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-rw-r--r--gnu/usr.bin/binutils/gdb/kvm-fbsd.c941
1 files changed, 941 insertions, 0 deletions
diff --git a/gnu/usr.bin/binutils/gdb/kvm-fbsd.c b/gnu/usr.bin/binutils/gdb/kvm-fbsd.c
new file mode 100644
index 0000000..9419b6a
--- /dev/null
+++ b/gnu/usr.bin/binutils/gdb/kvm-fbsd.c
@@ -0,0 +1,941 @@
+/* Live and postmortem kernel debugging functions for FreeBSD.
+ Copyright 1996 Free Software Foundation, Inc.
+
+This file is part of GDB.
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+
+#include "defs.h"
+
+#include <errno.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <sys/sysctl.h>
+#include <sys/param.h>
+#include <sys/time.h>
+#include <sys/proc.h>
+#include <sys/user.h>
+#include "frame.h" /* required by inferior.h */
+#include "inferior.h"
+#include "symtab.h"
+#include "command.h"
+#include "bfd.h"
+#include "target.h"
+#include "gdbcore.h"
+#include <sys/stat.h>
+#include <unistd.h>
+#include <vm/vm.h>
+#include <vm/vm_param.h>
+
+#include <machine/vmparam.h>
+#include <machine/pcb.h>
+#include <machine/frame.h>
+
+static void kcore_files_info PARAMS ((struct target_ops *));
+
+static void kcore_close PARAMS ((int));
+
+static void get_kcore_registers PARAMS ((int));
+
+static int kcore_xfer_kmem PARAMS ((CORE_ADDR, char *, int, int, struct target_ops *));
+
+static int xfer_umem PARAMS ((CORE_ADDR, char *, int, int));
+
+static CORE_ADDR ksym_lookup PARAMS ((const char *));
+
+static int read_pcb PARAMS ((int, CORE_ADDR));
+
+static struct proc * curProc PARAMS ((void));
+
+static int set_proc_context PARAMS ((CORE_ADDR paddr));
+
+static void kcore_open PARAMS ((char *filename, int from_tty));
+
+static void kcore_detach PARAMS ((char *args, int from_tty));
+
+static void set_proc_cmd PARAMS ((char *arg, int from_tty));
+
+static CORE_ADDR kvtophys PARAMS ((int, CORE_ADDR));
+
+static int physrd PARAMS ((int, u_int, char*, int));
+
+static int kvm_open PARAMS ((const char *efile, char *cfile, char *sfile,
+ int perm, char *errout));
+
+static int kvm_close PARAMS ((int fd));
+
+static int kvm_write PARAMS ((int core_kd, CORE_ADDR memaddr,
+ char *myaddr, int len));
+
+static int kvm_read PARAMS ((int core_kd, CORE_ADDR memaddr,
+ char *myaddr, int len));
+
+static int kvm_uread PARAMS ((int core_kd, struct proc *p,
+ CORE_ADDR memaddr, char *myaddr,
+ int len));
+
+static int kernel_core_file_hook PARAMS ((int fd, CORE_ADDR addr,
+ char *buf, int len));
+
+static struct kinfo_proc * kvm_getprocs PARAMS ((int cfd, int op,
+ CORE_ADDR proc, int *cnt));
+
+extern struct target_ops kcore_ops; /* Forward decl */
+
+/* Non-zero means we are debugging a kernel core file */
+int kernel_debugging = 0;
+int kernel_writablecore = 0;
+
+static char *core_file;
+static int core_kd = -1;
+static struct proc *cur_proc;
+static CORE_ADDR kernel_start;
+
+/*
+ * Read the "thing" at kernel address 'addr' into the space pointed to
+ * by point. The length of the "thing" is determined by the type of p.
+ * Result is non-zero if transfer fails.
+ */
+#define kvread(addr, p) \
+ (target_read_memory ((CORE_ADDR)(addr), (char *)(p), sizeof(*(p))))
+
+
+
+/*
+ * The following is FreeBSD-specific hackery to decode special frames
+ * and elide the assembly-language stub. This could be made faster by
+ * defining a frame_type field in the machine-dependent frame information,
+ * but we don't think that's too important right now.
+ */
+enum frametype { tf_normal, tf_trap, tf_interrupt, tf_syscall };
+
+CORE_ADDR
+fbsd_kern_frame_saved_pc (fr)
+struct frame_info *fr;
+{
+ struct minimal_symbol *sym;
+ CORE_ADDR this_saved_pc;
+ enum frametype frametype;
+
+ this_saved_pc = read_memory_integer (fr->frame + 4, 4);
+ sym = lookup_minimal_symbol_by_pc (this_saved_pc);
+ frametype = tf_normal;
+ if (sym != NULL) {
+ if (strcmp (SYMBOL_NAME(sym), "calltrap") == 0)
+ frametype = tf_trap;
+ else if (strncmp (SYMBOL_NAME(sym), "Xresume", 7) == 0)
+ frametype = tf_interrupt;
+ else if (strcmp (SYMBOL_NAME(sym), "Xsyscall") == 0)
+ frametype = tf_syscall;
+ }
+
+ switch (frametype) {
+ case tf_normal:
+ return (this_saved_pc);
+
+#define oEIP offsetof(struct trapframe, tf_eip)
+
+ case tf_trap:
+ return (read_memory_integer (fr->frame + 8 + oEIP, 4));
+
+ case tf_interrupt:
+ return (read_memory_integer (fr->frame + 16 + oEIP, 4));
+
+ case tf_syscall:
+ return (read_memory_integer (fr->frame + 8 + oEIP, 4));
+#undef oEIP
+ }
+}
+
+CORE_ADDR
+fbsd_kern_frame_chain (fr)
+struct frame_info *fr;
+{
+ struct minimal_symbol *sym;
+ CORE_ADDR this_saved_pc;
+ enum frametype frametype;
+
+ this_saved_pc = read_memory_integer (fr->frame + 4, 4);
+ sym = lookup_minimal_symbol_by_pc (this_saved_pc);
+ frametype = tf_normal;
+ if (sym != NULL) {
+ if (strcmp (SYMBOL_NAME(sym), "calltrap") == 0)
+ frametype = tf_trap;
+ else if (strncmp (SYMBOL_NAME(sym), "Xresume", 7) == 0)
+ frametype = tf_interrupt;
+ else if (strcmp (SYMBOL_NAME(sym), "_Xsyscall") == 0)
+ frametype = tf_syscall;
+ }
+
+ switch (frametype) {
+ case tf_normal:
+ return (read_memory_integer (fr->frame, 4));
+
+#define oEBP offsetof(struct trapframe, tf_ebp)
+
+ case tf_trap:
+ return (read_memory_integer (fr->frame + 8 + oEBP, 4));
+
+ case tf_interrupt:
+ return (read_memory_integer (fr->frame + 16 + oEBP, 4));
+
+ case tf_syscall:
+ return (read_memory_integer (fr->frame + 8 + oEBP, 4));
+#undef oEBP
+ }
+}
+
+static CORE_ADDR
+ksym_lookup (name)
+const char *name;
+{
+ struct minimal_symbol *sym;
+
+ sym = lookup_minimal_symbol (name, NULL, NULL);
+ if (sym == NULL)
+ error ("kernel symbol `%s' not found.", name);
+
+ return SYMBOL_VALUE_ADDRESS (sym);
+}
+
+static struct proc *
+curProc ()
+{
+ struct proc *p;
+ CORE_ADDR addr = ksym_lookup ("curproc");
+
+ if (kvread (addr, &p))
+ error ("cannot read proc pointer at %x\n", addr);
+ return p;
+}
+
+/*
+ * Set the process context to that of the proc structure at
+ * system address paddr.
+ */
+static int
+set_proc_context (paddr)
+ CORE_ADDR paddr;
+{
+ struct proc p;
+
+ if (paddr < kernel_start)
+ return (1);
+
+ cur_proc = (struct proc *)paddr;
+#ifdef notyet
+ set_kernel_boundaries (cur_proc);
+#endif
+
+ /* Fetch all registers from core file */
+ target_fetch_registers (-1);
+
+ /* Now, set up the frame cache, and print the top of stack */
+ flush_cached_frames ();
+ set_current_frame (create_new_frame (read_fp (), read_pc ()));
+ select_frame (get_current_frame (), 0);
+ return (0);
+}
+
+/* Discard all vestiges of any previous core file
+ and mark data and stack spaces as empty. */
+
+/* ARGSUSED */
+static void
+kcore_close (quitting)
+ int quitting;
+{
+ inferior_pid = 0; /* Avoid confusion from thread stuff */
+
+ if (core_kd)
+ {
+ kvm_close (core_kd);
+ free (core_file);
+ core_file = NULL;
+ core_kd = -1;
+ }
+}
+
+/* This routine opens and sets up the core file bfd */
+
+static void
+kcore_open (filename, from_tty)
+ char *filename;
+ int from_tty;
+{
+ const char *p;
+ struct cleanup *old_chain;
+ char buf[256], *cp;
+ int ontop;
+ CORE_ADDR addr;
+ struct pcb pcb;
+
+ target_preopen (from_tty);
+
+ unpush_target (&kcore_ops);
+
+ if (!filename)
+ {
+ /*error (core_kd?*/
+ error ( (core_kd >= 0)?
+ "No core file specified. (Use `detach' to stop debugging a core file.)"
+ : "No core file specified.");
+ }
+
+ filename = tilde_expand (filename);
+ if (filename[0] != '/')
+ {
+ cp = concat (current_directory, "/", filename, NULL);
+ free (filename);
+ filename = cp;
+ }
+
+ old_chain = make_cleanup (free, filename);
+
+ /*
+ * gdb doesn't really do anything if the exec-file couldn't
+ * be opened (in that case exec_bfd is NULL). Usually that's
+ * no big deal, but kvm_open needs the exec-file's name,
+ * which results in dereferencing a NULL pointer, a real NO-NO !
+ * So, check here if the open of the exec-file succeeded.
+ */
+ if (exec_bfd == NULL) /* the open failed */
+ error ("kgdb could not open the exec-file, please check the name you used !");
+
+ core_kd = kvm_open (exec_bfd->filename, filename, NULL,
+ kernel_writablecore? O_RDWR : O_RDONLY, "kgdb: ");
+ if (core_kd < 0)
+ perror_with_name (filename);
+
+ /* Looks semi-reasonable. Toss the old core file and work on the new. */
+
+ discard_cleanups (old_chain); /* Don't free filename any more */
+ core_file = filename;
+ ontop = !push_target (&kcore_ops);
+
+ kernel_start = bfd_get_start_address (exec_bfd); /* XXX */
+
+ /* print out the panic string if there is one */
+ if (kvread (ksym_lookup ("panicstr"), &addr) == 0
+ && addr != 0
+ && target_read_memory (addr, buf, sizeof (buf)) == 0)
+ {
+ for (cp = buf; cp < &buf[sizeof (buf)] && *cp; cp++)
+ if (!isascii (*cp) || (!isprint (*cp) && !isspace (*cp)))
+ *cp = '?';
+ *cp = '\0';
+ if (buf[0] != '\0')
+ printf ("panic: %s\n", buf);
+ }
+
+ if (!ontop)
+ {
+ warning ("you won't be able to access this core file until you terminate\n\
+your %s; do ``info files''", target_longname);
+ return;
+ }
+
+ /* we may need this later */
+ cur_proc = (struct proc *)curProc ();
+ /* Now, set up the frame cache, and print the top of stack */
+ flush_cached_frames ();
+ set_current_frame (create_new_frame (read_fp (), read_pc ()));
+ select_frame (get_current_frame (), 0);
+ print_stack_frame (selected_frame, selected_frame_level, 1);
+}
+
+static void
+kcore_detach (args, from_tty)
+ char *args;
+ int from_tty;
+{
+ if (args)
+ error ("Too many arguments");
+ unpush_target (&kcore_ops);
+ reinit_frame_cache ();
+ if (from_tty)
+ printf_filtered ("No kernel core file now.\n");
+}
+
+/* Get the registers out of a core file. This is the machine-
+ independent part. Fetch_core_registers is the machine-dependent
+ part, typically implemented in the xm-file for each architecture. */
+
+/* We just get all the registers, so we don't use regno. */
+/* ARGSUSED */
+static void
+get_kcore_registers (regno)
+ int regno;
+{
+ struct user *uaddr;
+
+ /* find the pcb for the current process */
+ if (kvread (&cur_proc->p_addr, &uaddr))
+ error ("cannot read u area ptr for proc at %#x", cur_proc);
+ if (read_pcb (core_kd, (CORE_ADDR)&uaddr->u_pcb) < 0)
+ error ("cannot read pcb at %#x", &uaddr->u_pcb);
+}
+
+static void
+kcore_files_info (t)
+ struct target_ops *t;
+{
+ printf ("\t`%s'\n", core_file);
+}
+
+static int
+kcore_xfer_kmem (memaddr, myaddr, len, write, target)
+ CORE_ADDR memaddr;
+ char *myaddr;
+ int len;
+ int write;
+ struct target_ops *target;
+{
+ int n;
+
+ if (!memaddr)
+ return (0);
+
+ if (memaddr < kernel_start)
+ return xfer_umem (memaddr, myaddr, len, write);
+
+ n = write ?
+ kvm_write (core_kd, memaddr, myaddr, len) :
+ kvm_read (core_kd, memaddr, myaddr, len) ;
+
+ if (n < 0)
+ return 0;
+ return n;
+}
+
+static int
+xfer_umem (memaddr, myaddr, len, write)
+ CORE_ADDR memaddr;
+ char *myaddr;
+ int len;
+ int write; /* ignored */
+{
+ int n;
+ struct proc proc;
+
+ if (kvread (cur_proc, &proc))
+ error ("cannot read proc at %#x", cur_proc);
+ n = kvm_uread (core_kd, &proc, memaddr, myaddr, len) ;
+
+ if (n < 0)
+ return 0;
+ return n;
+}
+
+static void
+set_proc_cmd (arg, from_tty)
+ char *arg;
+ int from_tty;
+{
+ CORE_ADDR paddr;
+ struct kinfo_proc *kp;
+ int cnt = 0;
+
+ if (!arg)
+ error_no_arg ("proc address for new current process");
+ if (!kernel_debugging)
+ error ("not debugging kernel");
+
+ paddr = (CORE_ADDR)parse_and_eval_address (arg);
+ /* assume it's a proc pointer if it's in the kernel */
+ if (paddr >= kernel_start) {
+ if (set_proc_context(paddr))
+ error("invalid proc address");
+ } else {
+ kp = kvm_getprocs(core_kd, KERN_PROC_PID, paddr, &cnt);
+ if (!cnt)
+ error("invalid pid");
+ if (set_proc_context((CORE_ADDR)kp->kp_eproc.e_paddr))
+ error("invalid proc address");
+ }
+}
+
+
+
+#define KERNOFF ((unsigned)KERNBASE)
+#define INKERNEL(x) ((x) >= KERNOFF)
+
+static CORE_ADDR sbr;
+static CORE_ADDR curpcb;
+static CORE_ADDR kstack;
+static int found_pcb;
+static int devmem;
+static int kfd;
+static struct pcb pcb;
+
+/* substitutes for the stuff in libkvm which doesn't work */
+/* most of this was taken from the old kgdb */
+
+/* we don't need all this stuff, but the call should look the same */
+
+static int
+kvm_open (efile, cfile, sfile, perm, errout)
+ const char *efile;
+ char *cfile;
+ char *sfile; /* makes this kvm_open more compatible to the one in libkvm */
+ int perm;
+ char *errout; /* makes this kvm_open more compatible to the one in libkvm */
+{
+ struct stat stb;
+ CORE_ADDR addr;
+ int cfd;
+
+ if ((cfd = open (cfile, perm, 0)) < 0)
+ return (cfd);
+
+ fstat (cfd, &stb);
+ if ((stb.st_mode & S_IFMT) == S_IFCHR
+ && stb.st_rdev == makedev (2, 0))
+ {
+ devmem = 1;
+ kfd = open ("/dev/kmem", perm, 0);
+ }
+
+ physrd (cfd, ksym_lookup ("IdlePTD") - KERNOFF, (char*)&sbr, sizeof sbr);
+ printf ("IdlePTD %x\n", sbr);
+ curpcb = ksym_lookup ("curpcb") - KERNOFF;
+ physrd (cfd, curpcb, (char*)&curpcb, sizeof curpcb);
+ kstack = ksym_lookup ("kstack");
+
+ found_pcb = 1; /* for vtophys */
+ if (!devmem)
+ read_pcb (cfd, ksym_lookup ("dumppcb") - KERNOFF);
+ else
+ read_pcb (cfd, kvtophys (cfd, kstack));
+
+ return (cfd);
+}
+
+static int
+kvm_close (fd)
+ int fd;
+{
+ return (close (fd));
+}
+
+static int
+kvm_write (core_kd, memaddr, myaddr, len)
+ int core_kd;
+ CORE_ADDR memaddr;
+ char *myaddr;
+{
+ int cc;
+
+ if (devmem)
+ {
+ if (kfd > 0)
+ {
+ /*
+ * Just like kvm_read, only we write.
+ */
+ errno = 0;
+ if (lseek (kfd, (off_t)memaddr, 0) < 0
+ && errno != 0)
+ {
+ error ("kvm_write:invalid address (%x)", memaddr);
+ return (0);
+ }
+ cc = write (kfd, myaddr, len);
+ if (cc < 0)
+ {
+ error ("kvm_write:write failed");
+ return (0);
+ }
+ else if (cc < len)
+ error ("kvm_write:short write");
+ return (cc);
+ }
+ else
+ return (0);
+ }
+ else
+ {
+ printf ("kvm_write not implemented for dead kernels\n");
+ return (0);
+ }
+ /* NOTREACHED */
+}
+
+static int
+kvm_read (core_kd, memaddr, myaddr, len)
+ int core_kd;
+ CORE_ADDR memaddr;
+ char *myaddr;
+{
+ return (kernel_core_file_hook (core_kd, memaddr, myaddr, len));
+}
+
+static int
+kvm_uread (core_kd, p, memaddr, myaddr, len)
+ int core_kd;
+ register struct proc *p;
+ CORE_ADDR memaddr;
+ char *myaddr;
+ int len;
+{
+ register char *cp;
+ char procfile[MAXPATHLEN];
+ ssize_t amount;
+ int fd;
+
+ if (devmem)
+ {
+ cp = myaddr;
+
+ sprintf (procfile, "/proc/%d/mem", p->p_pid);
+ fd = open (procfile, O_RDONLY, 0);
+
+ if (fd < 0)
+ {
+ error ("cannot open %s", procfile);
+ close (fd);
+ return (0);
+ }
+
+ while (len > 0)
+ {
+ if (lseek (fd, memaddr, 0) == -1 && errno != 0)
+ {
+ error ("invalid address (%x) in %s",
+ memaddr, procfile);
+ break;
+ }
+ amount = read (fd, cp, len);
+ if (amount < 0)
+ {
+ error ("error reading %s", procfile);
+ break;
+ }
+ cp += amount;
+ memaddr += amount;
+ len -= amount;
+ }
+
+ close (fd);
+ return (ssize_t) (cp - myaddr);
+ }
+ else
+ return (kernel_core_file_hook (core_kd, memaddr, myaddr, len));
+}
+
+static struct kinfo_proc kp;
+
+/*
+ * try to do what kvm_proclist in libkvm would do
+ */
+static int
+kvm_proclist (cfd, pid, p, cnt)
+int cfd, pid, *cnt;
+struct proc *p;
+{
+ struct proc lp;
+
+ for (; p != NULL; p = lp.p_list.le_next) {
+ if (!kvm_read(cfd, (CORE_ADDR)p, (char *)&lp, sizeof (lp)))
+ return (0);
+ if (lp.p_pid != pid)
+ continue;
+ kp.kp_eproc.e_paddr = p;
+ *cnt = 1;
+ return (1);
+ }
+ *cnt = 0;
+ return (0);
+}
+
+/*
+ * try to do what kvm_deadprocs in libkvm would do
+ */
+static struct kinfo_proc *
+kvm_deadprocs (cfd, pid, cnt)
+int cfd, pid, *cnt;
+{
+ CORE_ADDR allproc, zombproc;
+ struct proc *p;
+
+ allproc = ksym_lookup("allproc");
+ if (kvm_read(cfd, allproc, (char *)&p, sizeof (p)) == 0)
+ return (NULL);
+ kvm_proclist (cfd, pid, p, cnt);
+ if (!*cnt) {
+ zombproc = ksym_lookup("zombproc");
+ if (kvm_read(cfd, zombproc, (char *)&p, sizeof (p)) == 0)
+ return (NULL);
+ kvm_proclist (cfd, pid, p, cnt);
+ }
+ return (&kp);
+}
+
+/*
+ * try to do what kvm_getprocs in libkvm would do
+ */
+static struct kinfo_proc *
+kvm_getprocs (cfd, op, proc, cnt)
+int cfd, op, *cnt;
+CORE_ADDR proc;
+{
+ int mib[4], size;
+
+ *cnt = 0;
+ /* assume it's a pid */
+ if (devmem) { /* "live" kernel, use sysctl */
+ mib[0] = CTL_KERN;
+ mib[1] = KERN_PROC;
+ mib[2] = KERN_PROC_PID;
+ mib[3] = (int)proc;
+ size = sizeof (kp);
+ if (sysctl (mib, 4, &kp, &size, NULL, 0) < 0) {
+ perror("sysctl");
+ *cnt = 0;
+ return (NULL);
+ }
+ if (!size)
+ *cnt = 0;
+ else
+ *cnt = 1;
+ return (&kp);
+ } else
+ return (kvm_deadprocs (cfd, (int)proc, cnt));
+}
+
+static int
+physrd (cfd, addr, dat, len)
+ int cfd;
+ u_int addr;
+ char *dat;
+ int len;
+{
+ if (lseek (cfd, (off_t)addr, L_SET) == -1)
+ return (-1);
+ return (read (cfd, dat, len));
+}
+
+static CORE_ADDR
+kvtophys (fd, addr)
+ int fd;
+ CORE_ADDR addr;
+{
+ CORE_ADDR v;
+ unsigned int pte;
+ static CORE_ADDR PTD = -1;
+ CORE_ADDR current_ptd;
+
+ /*
+ * If we're looking at the kernel stack,
+ * munge the address to refer to the user space mapping instead;
+ * that way we get the requested process's kstack, not the running one.
+ */
+ /*
+ * this breaks xlating user addresses from a crash dump so only
+ * do it for a "live" kernel.
+ */
+ if (devmem && addr >= kstack && addr < kstack + ctob (UPAGES))
+ addr = (addr - kstack) + curpcb;
+
+ /*
+ * We may no longer have a linear system page table...
+ *
+ * Here's the scoop. IdlePTD contains the physical address
+ * of a page table directory that always maps the kernel.
+ * IdlePTD is in memory that is mapped 1-to-1, so we can
+ * find it easily given its 'virtual' address from ksym_lookup().
+ * For hysterical reasons, the value of IdlePTD is stored in sbr.
+ *
+ * To look up a kernel address, we first convert it to a 1st-level
+ * address and look it up in IdlePTD. This gives us the physical
+ * address of a page table page; we extract the 2nd-level part of
+ * VA and read the 2nd-level pte. Finally, we add the offset part
+ * of the VA into the physical address from the pte and return it.
+ *
+ * User addresses are a little more complicated. If we don't have
+ * a current PCB from read_pcb(), we use PTD, which is the (fixed)
+ * virtual address of the current ptd. Since it's NOT in 1-to-1
+ * kernel space, we must look it up using IdlePTD. If we do have
+ * a pcb, we get the ptd from pcb_ptd.
+ */
+
+ if (INKERNEL (addr))
+ current_ptd = sbr;
+ else if (found_pcb == 0)
+ {
+ if (PTD == -1)
+ PTD = kvtophys (fd, ksym_lookup ("PTD"));
+ current_ptd = PTD;
+ }
+ else
+ current_ptd = pcb.pcb_cr3;
+
+ /*
+ * Read the first-level page table (ptd).
+ */
+ v = current_ptd + ( (unsigned)addr >> PDRSHIFT) * sizeof pte;
+ if (physrd (fd, v, (char *)&pte, sizeof pte) < 0 || (pte&PG_V) == 0)
+ return (~0);
+
+ /*
+ * Read the second-level page table.
+ */
+ v = (pte&PG_FRAME) + ((addr >> PAGE_SHIFT)&(NPTEPG-1)) * sizeof pte;
+ if (physrd (fd, v, (char *) &pte, sizeof (pte)) < 0 || (pte&PG_V) == 0)
+ return (~0);
+
+ addr = (pte & PG_FRAME) + (addr & PAGE_MASK);
+#if 0
+ printf ("vtophys (%x) -> %x\n", oldaddr, addr);
+#endif
+ return (addr);
+}
+
+static int
+read_pcb (fd, uaddr)
+ int fd;
+ CORE_ADDR uaddr;
+{
+ int i;
+ int *pcb_regs = (int *)&pcb;
+ int eip;
+ CORE_ADDR nuaddr = uaddr;
+
+ /* need this for the `proc' command to work */
+ if (INKERNEL(uaddr))
+ nuaddr = kvtophys(fd, uaddr);
+
+ if (physrd (fd, nuaddr, (char *)&pcb, sizeof pcb) < 0)
+ {
+ error ("cannot read pcb at %x\n", uaddr);
+ return (-1);
+ }
+ printf ("current pcb at %x\n", uaddr);
+
+ /*
+ * get the register values out of the sys pcb and
+ * store them where `read_register' will find them.
+ */
+ for (i = 0; i < 8; ++i)
+ supply_register (i, (char *)&pcb_regs[i+10]);
+ supply_register (8, (char *)&pcb_regs[8]); /* eip */
+ supply_register (9, (char *)&pcb_regs[9]); /* eflags */
+ for (i = 10; i < 13; ++i) /* cs, ss, ds */
+ supply_register (i, (char *)&pcb_regs[i+9]);
+ supply_register (13, (char *)&pcb_regs[18]); /* es */
+ for (i = 14; i < 16; ++i) /* fs, gs */
+ supply_register (i, (char *)&pcb_regs[i+8]);
+
+#if 0 /* doesn't work ??? */
+ /* Hmm... */
+ if (target_read_memory (pcb_regs[5+10]+4, &eip, sizeof eip, 0))
+ error ("Cannot read PC.");
+ supply_register (8, (char *)&eip); /* eip */
+#endif
+
+ /* XXX 80387 registers? */
+}
+
+/*
+ * read len bytes from kernel virtual address 'addr' into local
+ * buffer 'buf'. Return numbert of bytes if read ok, 0 otherwise. On read
+ * errors, portion of buffer not read is zeroed.
+ */
+
+static int
+kernel_core_file_hook (fd, addr, buf, len)
+ int fd;
+ CORE_ADDR addr;
+ char *buf;
+ int len;
+{
+ int i;
+ CORE_ADDR paddr;
+ register char *cp;
+ int cc;
+
+ cp = buf;
+
+ while (len > 0)
+ {
+ paddr = kvtophys (fd, addr);
+ if (paddr == ~0)
+ {
+ memset (buf, '\000', len);
+ break;
+ }
+ /* we can't read across a page boundary */
+ i = min (len, PAGE_SIZE - (addr & PAGE_MASK));
+ if ( (cc = physrd (fd, paddr, cp, i)) <= 0)
+ {
+ memset (cp, '\000', len);
+ return (cp - buf);
+ }
+ cp += cc;
+ addr += cc;
+ len -= cc;
+ }
+ return (cp - buf);
+}
+
+struct target_ops kcore_ops = {
+ "kcore", /* to_shortname */
+ "Kernel core dump file", /* to_longname */
+ "Use a core file as a target. Specify the filename of the core file.", /* to_doc */
+ kcore_open, /* to_open */
+ kcore_close, /* to_close */
+ find_default_attach, /* to_attach */
+ kcore_detach, /* to_detach */
+ NULL, /* to_resume */
+ NULL, /* to_wait */
+ get_kcore_registers, /* to_fetch_registers */
+ NULL, /* to_store_registers */
+ NULL, /* to_prepare_to_store */
+ kcore_xfer_kmem, /* to_xfer_memory */
+ kcore_files_info, /* to_files_info */
+ NULL, /* to_insert_breakpoint */
+ NULL, /* to_remove_breakpoint */
+ NULL, /* to_terminal_init */
+ NULL, /* to_terminal_inferior */
+ NULL, /* to_terminal_ours_for_output */
+ NULL, /* to_terminal_ours */
+ NULL, /* to_terminal_info */
+ NULL, /* to_kill */
+ NULL, /* to_load */
+ NULL, /* to_lookup_symbol */
+ find_default_create_inferior, /* to_create_inferior */
+ NULL, /* to_mourn_inferior */
+ 0, /* to_can_run */
+ 0, /* to_notice_signals */
+ NULL, /* to_thread_alive */
+ 0, /* to_stop */
+ kcore_stratum, /* to_stratum */
+ NULL, /* to_next */
+ 0, /* to_has_all_memory */
+ 1, /* to_has_memory */
+ 1, /* to_has_stack */
+ 1, /* to_has_registers */
+ 0, /* to_has_execution */
+ NULL, /* sections */
+ NULL, /* sections_end */
+ OPS_MAGIC /* to_magic */
+};
+
+void
+_initialize_kcorelow()
+{
+ add_target (&kcore_ops);
+ add_com ("proc", class_obscure, set_proc_cmd, "Set current process context");
+}
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