Until this commit the assumed length of all cache entries has been
exactly one page. To make other sizes possible, the length is now
stored in struct cache_entry. Note that cache_search may return a
pointer in the middle of a cache buffer.
Signed-off-by: Petr Tesarik <ptesarik at suse.cz>
---
cache.c | 12 ++++++++----
cache.h | 3 ++-
makedumpfile.c | 2 +-
3 files changed, 11 insertions(+), 6 deletions(-)
diff --git a/cache.c b/cache.c
index ccd67ca..938eda6 100644
--- a/cache.c
+++ b/cache.c
@@ -79,17 +79,20 @@ remove_entry(struct cache *cache, struct cache_entry *entry)
}
void *
-cache_search(unsigned long long paddr)
+cache_search(unsigned long long paddr, unsigned long length)
{
struct cache_entry *entry;
- for (entry = used.head; entry; entry = entry->next)
- if (entry->paddr == paddr) {
+ for (entry = used.head; entry; entry = entry->next) {
+ size_t off = paddr - entry->paddr;
+ if (off < entry->buflen &&
+ length <= entry->buflen - off) {
if (entry != used.head) {
remove_entry(&used, entry);
add_entry(&used, entry);
}
- return entry->bufptr;
+ return entry->bufptr + off;
}
+ }
return NULL; /* cache miss */
}
@@ -111,6 +114,7 @@ cache_alloc(unsigned long long paddr)
idx = entry - entries;
entry->paddr = paddr;
entry->bufptr = cachebuf + idx * info->page_size;
+ entry->buflen = info->page_size;
add_entry(&pending, entry);
return entry;
diff --git a/cache.h b/cache.h
index 0e65f97..792ba6c 100644
--- a/cache.h
+++ b/cache.h
@@ -22,11 +22,12 @@
struct cache_entry {
unsigned long long paddr;
void *bufptr;
+ unsigned long buflen;
struct cache_entry *next, *prev;
};
int cache_init(void);
-void *cache_search(unsigned long long paddr);
+void *cache_search(unsigned long long paddr, unsigned long length);
struct cache_entry *cache_alloc(unsigned long long paddr);
void cache_add(struct cache_entry *entry);
void cache_free(struct cache_entry *entry);
diff --git a/makedumpfile.c b/makedumpfile.c
index d778139..f1aad08 100644
--- a/makedumpfile.c
+++ b/makedumpfile.c
@@ -647,7 +647,7 @@ next_page:
read_size = MIN(info->page_size - PAGEOFFSET(paddr), size);
pgaddr = PAGEBASE(paddr);
- pgbuf = cache_search(pgaddr);
+ pgbuf = cache_search(pgaddr, read_size);
if (!pgbuf) {
++cache_miss;
cached = cache_alloc(pgaddr);
--
1.8.4.5
