Add support for virtual cores (aka minidumps). To that end, refactor this

file as follows:
1.  Common ia64-specific support functions have the ia64_ prefix.
2.  Functions that work on physical cores have the phys_ prefix.
3.  Functions that work on virtual cores have the virt_ prefix.

With that:
1.  _kvm_kvatop() has been renamed to phys_kvatop() as it handles
    physical cores only.
2.  The new _kvm_kvatop() is nothing but a wrapper that calls either
    phys_kvatop() or virt_kvatop() by virtue of the kvatop function
    pointer in the vmstate structure.
3.  virt_kvatop() is nothing but a wrapper around virt_addr2off().
4.  virt_addr2off() iterates over the Phdrs to find the segment in
    which the address falls and return the file offset for it.

Now it's up to the kernel to populate the core file appropriately.

1 files changed, 141 insertions, 72 deletions

diff --git a/lib/libkvm/kvm_ia64.c b/lib/libkvm/kvm_ia64.c
index 2977e9f..109cc14 100644
--- a/lib/libkvm/kvm_ia64.c
+++ b/lib/libkvm/kvm_ia64.c
@@ -35,15 +35,18 @@
 #ifndef CROSS_LIBKVM
 #include <machine/atomic.h>
 #include <machine/bootinfo.h>
+#include <machine/elf.h>
 #include <machine/pte.h>
 #else
 #include "../../sys/ia64/include/atomic.h"
 #include "../../sys/ia64/include/bootinfo.h"
+#include "../../sys/ia64/include/elf.h"
 #include "../../sys/ia64/include/pte.h"
 #endif
 
 #include <kvm.h>
 #include <limits.h>
+#include <stdint.h>
 #include <stdlib.h>
 #include <unistd.h>
 
@@ -61,6 +64,8 @@
 #define	PBVM_BASE		0x9ffc000000000000UL
 #define	PBVM_PGSZ		(64 * 1024)
 
+typedef size_t (a2p_f)(kvm_t *, uint64_t, off_t *);
+
 struct vmstate {
 	void	*mmapbase;
 	size_t	mmapsize;
@@ -68,6 +73,7 @@ struct vmstate {
 	u_long	kptdir;
 	u_long	*pbvm_pgtbl;
 	u_int	pbvm_pgtblsz;
+	a2p_f	*kvatop;
 };
 
 /*
@@ -76,7 +82,7 @@ struct vmstate {
  * set of headers.
  */
 static int
-_kvm_maphdrs(kvm_t *kd, size_t sz)
+ia64_maphdrs(kvm_t *kd, size_t sz)
 {
 	struct vmstate *vm = kd->vmst;
 
@@ -97,18 +103,22 @@ _kvm_maphdrs(kvm_t *kd, size_t sz)
 }
 
 /*
- * Translate a physical memory address to a file-offset in the crash-dump.
+ * Physical core support.
  */
+
 static size_t
-_kvm_pa2off(kvm_t *kd, uint64_t pa, off_t *ofs, size_t pgsz)
+phys_addr2off(kvm_t *kd, uint64_t pa, off_t *ofs, size_t pgsz)
 {
-	Elf64_Ehdr *e = kd->vmst->mmapbase;
-	Elf64_Phdr *p = (Elf64_Phdr*)((char*)e + e->e_phoff);
-	int n = e->e_phnum;
+	Elf64_Ehdr *e;
+	Elf64_Phdr *p;
+	int n;
 
 	if (pa != REGION_ADDR(pa))
 		goto fail;
 
+	e = (Elf64_Ehdr *)(kd->vmst->mmapbase);
+	n = e->e_phnum;
+	p = (Elf64_Phdr *)(void *)((uintptr_t)(void *)e + e->e_phoff);
 	while (n && (pa < p->p_paddr || pa >= p->p_paddr + p->p_memsz))
 		p++, n--;
 	if (n == 0)
@@ -120,18 +130,76 @@ _kvm_pa2off(kvm_t *kd, uint64_t pa, off_t *ofs, size_t pgsz)
 	return (pgsz - ((size_t)pa & (pgsz - 1)));
 
  fail:
-	_kvm_err(kd, kd->program, "invalid physical address %#llx",
-	    (unsigned long long)pa);
+	_kvm_err(kd, kd->program, "invalid physical address %#jx",
+	    (uintmax_t)pa);
+	return (0);
+}
+
+static size_t
+phys_kvatop(kvm_t *kd, uint64_t va, off_t *ofs)
+{
+	struct ia64_lpte pte;
+	uint64_t pa, pgaddr, pt0addr, pt1addr;
+	size_t pgno, pgsz, pt0no, pt1no;
+
+	if (va >= REGION_BASE(6)) {
+		/* Regions 6 and 7: direct mapped. */
+		pa = REGION_ADDR(va);
+		return (phys_addr2off(kd, pa, ofs, 0));
+	} else if (va >= REGION_BASE(5)) {
+		/* Region 5: Kernel Virtual Memory. */
+		va = REGION_ADDR(va);
+		pgsz = kd->vmst->pagesize;
+		pt0no = KPTE_DIR0_INDEX(va, pgsz);
+		pt1no = KPTE_DIR1_INDEX(va, pgsz);
+		pgno = KPTE_PTE_INDEX(va, pgsz);
+		if (pt0no >= NKPTEDIR(pgsz))
+			goto fail;
+		pt0addr = kd->vmst->kptdir + (pt0no << 3);
+		if (kvm_read(kd, pt0addr, &pt1addr, 8) != 8)
+			goto fail;
+		if (pt1addr == 0)
+			goto fail;
+		pt1addr += pt1no << 3;
+		if (kvm_read(kd, pt1addr, &pgaddr, 8) != 8)
+			goto fail;
+		if (pgaddr == 0)
+			goto fail;
+		pgaddr += pgno * sizeof(pte);
+		if (kvm_read(kd, pgaddr, &pte, sizeof(pte)) != sizeof(pte))
+			goto fail;
+		if (!(pte.pte & PTE_PRESENT))
+			goto fail;
+		pa = (pte.pte & PTE_PPN_MASK) + (va & (pgsz - 1));
+		return (phys_addr2off(kd, pa, ofs, pgsz));
+	} else if (va >= PBVM_BASE) {
+		/* Region 4: Pre-Boot Virtual Memory (PBVM). */
+		va -= PBVM_BASE;
+		pgsz = PBVM_PGSZ;
+		pt0no = va / pgsz;
+		if (pt0no >= (kd->vmst->pbvm_pgtblsz >> 3))
+			goto fail;
+		pt0addr = kd->vmst->pbvm_pgtbl[pt0no];
+		if (!(pt0addr & PTE_PRESENT))
+			goto fail;
+		pa = (pt0addr & PTE_PPN_MASK) + va % pgsz;
+		return (phys_addr2off(kd, pa, ofs, pgsz));
+	}
+
+ fail:
+	_kvm_err(kd, kd->program, "invalid kernel virtual address %#jx",
+	    (uintmax_t)va);
+	*ofs = -1;
 	return (0);
 }
 
 static ssize_t
-_kvm_read_phys(kvm_t *kd, uint64_t pa, void *buf, size_t bufsz)
+phys_read(kvm_t *kd, uint64_t pa, void *buf, size_t bufsz)
 {
 	off_t ofs;
 	size_t sz;
 
-	sz = _kvm_pa2off(kd, pa, &ofs, 0);
+	sz = phys_addr2off(kd, pa, &ofs, 0);
 	if (sz < bufsz)
 		return ((ssize_t)sz);
 
@@ -140,6 +208,50 @@ _kvm_read_phys(kvm_t *kd, uint64_t pa, void *buf, size_t bufsz)
 	return (read(kd->pmfd, buf, bufsz));
 }
 
+/*
+ * Virtual core support (aka minidump).
+ */
+
+static size_t
+virt_addr2off(kvm_t *kd, uint64_t va, off_t *ofs, size_t pgsz)
+{
+	Elf64_Ehdr *e;
+	Elf64_Phdr *p;
+	int n;
+
+	if (va < REGION_BASE(4))
+		goto fail;
+
+	e = (Elf64_Ehdr *)(kd->vmst->mmapbase);
+	n = e->e_phnum;
+	p = (Elf64_Phdr *)(void *)((uintptr_t)(void *)e + e->e_phoff); 
+	while (n && (va < p->p_vaddr || va >= p->p_vaddr + p->p_memsz))
+		p++, n--;
+	if (n == 0)
+		goto fail;
+
+	*ofs = (va - p->p_vaddr) + p->p_offset;
+	if (pgsz == 0)
+		return (p->p_memsz - (va - p->p_vaddr));
+	return (pgsz - ((size_t)va & (pgsz - 1)));
+
+ fail:
+	_kvm_err(kd, kd->program, "invalid virtual address %#jx",
+	    (uintmax_t)va);
+	return (0);
+}
+
+static size_t
+virt_kvatop(kvm_t *kd, uint64_t va, off_t *ofs)
+{
+
+	return (virt_addr2off(kd, va, ofs, kd->vmst->pagesize));
+}
+
+/*
+ * KVM architecture support functions.
+ */
+
 void
 _kvm_freevtop(kvm_t *kd)
 {
@@ -175,25 +287,31 @@ _kvm_initvtop(kvm_t *kd)
 	kd->vmst->pagesize = 8192;
 #endif
 
-	if (_kvm_maphdrs(kd, sizeof(Elf64_Ehdr)) == -1)
+	if (ia64_maphdrs(kd, sizeof(Elf64_Ehdr)) == -1)
 		return (-1);
 
 	ehdr = kd->vmst->mmapbase;
 	hdrsz = ehdr->e_phoff + ehdr->e_phentsize * ehdr->e_phnum;
-	if (_kvm_maphdrs(kd, hdrsz) == -1)
+	if (ia64_maphdrs(kd, hdrsz) == -1)
 		return (-1);
 
+	kd->vmst->kvatop = (ehdr->e_flags & EF_IA_64_ABSOLUTE) ?
+	    phys_kvatop : virt_kvatop;
+
 	/*
 	 * Load the PBVM page table. We need this to resolve PBVM addresses.
 	 * The PBVM page table is obtained from the bootinfo structure, of
-	 * which the physical address is given to us in e_entry. If e_entry
-	 * is 0, then this is assumed to be a pre-PBVM kernel.
+	 * which the address is given to us in e_entry. If e_entry is 0, then
+	 * this is assumed to be a pre-PBVM kernel.
+	 * Note that the address of the bootinfo structure is either physical
+	 * or virtual, depending on whether the core is physical or virtual.
 	 */
-	if (ehdr->e_entry != 0) {
-		sz = _kvm_read_phys(kd, ehdr->e_entry, &bi, sizeof(bi));
+	if (ehdr->e_entry != 0 && (ehdr->e_flags & EF_IA_64_ABSOLUTE) != 0) {
+		sz = phys_read(kd, ehdr->e_entry, &bi, sizeof(bi));
 		if (sz != sizeof(bi)) {
 			_kvm_err(kd, kd->program,
-			    "cannot read bootinfo from PA %#lx", ehdr->e_entry);
+			    "cannot read bootinfo at physical address %#jx",
+			    (uintmax_t)ehdr->e_entry);
 			return (-1);
 		}
 		if (bi.bi_magic != BOOTINFO_MAGIC) {
@@ -206,12 +324,12 @@ _kvm_initvtop(kvm_t *kd)
 			return (-1);
 		}
 		kd->vmst->pbvm_pgtblsz = bi.bi_pbvm_pgtblsz;
-		sz = _kvm_read_phys(kd, bi.bi_pbvm_pgtbl, kd->vmst->pbvm_pgtbl,
+		sz = phys_read(kd, bi.bi_pbvm_pgtbl, kd->vmst->pbvm_pgtbl,
 		    bi.bi_pbvm_pgtblsz);
 		if (sz != bi.bi_pbvm_pgtblsz) {
 			_kvm_err(kd, kd->program,
-			    "cannot read page table from PA %#lx",
-			    bi.bi_pbvm_pgtbl);
+			    "cannot read page table at physical address %#jx",
+			    (uintmax_t)bi.bi_pbvm_pgtbl);
 			return (-1);
 		}
 	} else {
@@ -250,57 +368,8 @@ _kvm_initvtop(kvm_t *kd)
 int
 _kvm_kvatop(kvm_t *kd, u_long va, off_t *ofs)
 {
-	struct ia64_lpte pte;
-	uint64_t pa, pgaddr, pt0addr, pt1addr;
-	size_t pgno, pgsz, pt0no, pt1no;
-
-	if (va >= REGION_BASE(6)) {
-		/* Regions 6 and 7: direct mapped. */
-		pa = REGION_ADDR(va);
-		return (_kvm_pa2off(kd, pa, ofs, 0));
-	} else if (va >= REGION_BASE(5)) {
-		/* Region 5: Kernel Virtual Memory. */
-		va = REGION_ADDR(va);
-		pgsz = kd->vmst->pagesize;
-		pt0no = KPTE_DIR0_INDEX(va, pgsz);
-		pt1no = KPTE_DIR1_INDEX(va, pgsz);
-		pgno = KPTE_PTE_INDEX(va, pgsz);
-		if (pt0no >= NKPTEDIR(pgsz))
-			goto fail;
-		pt0addr = kd->vmst->kptdir + (pt0no << 3);
-		if (kvm_read(kd, pt0addr, &pt1addr, 8) != 8)
-			goto fail;
-		if (pt1addr == 0)
-			goto fail;
-		pt1addr += pt1no << 3;
-		if (kvm_read(kd, pt1addr, &pgaddr, 8) != 8)
-			goto fail;
-		if (pgaddr == 0)
-			goto fail;
-		pgaddr += pgno * sizeof(pte);
-		if (kvm_read(kd, pgaddr, &pte, sizeof(pte)) != sizeof(pte))
-			goto fail;
-		if (!(pte.pte & PTE_PRESENT))
-			goto fail;
-		pa = (pte.pte & PTE_PPN_MASK) + (va & (pgsz - 1));
-		return (_kvm_pa2off(kd, pa, ofs, pgsz));
-	} else if (va >= PBVM_BASE) {
-		/* Region 4: Pre-Boot Virtual Memory (PBVM). */
-		va -= PBVM_BASE;
-		pgsz = PBVM_PGSZ;
-		pt0no = va / pgsz;
-		if (pt0no >= (kd->vmst->pbvm_pgtblsz >> 3))
-			goto fail;
-		pt0addr = kd->vmst->pbvm_pgtbl[pt0no];
-		if (!(pt0addr & PTE_PRESENT))
-			goto fail;
-		pa = (pt0addr & PTE_PPN_MASK) + va % pgsz;
-		return (_kvm_pa2off(kd, pa, ofs, pgsz));
-	}
+	size_t sz;
 
- fail:
-	_kvm_err(kd, kd->program, "invalid kernel virtual address %#llx",
-	    (unsigned long long)va);
-	*ofs = ~0UL;
-	return (0);
+	sz = kd->vmst->kvatop(kd, va, ofs);
+	return (sz);
 }