From a894005f50744485dfd84e73c3db325a8d65ad1d Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Tue, 14 Feb 2012 11:13:44 +0100 Subject: [PATCH 19/99] vmdk: Clean up backing file handling RH-Author: Kevin Wolf Message-id: <1329218101-24213-20-git-send-email-kwolf@redhat.com> Patchwork-id: 37211 O-Subject: [RHEL-6.3 qemu-kvm PATCH v2 19/96] vmdk: Clean up backing file handling Bugzilla: 783950 RH-Acked-by: Paolo Bonzini RH-Acked-by: Marcelo Tosatti RH-Acked-by: Laszlo Ersek Bugzilla: 783950 VMDK is doing interesting things when it needs to open a backing file. This patch changes that part to look more like in other drivers. The nice side effect is that the file name isn't needed any more in the open function. Signed-off-by: Kevin Wolf (cherry picked from commit 9949f97e84c8040fde6116cb438f2999c52f023a) --- block/vmdk.c | 58 +++++++++------------------------------------------------- 1 files changed, 9 insertions(+), 49 deletions(-) Signed-off-by: Michal Novotny --- block/vmdk.c | 58 +++++++++------------------------------------------------- 1 files changed, 9 insertions(+), 49 deletions(-) diff --git a/block/vmdk.c b/block/vmdk.c index 95165ca..a080886 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -76,7 +76,6 @@ typedef struct BDRVVmdkState { unsigned int cluster_sectors; uint32_t parent_cid; - int is_parent; } BDRVVmdkState; typedef struct VmdkMetaData { @@ -338,19 +337,11 @@ fail: return ret; } -static void vmdk_parent_close(BlockDriverState *bs) -{ - if (bs->backing_hd) - bdrv_close(bs->backing_hd); -} - -static int parent_open = 0; -static int vmdk_parent_open(BlockDriverState *bs, const char * filename) +static int vmdk_parent_open(BlockDriverState *bs) { BDRVVmdkState *s = bs->opaque; char *p_name; char desc[DESC_SIZE]; - char parent_img_name[1024]; /* the descriptor offset = 0x200 */ if (bdrv_pread(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE) @@ -358,7 +349,6 @@ static int vmdk_parent_open(BlockDriverState *bs, const char * filename) if ((p_name = strstr(desc,"parentFileNameHint")) != NULL) { char *end_name; - struct stat file_buf; p_name += sizeof("parentFileNameHint") + 1; if ((end_name = strchr(p_name,'\"')) == NULL) @@ -367,24 +357,6 @@ static int vmdk_parent_open(BlockDriverState *bs, const char * filename) return -1; pstrcpy(bs->backing_file, end_name - p_name + 1, p_name); - if (stat(bs->backing_file, &file_buf) != 0) { - path_combine(parent_img_name, sizeof(parent_img_name), - filename, bs->backing_file); - } else { - pstrcpy(parent_img_name, sizeof(parent_img_name), - bs->backing_file); - } - - bs->backing_hd = bdrv_new(""); - if (!bs->backing_hd) { - failure: - bdrv_close(s->hd); - return -1; - } - parent_open = 1; - if (bdrv_open(bs->backing_hd, parent_img_name, 0, NULL) < 0) - goto failure; - parent_open = 0; } return 0; @@ -396,11 +368,6 @@ static int vmdk_open(BlockDriverState *bs, const char *filename, int flags) uint32_t magic; int l1_size, i, ret; - if (parent_open) { - /* Parent must be opened as RO, no RDWR. */ - flags = 0; - } - ret = bdrv_file_open(&s->hd, filename, flags); if (ret < 0) return ret; @@ -436,13 +403,8 @@ static int vmdk_open(BlockDriverState *bs, const char *filename, int flags) s->l1_table_offset = le64_to_cpu(header.rgd_offset) << 9; s->l1_backup_table_offset = le64_to_cpu(header.gd_offset) << 9; - if (parent_open) - s->is_parent = 1; - else - s->is_parent = 0; - // try to open parent images, if exist - if (vmdk_parent_open(bs, filename) != 0) + if (vmdk_parent_open(bs) != 0) goto fail; // write the CID once after the image creation s->parent_cid = vmdk_read_cid(bs,1); @@ -583,15 +545,15 @@ static uint64_t get_cluster_offset(BlockDriverState *bs, VmdkMetaData *m_data, if (!cluster_offset) { if (!allocate) return 0; + // Avoid the L2 tables update for the images that have snapshots. - if (!s->is_parent) { - cluster_offset = bdrv_getlength(s->hd); - bdrv_truncate(s->hd, cluster_offset + (s->cluster_sectors << 9)); + cluster_offset = bdrv_getlength(s->hd); + bdrv_truncate(s->hd, cluster_offset + (s->cluster_sectors << 9)); + + cluster_offset >>= 9; + tmp = cpu_to_le32(cluster_offset); + l2_table[l2_index] = tmp; - cluster_offset >>= 9; - tmp = cpu_to_le32(cluster_offset); - l2_table[l2_index] = tmp; - } /* First of all we write grain itself, to avoid race condition * that may to corrupt the image. * This problem may occur because of insufficient space on host disk @@ -866,8 +828,6 @@ static void vmdk_close(BlockDriverState *bs) qemu_free(s->l1_table); qemu_free(s->l2_cache); - // try to close parent image, if exist - vmdk_parent_close(s->hd); bdrv_delete(s->hd); } -- 1.7.7.5