Page MenuHomeFreeBSD
Files F140785715

D22142.diff
No OneTemporary
Actions

D22142.diff
View Options

Index: head/sys/arm64/arm64/pmap.c
===================================================================
--- head/sys/arm64/arm64/pmap.c
+++ head/sys/arm64/arm64/pmap.c
@@ -121,6 +121,7 @@
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/rwlock.h>
+#include <sys/sbuf.h>
#include <sys/sx.h>
#include <sys/vmem.h>
#include <sys/vmmeter.h>
@@ -6156,3 +6157,212 @@
return (mode >= VM_MEMATTR_DEVICE && mode <= VM_MEMATTR_WRITE_THROUGH);
}
+
+/*
+ * Track a range of the kernel's virtual address space that is contiguous
+ * in various mapping attributes.
+ */
+struct pmap_kernel_map_range {
+ vm_offset_t sva;
+ pt_entry_t attrs;
+ int l3pages;
+ int l3contig;
+ int l2blocks;
+ int l1blocks;
+};
+
+static void
+sysctl_kmaps_dump(struct sbuf *sb, struct pmap_kernel_map_range *range,
+ vm_offset_t eva)
+{
+ const char *mode;
+ int index;
+
+ if (eva <= range->sva)
+ return;
+
+ index = range->attrs & ATTR_IDX_MASK;
+ switch (index) {
+ case ATTR_IDX(VM_MEMATTR_DEVICE):
+ mode = "DEV";
+ break;
+ case ATTR_IDX(VM_MEMATTR_UNCACHEABLE):
+ mode = "UC";
+ break;
+ case ATTR_IDX(VM_MEMATTR_WRITE_BACK):
+ mode = "WB";
+ break;
+ case ATTR_IDX(VM_MEMATTR_WRITE_THROUGH):
+ mode = "WT";
+ break;
+ default:
+ printf(
+ "%s: unknown memory type %x for range 0x%016lx-0x%016lx\n",
+ __func__, index, range->sva, eva);
+ mode = "??";
+ break;
+ }
+
+ sbuf_printf(sb, "0x%016lx-0x%016lx r%c%c%c %3s %d %d %d %d\n",
+ range->sva, eva,
+ (range->attrs & ATTR_AP_RW_BIT) == ATTR_AP_RW ? 'w' : '-',
+ (range->attrs & ATTR_PXN) != 0 ? '-' : 'x',
+ (range->attrs & ATTR_AP_USER) != 0 ? 'u' : 's',
+ mode, range->l1blocks, range->l2blocks, range->l3contig,
+ range->l3pages);
+
+ /* Reset to sentinel value. */
+ range->sva = 0xfffffffffffffffful;
+}
+
+/*
+ * Determine whether the attributes specified by a page table entry match those
+ * being tracked by the current range.
+ */
+static bool
+sysctl_kmaps_match(struct pmap_kernel_map_range *range, pt_entry_t attrs)
+{
+
+ return (range->attrs == attrs);
+}
+
+static void
+sysctl_kmaps_reinit(struct pmap_kernel_map_range *range, vm_offset_t va,
+ pt_entry_t attrs)
+{
+
+ memset(range, 0, sizeof(*range));
+ range->sva = va;
+ range->attrs = attrs;
+}
+
+/*
+ * Given a leaf PTE, derive the mapping's attributes. If they do not match
+ * those of the current run, dump the address range and its attributes, and
+ * begin a new run.
+ */
+static void
+sysctl_kmaps_check(struct sbuf *sb, struct pmap_kernel_map_range *range,
+ vm_offset_t va, pd_entry_t l0e, pd_entry_t l1e, pd_entry_t l2e,
+ pt_entry_t l3e)
+{
+ pt_entry_t attrs;
+
+ attrs = l0e & (ATTR_AP_MASK | ATTR_XN);
+ attrs |= l1e & (ATTR_AP_MASK | ATTR_XN);
+ if ((l1e & ATTR_DESCR_MASK) == L1_BLOCK)
+ attrs |= l1e & ATTR_IDX_MASK;
+ attrs |= l2e & (ATTR_AP_MASK | ATTR_XN);
+ if ((l2e & ATTR_DESCR_MASK) == L2_BLOCK)
+ attrs |= l2e & ATTR_IDX_MASK;
+ attrs |= l3e & (ATTR_AP_MASK | ATTR_XN | ATTR_IDX_MASK);
+
+ if (range->sva > va || !sysctl_kmaps_match(range, attrs)) {
+ sysctl_kmaps_dump(sb, range, va);
+ sysctl_kmaps_reinit(range, va, attrs);
+ }
+}
+
+static int
+sysctl_kmaps(SYSCTL_HANDLER_ARGS)
+{
+ struct pmap_kernel_map_range range;
+ struct sbuf sbuf, *sb;
+ pd_entry_t l0e, *l1, l1e, *l2, l2e;
+ pt_entry_t *l3, l3e;
+ vm_offset_t sva;
+ vm_paddr_t pa;
+ int error, i, j, k, l;
+
+ error = sysctl_wire_old_buffer(req, 0);
+ if (error != 0)
+ return (error);
+ sb = &sbuf;
+ sbuf_new_for_sysctl(sb, NULL, PAGE_SIZE, req);
+
+ /* Sentinel value. */
+ range.sva = 0xfffffffffffffffful;
+
+ /*
+ * Iterate over the kernel page tables without holding the kernel pmap
+ * lock. Kernel page table pages are never freed, so at worst we will
+ * observe inconsistencies in the output.
+ */
+ for (sva = 0xffff000000000000ul, i = pmap_l0_index(sva); i < Ln_ENTRIES;
+ i++) {
+ if (i == pmap_l0_index(DMAP_MIN_ADDRESS))
+ sbuf_printf(sb, "\nDirect map:\n");
+ else if (i == pmap_l0_index(VM_MIN_KERNEL_ADDRESS))
+ sbuf_printf(sb, "\nKernel map:\n");
+
+ l0e = kernel_pmap->pm_l0[i];
+ if ((l0e & ATTR_DESCR_VALID) == 0) {
+ sysctl_kmaps_dump(sb, &range, sva);
+ sva += L0_SIZE;
+ continue;
+ }
+ pa = l0e & ~ATTR_MASK;
+ l1 = (pd_entry_t *)PHYS_TO_DMAP(pa);
+
+ for (j = pmap_l1_index(sva); j < Ln_ENTRIES; j++) {
+ l1e = l1[j];
+ if ((l1e & ATTR_DESCR_VALID) == 0) {
+ sysctl_kmaps_dump(sb, &range, sva);
+ sva += L1_SIZE;
+ continue;
+ }
+ if ((l1e & ATTR_DESCR_MASK) == L1_BLOCK) {
+ sysctl_kmaps_check(sb, &range, sva, l0e, l1e,
+ 0, 0);
+ range.l1blocks++;
+ sva += L1_SIZE;
+ continue;
+ }
+ pa = l1e & ~ATTR_MASK;
+ l2 = (pd_entry_t *)PHYS_TO_DMAP(pa);
+
+ for (k = pmap_l2_index(sva); k < Ln_ENTRIES; k++) {
+ l2e = l2[k];
+ if ((l2e & ATTR_DESCR_VALID) == 0) {
+ sysctl_kmaps_dump(sb, &range, sva);
+ sva += L2_SIZE;
+ continue;
+ }
+ if ((l2e & ATTR_DESCR_MASK) == L2_BLOCK) {
+ sysctl_kmaps_check(sb, &range, sva,
+ l0e, l1e, l2e, 0);
+ range.l2blocks++;
+ sva += L2_SIZE;
+ continue;
+ }
+ pa = l2e & ~ATTR_MASK;
+ l3 = (pt_entry_t *)PHYS_TO_DMAP(pa);
+
+ for (l = pmap_l3_index(sva); l < Ln_ENTRIES;
+ l++, sva += L3_SIZE) {
+ l3e = l3[l];
+ if ((l3e & ATTR_DESCR_VALID) == 0) {
+ sysctl_kmaps_dump(sb, &range,
+ sva);
+ continue;
+ }
+ sysctl_kmaps_check(sb, &range, sva,
+ l0e, l1e, l2e, l3e);
+ if ((l3e & ATTR_CONTIGUOUS) != 0)
+ range.l3contig += l % 16 == 0 ?
+ 1 : 0;
+ else
+ range.l3pages++;
+ }
+ }
+ }
+ }
+
+ error = sbuf_finish(sb);
+ sbuf_delete(sb);
+ return (error);
+}
+SYSCTL_OID(_vm_pmap, OID_AUTO, kernel_maps,
+ CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
+ NULL, 0, sysctl_kmaps, "A",
+ "Dump kernel address layout");

File Metadata

Mime Type
text/plain
Expires
Mon, Dec 29, 12:46 AM (7 h, 17 m)
Storage Engine
blob
Storage Format
Raw Data
Storage Handle
27327076
Default Alt Text
D22142.diff (5 KB)

Event Timeline