diff options
Diffstat (limited to 'block/qcow2-cache.c')
| -rw-r--r-- | block/qcow2-cache.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/block/qcow2-cache.c b/block/qcow2-cache.c index 53b8afc3d3..f63e7d8e70 100644 --- a/block/qcow2-cache.c +++ b/block/qcow2-cache.c @@ -22,8 +22,16 @@ * THE SOFTWARE. */ +/* Needed for CONFIG_MADVISE */ +#include "config-host.h" + +#if defined(CONFIG_MADVISE) || defined(CONFIG_POSIX_MADVISE) +#include <sys/mman.h> +#endif + #include "block/block_int.h" #include "qemu-common.h" +#include "qemu/osdep.h" #include "qcow2.h" #include "trace.h" @@ -60,6 +68,22 @@ static inline int qcow2_cache_get_table_idx(BlockDriverState *bs, return idx; } +static void qcow2_cache_table_release(BlockDriverState *bs, Qcow2Cache *c, + int i, int num_tables) +{ +#if QEMU_MADV_DONTNEED != QEMU_MADV_INVALID + BDRVQcowState *s = bs->opaque; + void *t = qcow2_cache_get_table_addr(bs, c, i); + int align = getpagesize(); + size_t mem_size = (size_t) s->cluster_size * num_tables; + size_t offset = QEMU_ALIGN_UP((uintptr_t) t, align) - (uintptr_t) t; + size_t length = QEMU_ALIGN_DOWN(mem_size - offset, align); + if (length > 0) { + qemu_madvise((uint8_t *) t + offset, length, QEMU_MADV_DONTNEED); + } +#endif +} + Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables) { BDRVQcowState *s = bs->opaque; @@ -237,6 +261,8 @@ int qcow2_cache_empty(BlockDriverState *bs, Qcow2Cache *c) c->entries[i].lru_counter = 0; } + qcow2_cache_table_release(bs, c, 0, c->size); + c->lru_counter = 0; return 0; |