[src/trunk]: src/lib/libnvmm Change the map/unmap functions, again.

[maxv <maxv%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/8233fb891635
branches:  trunk
changeset: 995222:8233fb891635
user:      maxv <maxv%NetBSD.org@localhost>
date:      Wed Dec 12 10:42:34 2018 +0000

description:
Change the map/unmap functions, again.

diffstat:

 lib/libnvmm/libnvmm.c |  147 ++++++++++++++++++++++---------------------------
 1 files changed, 66 insertions(+), 81 deletions(-)

diffs (199 lines):

diff -r 50fd215afdf5 -r 8233fb891635 lib/libnvmm/libnvmm.c
--- a/lib/libnvmm/libnvmm.c     Wed Dec 12 10:25:29 2018 +0000
+++ b/lib/libnvmm/libnvmm.c     Wed Dec 12 10:42:34 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: libnvmm.c,v 1.3 2018/11/29 19:55:20 maxv Exp $ */
+/*     $NetBSD: libnvmm.c,v 1.4 2018/12/12 10:42:34 maxv Exp $ */
 
 /*
  * Copyright (c) 2018 The NetBSD Foundation, Inc.
@@ -57,89 +57,40 @@
 
 /* -------------------------------------------------------------------------- */
 
-static int
-__area_unmap(struct nvmm_machine *mach, uintptr_t hva, gpaddr_t gpa,
- size_t size)
-{
-       struct nvmm_ioc_gpa_unmap args;
-       int ret;
-
-       args.machid = mach->machid;
-       args.gpa = gpa;
-       args.size = size;
-
-       ret = ioctl(nvmm_fd, NVMM_IOC_GPA_UNMAP, &args);
-       if (ret == -1)
-               return -1;
-
-       ret = munmap((void *)hva, size);
-
-       return ret;
-}
-
-static int
-__area_dig_hole(struct nvmm_machine *mach, uintptr_t hva, gpaddr_t gpa,
+static bool
+__area_isvalid(struct nvmm_machine *mach, uintptr_t hva, gpaddr_t gpa,
     size_t size)
 {
        area_list_t *areas = mach->areas;
-       area_t *ent, *tmp, *nxt;
-       size_t diff;
+       area_t *ent;
 
-       LIST_FOREACH_SAFE(ent, areas, list, nxt) {
-               /* Case 1. */
-               if ((gpa < ent->gpa) && (gpa + size > ent->gpa)) {
-                       diff = (gpa + size) - ent->gpa;
-                       if (__area_unmap(mach, ent->hva, ent->gpa, diff) == -1) {
-                               return -1;
-                       }
-                       ent->gpa  += diff;
-                       ent->hva  += diff;
-                       ent->size -= diff;
+       LIST_FOREACH(ent, areas, list) {
+               /* Collision on HVA */
+               if (hva >= ent->hva && hva < ent->hva + ent->size) {
+                       return false;
+               }
+               if (hva + size >= ent->hva &&
+                   hva + size < ent->hva + ent->size) {
+                       return false;
+               }
+               if (hva <= ent->hva && hva + size >= ent->hva + ent->size) {
+                       return false;
                }
 
-               /* Case 2. */
-               if ((gpa >= ent->gpa) && (gpa + size <= ent->gpa + ent->size)) {
-                       /* First half. */
-                       tmp = malloc(sizeof(*tmp));
-                       tmp->gpa = ent->gpa;
-                       tmp->hva = ent->hva;
-                       tmp->size = (gpa - ent->gpa);
-                       LIST_INSERT_BEFORE(ent, tmp, list);
-                       /* Second half. */
-                       ent->gpa  += tmp->size;
-                       ent->hva  += tmp->size;
-                       ent->size -= tmp->size;
-                       diff = size;
-                       if (__area_unmap(mach, ent->hva, ent->gpa, diff) == -1) {
-                               return -1;
-                       }
-                       ent->gpa  += diff;
-                       ent->hva  += diff;
-                       ent->size -= diff;
+               /* Collision on GPA */
+               if (gpa >= ent->gpa && gpa < ent->gpa + ent->size) {
+                       return false;
                }
-
-               /* Case 3. */
-               if ((gpa < ent->gpa + ent->size) &&
-                   (gpa + size > ent->gpa + ent->size)) {
-                       diff = (ent->gpa + ent->size) - gpa;
-                       if (__area_unmap(mach, hva, gpa, diff) == -1) {
-                               return -1;
-                       }
-                       ent->size -= diff;
+               if (gpa + size >= ent->gpa &&
+                   gpa + size < ent->gpa + ent->size) {
+                       return false;
                }
-
-               /* Case 4. */
-               if ((gpa < ent->gpa + ent->size) &&
-                   (gpa + size > ent->gpa + ent->size)) {
-                       if (__area_unmap(mach, ent->hva, ent->gpa, ent->size) == -1) {
-                               return -1;
-                       }
-                       LIST_REMOVE(ent, list);
-                       free(ent);
+               if (gpa <= ent->gpa && gpa + size >= ent->gpa + ent->size) {
+                       return false;
                }
        }
 
-       return 0;
+       return true;
 }
 
 static int
@@ -147,7 +98,11 @@
 {
        area_list_t *areas = mach->areas;
        area_t *area;
-       int ret;
+
+       if (!__area_isvalid(mach, hva, gpa, size)) {
+               errno = EINVAL;
+               return -1;
+       }
 
        area = malloc(sizeof(*area));
        if (area == NULL)
@@ -156,14 +111,27 @@
        area->hva = hva;
        area->size = size;
 
-       ret = __area_dig_hole(mach, hva, gpa, size);
-       if (ret == -1) {
-               free(area);
-               return -1;
+       LIST_INSERT_HEAD(areas, area, list);
+
+       return 0;
+}
+
+static int
+__area_delete(struct nvmm_machine *mach, uintptr_t hva, gpaddr_t gpa,
+    size_t size)
+{
+       area_list_t *areas = mach->areas;
+       area_t *ent, *nxt;
+
+       LIST_FOREACH_SAFE(ent, areas, list, nxt) {
+               if (hva == ent->hva && gpa == ent->gpa && size == ent->size) {
+                       LIST_REMOVE(ent, list);
+                       free(ent);
+                       return 0;
+               }
        }
 
-       LIST_INSERT_HEAD(areas, area, list);
-       return 0;
+       return -1;
 }
 
 static void
@@ -450,11 +418,28 @@
 nvmm_gpa_unmap(struct nvmm_machine *mach, uintptr_t hva, gpaddr_t gpa,
     size_t size)
 {
+       struct nvmm_ioc_gpa_unmap args;
+       int ret;
+
        if (nvmm_init() == -1) {
                return -1;
        }
 
-       return __area_dig_hole(mach, hva, gpa, size);
+       ret = __area_delete(mach, hva, gpa, size);
+       if (ret == -1)
+               return -1;
+
+       args.machid = mach->machid;
+       args.gpa = gpa;
+       args.size = size;
+
+       ret = ioctl(nvmm_fd, NVMM_IOC_GPA_UNMAP, &args);
+       if (ret == -1)
+               return -1;
+
+       ret = munmap((void *)hva, size);
+
+       return ret;
 }
 
 /*