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authorRajithaY <rajithax.yerrumsetty@intel.com>2017-04-25 03:31:15 -0700
committerRajitha Yerrumchetty <rajithax.yerrumsetty@intel.com>2017-05-22 06:48:08 +0000
commitbb756eebdac6fd24e8919e2c43f7d2c8c4091f59 (patch)
treeca11e03542edf2d8f631efeca5e1626d211107e3 /qemu/block/qcow2-cache.c
parenta14b48d18a9ed03ec191cf16b162206998a895ce (diff)
Adding qemu as a submodule of KVMFORNFV
This Patch includes the changes to add qemu as a submodule to kvmfornfv repo and make use of the updated latest qemu for the execution of all testcase Change-Id: I1280af507a857675c7f81d30c95255635667bdd7 Signed-off-by:RajithaY<rajithax.yerrumsetty@intel.com>
Diffstat (limited to 'qemu/block/qcow2-cache.c')
-rw-r--r--qemu/block/qcow2-cache.c411
1 files changed, 0 insertions, 411 deletions
diff --git a/qemu/block/qcow2-cache.c b/qemu/block/qcow2-cache.c
deleted file mode 100644
index 0fe8edae4..000000000
--- a/qemu/block/qcow2-cache.c
+++ /dev/null
@@ -1,411 +0,0 @@
-/*
- * L2/refcount table cache for the QCOW2 format
- *
- * Copyright (c) 2010 Kevin Wolf <kwolf@redhat.com>
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
- * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
- */
-
-/* Needed for CONFIG_MADVISE */
-#include "qemu/osdep.h"
-
-#if defined(CONFIG_MADVISE) || defined(CONFIG_POSIX_MADVISE)
-#include <sys/mman.h>
-#endif
-
-#include "block/block_int.h"
-#include "qemu-common.h"
-#include "qcow2.h"
-#include "trace.h"
-
-typedef struct Qcow2CachedTable {
- int64_t offset;
- uint64_t lru_counter;
- int ref;
- bool dirty;
-} Qcow2CachedTable;
-
-struct Qcow2Cache {
- Qcow2CachedTable *entries;
- struct Qcow2Cache *depends;
- int size;
- bool depends_on_flush;
- void *table_array;
- uint64_t lru_counter;
- uint64_t cache_clean_lru_counter;
-};
-
-static inline void *qcow2_cache_get_table_addr(BlockDriverState *bs,
- Qcow2Cache *c, int table)
-{
- BDRVQcow2State *s = bs->opaque;
- return (uint8_t *) c->table_array + (size_t) table * s->cluster_size;
-}
-
-static inline int qcow2_cache_get_table_idx(BlockDriverState *bs,
- Qcow2Cache *c, void *table)
-{
- BDRVQcow2State *s = bs->opaque;
- ptrdiff_t table_offset = (uint8_t *) table - (uint8_t *) c->table_array;
- int idx = table_offset / s->cluster_size;
- assert(idx >= 0 && idx < c->size && table_offset % s->cluster_size == 0);
- return idx;
-}
-
-static void qcow2_cache_table_release(BlockDriverState *bs, Qcow2Cache *c,
- int i, int num_tables)
-{
-#if QEMU_MADV_DONTNEED != QEMU_MADV_INVALID
- BDRVQcow2State *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
-}
-
-static inline bool can_clean_entry(Qcow2Cache *c, int i)
-{
- Qcow2CachedTable *t = &c->entries[i];
- return t->ref == 0 && !t->dirty && t->offset != 0 &&
- t->lru_counter <= c->cache_clean_lru_counter;
-}
-
-void qcow2_cache_clean_unused(BlockDriverState *bs, Qcow2Cache *c)
-{
- int i = 0;
- while (i < c->size) {
- int to_clean = 0;
-
- /* Skip the entries that we don't need to clean */
- while (i < c->size && !can_clean_entry(c, i)) {
- i++;
- }
-
- /* And count how many we can clean in a row */
- while (i < c->size && can_clean_entry(c, i)) {
- c->entries[i].offset = 0;
- c->entries[i].lru_counter = 0;
- i++;
- to_clean++;
- }
-
- if (to_clean > 0) {
- qcow2_cache_table_release(bs, c, i - to_clean, to_clean);
- }
- }
-
- c->cache_clean_lru_counter = c->lru_counter;
-}
-
-Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables)
-{
- BDRVQcow2State *s = bs->opaque;
- Qcow2Cache *c;
-
- c = g_new0(Qcow2Cache, 1);
- c->size = num_tables;
- c->entries = g_try_new0(Qcow2CachedTable, num_tables);
- c->table_array = qemu_try_blockalign(bs->file->bs,
- (size_t) num_tables * s->cluster_size);
-
- if (!c->entries || !c->table_array) {
- qemu_vfree(c->table_array);
- g_free(c->entries);
- g_free(c);
- c = NULL;
- }
-
- return c;
-}
-
-int qcow2_cache_destroy(BlockDriverState *bs, Qcow2Cache *c)
-{
- int i;
-
- for (i = 0; i < c->size; i++) {
- assert(c->entries[i].ref == 0);
- }
-
- qemu_vfree(c->table_array);
- g_free(c->entries);
- g_free(c);
-
- return 0;
-}
-
-static int qcow2_cache_flush_dependency(BlockDriverState *bs, Qcow2Cache *c)
-{
- int ret;
-
- ret = qcow2_cache_flush(bs, c->depends);
- if (ret < 0) {
- return ret;
- }
-
- c->depends = NULL;
- c->depends_on_flush = false;
-
- return 0;
-}
-
-static int qcow2_cache_entry_flush(BlockDriverState *bs, Qcow2Cache *c, int i)
-{
- BDRVQcow2State *s = bs->opaque;
- int ret = 0;
-
- if (!c->entries[i].dirty || !c->entries[i].offset) {
- return 0;
- }
-
- trace_qcow2_cache_entry_flush(qemu_coroutine_self(),
- c == s->l2_table_cache, i);
-
- if (c->depends) {
- ret = qcow2_cache_flush_dependency(bs, c);
- } else if (c->depends_on_flush) {
- ret = bdrv_flush(bs->file->bs);
- if (ret >= 0) {
- c->depends_on_flush = false;
- }
- }
-
- if (ret < 0) {
- return ret;
- }
-
- if (c == s->refcount_block_cache) {
- ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_REFCOUNT_BLOCK,
- c->entries[i].offset, s->cluster_size);
- } else if (c == s->l2_table_cache) {
- ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_ACTIVE_L2,
- c->entries[i].offset, s->cluster_size);
- } else {
- ret = qcow2_pre_write_overlap_check(bs, 0,
- c->entries[i].offset, s->cluster_size);
- }
-
- if (ret < 0) {
- return ret;
- }
-
- if (c == s->refcount_block_cache) {
- BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_UPDATE_PART);
- } else if (c == s->l2_table_cache) {
- BLKDBG_EVENT(bs->file, BLKDBG_L2_UPDATE);
- }
-
- ret = bdrv_pwrite(bs->file->bs, c->entries[i].offset,
- qcow2_cache_get_table_addr(bs, c, i), s->cluster_size);
- if (ret < 0) {
- return ret;
- }
-
- c->entries[i].dirty = false;
-
- return 0;
-}
-
-int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c)
-{
- BDRVQcow2State *s = bs->opaque;
- int result = 0;
- int ret;
- int i;
-
- trace_qcow2_cache_flush(qemu_coroutine_self(), c == s->l2_table_cache);
-
- for (i = 0; i < c->size; i++) {
- ret = qcow2_cache_entry_flush(bs, c, i);
- if (ret < 0 && result != -ENOSPC) {
- result = ret;
- }
- }
-
- if (result == 0) {
- ret = bdrv_flush(bs->file->bs);
- if (ret < 0) {
- result = ret;
- }
- }
-
- return result;
-}
-
-int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c,
- Qcow2Cache *dependency)
-{
- int ret;
-
- if (dependency->depends) {
- ret = qcow2_cache_flush_dependency(bs, dependency);
- if (ret < 0) {
- return ret;
- }
- }
-
- if (c->depends && (c->depends != dependency)) {
- ret = qcow2_cache_flush_dependency(bs, c);
- if (ret < 0) {
- return ret;
- }
- }
-
- c->depends = dependency;
- return 0;
-}
-
-void qcow2_cache_depends_on_flush(Qcow2Cache *c)
-{
- c->depends_on_flush = true;
-}
-
-int qcow2_cache_empty(BlockDriverState *bs, Qcow2Cache *c)
-{
- int ret, i;
-
- ret = qcow2_cache_flush(bs, c);
- if (ret < 0) {
- return ret;
- }
-
- for (i = 0; i < c->size; i++) {
- assert(c->entries[i].ref == 0);
- c->entries[i].offset = 0;
- c->entries[i].lru_counter = 0;
- }
-
- qcow2_cache_table_release(bs, c, 0, c->size);
-
- c->lru_counter = 0;
-
- return 0;
-}
-
-static int qcow2_cache_do_get(BlockDriverState *bs, Qcow2Cache *c,
- uint64_t offset, void **table, bool read_from_disk)
-{
- BDRVQcow2State *s = bs->opaque;
- int i;
- int ret;
- int lookup_index;
- uint64_t min_lru_counter = UINT64_MAX;
- int min_lru_index = -1;
-
- trace_qcow2_cache_get(qemu_coroutine_self(), c == s->l2_table_cache,
- offset, read_from_disk);
-
- /* Check if the table is already cached */
- i = lookup_index = (offset / s->cluster_size * 4) % c->size;
- do {
- const Qcow2CachedTable *t = &c->entries[i];
- if (t->offset == offset) {
- goto found;
- }
- if (t->ref == 0 && t->lru_counter < min_lru_counter) {
- min_lru_counter = t->lru_counter;
- min_lru_index = i;
- }
- if (++i == c->size) {
- i = 0;
- }
- } while (i != lookup_index);
-
- if (min_lru_index == -1) {
- /* This can't happen in current synchronous code, but leave the check
- * here as a reminder for whoever starts using AIO with the cache */
- abort();
- }
-
- /* Cache miss: write a table back and replace it */
- i = min_lru_index;
- trace_qcow2_cache_get_replace_entry(qemu_coroutine_self(),
- c == s->l2_table_cache, i);
-
- ret = qcow2_cache_entry_flush(bs, c, i);
- if (ret < 0) {
- return ret;
- }
-
- trace_qcow2_cache_get_read(qemu_coroutine_self(),
- c == s->l2_table_cache, i);
- c->entries[i].offset = 0;
- if (read_from_disk) {
- if (c == s->l2_table_cache) {
- BLKDBG_EVENT(bs->file, BLKDBG_L2_LOAD);
- }
-
- ret = bdrv_pread(bs->file->bs, offset,
- qcow2_cache_get_table_addr(bs, c, i),
- s->cluster_size);
- if (ret < 0) {
- return ret;
- }
- }
-
- c->entries[i].offset = offset;
-
- /* And return the right table */
-found:
- c->entries[i].ref++;
- *table = qcow2_cache_get_table_addr(bs, c, i);
-
- trace_qcow2_cache_get_done(qemu_coroutine_self(),
- c == s->l2_table_cache, i);
-
- return 0;
-}
-
-int qcow2_cache_get(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
- void **table)
-{
- return qcow2_cache_do_get(bs, c, offset, table, true);
-}
-
-int qcow2_cache_get_empty(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
- void **table)
-{
- return qcow2_cache_do_get(bs, c, offset, table, false);
-}
-
-void qcow2_cache_put(BlockDriverState *bs, Qcow2Cache *c, void **table)
-{
- int i = qcow2_cache_get_table_idx(bs, c, *table);
-
- c->entries[i].ref--;
- *table = NULL;
-
- if (c->entries[i].ref == 0) {
- c->entries[i].lru_counter = ++c->lru_counter;
- }
-
- assert(c->entries[i].ref >= 0);
-}
-
-void qcow2_cache_entry_mark_dirty(BlockDriverState *bs, Qcow2Cache *c,
- void *table)
-{
- int i = qcow2_cache_get_table_idx(bs, c, table);
- assert(c->entries[i].offset != 0);
- c->entries[i].dirty = true;
-}