From bb55fde4d8ca587e2ef52ce58a0c22e4d66a08dc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= <marcandre.lureau@redhat.com>
Date: Thu, 25 Aug 2022 12:40:12 +0400
Subject: [PATCH 30/42] dump: simplify a bit kdump get_next_page()
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RH-Author: Cédric Le Goater <clg@redhat.com>
RH-MergeRequest: 226: s390: Enhanced Interpretation for PCI Functions and Secure Execution guest dump
RH-Bugzilla: 1664378 2043909
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Cornelia Huck <cohuck@redhat.com>
RH-Acked-by: Jon Maloy <jmaloy@redhat.com>
RH-Commit: [30/41] 417ac19fa96036e0242f40121ac6e87a9f3f70ba

This should be functionally equivalent, but slightly easier to read,
with simplified paths and checks at the end of the function.

The following patch is a major rewrite to get rid of the assert().

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
(cherry picked from commit 08df343874fcddd260021a04ce3c5a34f2c48164)
Signed-off-by: Cédric Le Goater <clg@redhat.com>
---
 dump/dump.c | 21 ++++++++-------------
 1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/dump/dump.c b/dump/dump.c
index c2c1341ad7..1c49232390 100644
--- a/dump/dump.c
+++ b/dump/dump.c
@@ -1133,17 +1133,11 @@ static bool get_next_page(GuestPhysBlock **blockptr, uint64_t *pfnptr,
     if (!block) {
         block = QTAILQ_FIRST(&s->guest_phys_blocks.head);
         *blockptr = block;
-        assert((block->target_start & ~target_page_mask) == 0);
-        assert((block->target_end & ~target_page_mask) == 0);
-        *pfnptr = dump_paddr_to_pfn(s, block->target_start);
-        if (bufptr) {
-            *bufptr = block->host_addr;
-        }
-        return true;
+        addr = block->target_start;
+    } else {
+        addr = dump_pfn_to_paddr(s, *pfnptr + 1);
     }
-
-    *pfnptr = *pfnptr + 1;
-    addr = dump_pfn_to_paddr(s, *pfnptr);
+    assert(block != NULL);
 
     if ((addr >= block->target_start) &&
         (addr + s->dump_info.page_size <= block->target_end)) {
@@ -1155,12 +1149,13 @@ static bool get_next_page(GuestPhysBlock **blockptr, uint64_t *pfnptr,
         if (!block) {
             return false;
         }
-        assert((block->target_start & ~target_page_mask) == 0);
-        assert((block->target_end & ~target_page_mask) == 0);
-        *pfnptr = dump_paddr_to_pfn(s, block->target_start);
+        addr = block->target_start;
         buf = block->host_addr;
     }
 
+    assert((block->target_start & ~target_page_mask) == 0);
+    assert((block->target_end & ~target_page_mask) == 0);
+    *pfnptr = dump_paddr_to_pfn(s, addr);
     if (bufptr) {
         *bufptr = buf;
     }
-- 
2.37.3