because it would be slow as each preserved register would * have to be processed. Instead, what we do here is zero out the frame info and * start the unwind process at the function that created the switch_stack frame. * When a preserved value in switch_stack needs to be accessed, run_script() will * initialize the appropriate pointer on demand. */ memset(info, 0, sizeof(*info)); rbslimit = (unsigned long) t + IA64_RBS_OFFSET; stklimit = (unsigned long) t + IA64_STK_OFFSET; rbstop = sw->ar_bspstore; if (rbstop > stklimit || rbstop < rbslimit) rbstop = rbslimit; if (stktop <= rbstop) stktop = rbstop; if (stktop > stklimit) stktop = stklimit; info->regstk.limit = rbslimit; info->regstk.top = rbstop; info->memstk.limit = stklimit; info->memstk.top = stktop; info->task = t; info->sw = sw; info->sp = info->psp = stktop; info->pr = sw->pr; UNW_DPRINT(3, "unwind.%s:\n" " task 0x%lx\n" " rbs = [0x%lx-0x%lx)\n" " stk = [0x%lx-0x%lx)\n" " pr 0x%lx\n" " sw 0x%lx\n" " sp 0x%lx\n", __func__, (unsigned long) t, rbslimit, rbstop, stktop, stklimit, info->pr, (unsigned long) info->sw, info->sp); STAT(unw.stat.api.init_time += ia64_get_itc() - start; local_irq_restore(flags)); } void unw_init_frame_info (struct unw_frame_info *info, struct task_struct *t, struct switch_stack *sw) { unsigned long sol; init_frame_info(info, t, sw, (unsigned long) (sw + 1) - 16); info->cfm_loc = &sw->ar_pfs; sol = (*info->cfm_loc >> 7) & 0x7f; info->bsp = (unsigned long) ia64_rse_skip_regs((unsigned long *) info->regstk.top, -sol); info->ip = sw->b0; UNW_DPRINT(3, "unwind.%s:\n" " bsp 0x%lx\n" " sol 0x%lx\n" " ip 0x%lx\n", __func__, info->bsp, sol, info->ip); find_save_locs(info); } EXPORT_SYMBOL(unw_init_frame_info); void unw_init_from_blocked_task (struct unw_frame_info *info, struct task_struct *t) { struct switch_stack *sw = (struct switch_stack *) (t->thread.ksp + 16); UNW_DPRINT(1, "unwind.%s\n", __func__); unw_init_frame_info(info, t, sw); } EXPORT_SYMBOL(unw_init_from_blocked_task); static void init_unwind_table (struct unw_table *table, const char *name, unsigned long segment_base, unsigned long gp, const void *table_start, const void *table_end) { const struct unw_table_entry *start = table_start, *end = table_end; table->name = name; table->segment_base = segment_base; table->gp = gp; table->start = segment_base + start[0].start_offset; table->end = segment_base + end[-1].end_offset; table->array = start; table->length = end - start; } void * unw_add_unwind_table (const char *name, unsigned long segment_base, unsigned long gp, const void *table_start, const void *table_end) { const struct unw_table_entry *start = table_start, *end = table_end; struct unw_table *table; unsigned long flags; if (end - start <= 0) { UNW_DPRINT(0, "unwind.%s: ignoring attempt to insert empty unwind table\n", __func__); return NULL; } table = kmalloc(sizeof(*table), GFP_USER); if (!table) return NULL; init_unwind_table(table, name, segment_base, gp, table_start, table_end); spin_lock_irqsave(&unw.lock, flags); { /* keep kernel unwind table at the front (it's searched most commonly): */ table->next = unw.tables->next; unw.tables->next = table; } spin_unlock_irqrestore(&unw.lock, flags); return table; } void unw_remove_unwind_table (void *handle) { struct unw_table *table, *prev; struct unw_script *tmp; unsigned long flags; long index; if (!handle) { UNW_DPRINT(0, "unwind.%s: ignoring attempt to remove non-existent unwind table\n", __func__); return; } table = handle; if (table == &unw.kernel_table) { UNW_DPRINT(0, "unwind.%s: sorry, freeing the kernel's unwind table is a " "no-can-do!\n", __func__); return; } spin_lock_irqsave(&unw.lock, flags); { /* first, delete the table: */ for (prev = (struct unw_table *) &unw.tables; prev; prev = prev->next) if (prev->next == table) break; if (!prev) { UNW_DPRINT(0, "unwind.%s: failed to find unwind table %p\n", __func__, (void *) table); spin_unlock_irqrestore(&unw.lock, flags); return; } prev->next = table->next; } spin_unlock_irqrestore(&unw.lock, flags); /* next, remove hash table entries for this table */ for (index = 0; index < UNW_HASH_SIZE; ++index) { tmp = unw.cache + unw.hash[index]; if (unw.hash[index] >= UNW_CACHE_SIZE || tmp->ip < table->start || tmp->ip >= table->end) continue; write_lock(&tmp->lock); { if (tmp->ip >= table->start && tmp->ip < table->end) { unw.hash[index] = tmp->coll_chain; tmp->ip = 0; } } write_unlock(&tmp->lock); } kfree(table); } static int __init create_gate_table (void) { const struct unw_table_entry *entry, *start, *end; unsigned long *lp, segbase = GATE_ADDR; size_t info_size, size; char *info; Elf64_Phdr *punw = NULL, *phdr = (Elf64_Phdr *) (GATE_ADDR + GATE_EHDR->e_phoff); int i; for (i = 0; i < GATE_EHDR->e_phnum; ++i, ++phdr) if (phdr->p_type == PT_IA_64_UNWIND) { punw = phdr; break; } if (!punw) { printk("%s: failed to find gate DSO's unwind table!\n", __func__); return 0; } start = (const struct unw_table_entry *) punw->p_vaddr; end = (struct unw_table_entry *) ((char *) start + punw->p_memsz); size = 0; unw_add_unwind_table("linux-gate.so", segbase, 0, start, end); for (entry = start; entry < end; ++entry) size += 3*8 + 8 + 8*UNW_LENGTH(*(u64 *) (segbase + entry->info_offset)); size += 8; /* reserve space for "end of table" marker */ unw.gate_table = kmalloc(size, GFP_KERNEL); if (!unw.gate_table) { unw.gate_table_size = 0; printk(KERN_ERR "%s: unable to create unwind data for gate page!\n", __func__); return 0; } unw.gate_table_size = size; lp = unw.gate_table; info = (char *) unw.gate_table + size; for (entry = start; entry < end; ++entry, lp += 3) { info_size = 8 + 8*UNW_LENGTH(*(u64 *) (segbase + entry->info_offset)); info -= info_size; memcpy(info, (char *) segbase + entry->info_offset, info_size); lp[0] = segbase + entry->start_offset; /* start */ lp[1] = segbase + entry->end_offset; /* end */ lp[2] = info - (char *) unw.gate_table; /* info */ } *lp = 0; /* end-of-table marker */ return 0; } __initcall(create_gate_table); void __init unw_init (void) { extern char __gp[]; extern void unw_hash_index_t_is_too_narrow (void); long i, off; if (8*sizeof(unw_hash_index_t) < UNW_LOG_HASH_SIZE) unw_hash_index_t_is_too_narrow(); unw.sw_off[unw.preg_index[UNW_REG_PRI_UNAT_GR]] = SW(CALLER_UNAT); unw.sw_off[unw.preg_index[UNW_REG_BSPSTORE]] = SW(AR_BSPSTORE); unw.sw_off[unw.preg_index[UNW_REG_PFS]] = SW(AR_PFS); unw.sw_off[unw.preg_index[UNW_REG_RP]] = SW(B0); unw.sw_off[unw.preg_index[UNW_REG_UNAT]] = SW(CALLER_UNAT); unw.sw_off[unw.preg_index[UNW_REG_PR]] = SW(PR); unw.sw_off[unw.preg_index[UNW_REG_LC]] = SW(AR_LC); unw.sw_off[unw.preg_index[UNW_REG_FPSR]] = SW(AR_FPSR); for (i = UNW_REG_R4, off = SW(R4); i <= UNW_REG_R7; ++i, off += 8) unw.sw_off[unw.preg_index[i]] = off; for (i = UNW_REG_B1, off = SW(B1); i <= UNW_REG_B5; ++i, off += 8) unw.sw_off[unw.preg_index[i]] = off; for (i = UNW_REG_F2, off = SW(F2); i <= UNW_REG_F5; ++i, off += 16) unw.sw_off[unw.preg_index[i]] = off; for (i = UNW_REG_F16, off = SW(F16); i <= UNW_REG_F31; ++i, off += 16) unw.sw_off[unw.preg_index[i]] = off; for (i = 0; i < UNW_CACHE_SIZE; ++i) { if (i > 0) unw.cache[i].lru_chain = (i - 1); unw.cache[i].coll_chain = -1; rwlock_init(&unw.cache[i].lock); } unw.lru_head = UNW_CACHE_SIZE - 1; unw.lru_tail = 0; init_unwind_table(&unw.kernel_table, "kernel", KERNEL_START, (unsigned long) __gp, __start_unwind, __end_unwind); } /* * DEPRECATED DEPRECATED DEPRECATED DEPRECATED DEPRECATED DEPRECATED DEPRECATED * * This system call has been deprecated. The new and improved way to get * at the kernel's unwind info is via the gate DSO. The address of the * ELF header for this DSO is passed to user-level via AT_SYSINFO_EHDR. * * DEPRECATED DEPRECATED DEPRECATED DEPRECATED DEPRECATED DEPRECATED DEPRECATED * * This system call copies the unwind data into the buffer pointed to by BUF and returns * the size of the unwind data. If BUF_SIZE is smaller than the size of the unwind data * or if BUF is NULL, nothing is copied, but the system call still returns the size of the * unwind data. * * The first portion of the unwind data contains an unwind table and rest contains the * associated unwind info (in no particular order). The unwind table consists of a table * of entries of the form: * * u64 start; (64-bit address of start of function) * u64 end; (64-bit address of start of function) * u64 info; (BUF-relative offset to unwind info) * * The end of the unwind table is indicated by an entry with a START address of zero. * * Please see the IA-64 Software Conventions and Runtime Architecture manual for details * on the format of the unwind info. * * ERRORS * EFAULT BUF points outside your accessible address space. */ asmlinkage long sys_getunwind (void __user *buf, size_t buf_size) { if (buf && buf_size >= unw.gate_table_size) if (copy_to_user(buf, unw.gate_table, unw.gate_table_size) != 0) return -EFAULT; return unw.gate_table_size; }
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with Cregit http://github.com/cregit/cregit
Version 2.0-RC1