From 1e81dba7a7429775f8d82480acfe9e8b191e3b98 Mon Sep 17 00:00:00 2001 From: Laszlo Ersek Date: Sat, 22 Mar 2014 03:31:07 +0100 Subject: [PATCH 16/30] dump: add APIs to operate DataCache RH-Author: Laszlo Ersek Message-id: <1395459071-19118-16-git-send-email-lersek@redhat.com> Patchwork-id: 58226 O-Subject: [RHEL-6.6 qemu-kvm PATCH 15/19] dump: add APIs to operate DataCache Bugzilla: 1035162 RH-Acked-by: Paolo Bonzini RH-Acked-by: Dr. David Alan Gilbert (git) RH-Acked-by: Luiz Capitulino From: qiaonuohan DataCache is used to store data temporarily, then the data will be written to vmcore. These functions will be called later when writing data of page to vmcore. Signed-off-by: Qiao Nuohan Reviewed-by: Laszlo Ersek Signed-off-by: Luiz Capitulino (cherry picked from commit 64cfba6a47411092c941c8d17256fb5673cc8cbf) Conflicts: dump.h RHEL-6 note: DataCache.offset is of type "off_t"; I'm including in dump.h as a downstream mesure against In file included from cpu-all.h:25, from target-i386/cpu.h:1003, from target-i386/exec.h:66, from cpu-exec.c:20: dump.h:151: error: expected specifier-qualifier-list before 'off_t' Signed-off-by: Laszlo Ersek --- dump.h | 11 +++++++++++ dump.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 58 insertions(+) Signed-off-by: Miroslav Rezanina --- dump.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++ dump.h | 11 +++++++++++ 2 files changed, 58 insertions(+), 0 deletions(-) diff --git a/dump.c b/dump.c index f168264..ce7b430 100644 --- a/dump.c +++ b/dump.c @@ -1165,6 +1165,53 @@ out: return ret; } +static void prepare_data_cache(DataCache *data_cache, DumpState *s, + off_t offset) +{ + data_cache->fd = s->fd; + data_cache->data_size = 0; + data_cache->buf_size = BUFSIZE_DATA_CACHE; + data_cache->buf = g_malloc0(BUFSIZE_DATA_CACHE); + data_cache->offset = offset; +} + +static int write_cache(DataCache *dc, const void *buf, size_t size, + bool flag_sync) +{ + /* + * dc->buf_size should not be less than size, otherwise dc will never be + * enough + */ + assert(size <= dc->buf_size); + + /* + * if flag_sync is set, synchronize data in dc->buf into vmcore. + * otherwise check if the space is enough for caching data in buf, if not, + * write the data in dc->buf to dc->fd and reset dc->buf + */ + if ((!flag_sync && dc->data_size + size > dc->buf_size) || + (flag_sync && dc->data_size > 0)) { + if (write_buffer(dc->fd, dc->offset, dc->buf, dc->data_size) < 0) { + return -1; + } + + dc->offset += dc->data_size; + dc->data_size = 0; + } + + if (!flag_sync) { + memcpy(dc->buf + dc->data_size, buf, size); + dc->data_size += size; + } + + return 0; +} + +static void free_data_cache(DataCache *data_cache) +{ + g_free(data_cache->buf); +} + static ram_addr_t get_start_block(DumpState *s) { GuestPhysBlock *block; diff --git a/dump.h b/dump.h index cbba74a..05d8000 100644 --- a/dump.h +++ b/dump.h @@ -14,6 +14,8 @@ #ifndef DUMP_H #define DUMP_H +#include + #define MAKEDUMPFILE_SIGNATURE "makedumpfile" #define MAX_SIZE_MDF_HEADER (4096) /* max size of makedumpfile_header */ #define TYPE_FLAT_HEADER (1) /* type of flattened format */ @@ -41,6 +43,7 @@ #define DISKDUMP_HEADER_BLOCKS (1) #define BUFSIZE_BITMAP (TARGET_PAGE_SIZE) #define PFN_BUFBITMAP (CHAR_BIT * BUFSIZE_BITMAP) +#define BUFSIZE_DATA_CACHE (TARGET_PAGE_SIZE * 4) typedef struct ArchDumpInfo { int d_machine; /* Architecture */ @@ -142,4 +145,12 @@ typedef struct QEMU_PACKED KdumpSubHeader64 { uint64_t max_mapnr_64; /* header_version 6 and later */ } KdumpSubHeader64; +typedef struct DataCache { + int fd; /* fd of the file where to write the cached data */ + uint8_t *buf; /* buffer for cached data */ + size_t buf_size; /* size of the buf */ + size_t data_size; /* size of cached data in buf */ + off_t offset; /* offset of the file */ +} DataCache; + #endif -- 1.7.1