Re: [PATCH v2] ubifs: ubifs_dump: dump master node

[Dongsheng Yang <yangds.fnst@cn.fujitsu.com>]

On 10/09/2015 12:05 PM, Dongsheng Yang wrote:
> Search the master lebs and found the latest master node.
> Then dump it out.
>
> Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
> ---
> changelog:
> 	- v1:
> 		fix a bug in error path in scan_for_master();
>
>   Makefile                            |   1 +
>   ubifs-utils/ubifs_dump/ubifs_dump.c | 139 +++++++++++++++++++++++++++++-------
>   2 files changed, 113 insertions(+), 27 deletions(-)
>
> diff --git a/Makefile b/Makefile
> index cad71dc..7abbef9 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -133,6 +133,7 @@ $(foreach v,$(UBI_BINS),$(eval $(call mkdep,ubi-utils/,$(v),libubi.a ubiutils-co
>   $(foreach v,crc16.o lpt.o compr.o devtable.o io.o hashtable.o hashtable_itr.o,$(eval UBIFS_LIBS += ../lib/$(v)))
>
>   obj-ubifs_dump = $(UBIFS_LIBS)
> +obj-ubifs_dump += ../lib/scan.o
>   LDFLAGS_ubifs_dump = $(ZLIBLDFLAGS) $(LZOLDFLAGS) $(UUIDLDFLAGS)
>   LDLIBS_ubifs_dump = -lz -llzo2 -lm -luuid
>   $(call mkdep,ubifs-utils/ubifs_dump/,ubifs_dump,,ubi-utils/libubi.a)
> diff --git a/ubifs-utils/ubifs_dump/ubifs_dump.c b/ubifs-utils/ubifs_dump/ubifs_dump.c
> index 9ddb0f7..f7fac0d 100644
> --- a/ubifs-utils/ubifs_dump/ubifs_dump.c
> +++ b/ubifs-utils/ubifs_dump/ubifs_dump.c
> @@ -2,9 +2,11 @@
>   #define PROGRAM_NAME "ubifs-dump"
>   #include "common.h"
>
> +#include "ubifs.h"
>   #include "io.h"
>   #include "key.h"
>   #include "lpt.h"
> +#include "scan.h"
>
>   #define DBG_KEY_BUF_LEN		48
>
> @@ -17,9 +19,6 @@ static const struct option longopts[] = {
>   struct ubifs_info info_;
>   static struct ubifs_info *c = &info_;
>
> -/* Global buffers */
> -static void *leb_buf;
> -
>   /* Global nodes*/
>   struct ubifs_mst_node mst;
>   struct ubifs_sb_node sup;
> @@ -376,26 +375,6 @@ void dump_node(const struct ubifs_info *c, const void *node)
>   	printf("\n");
>   }
>
> -/**
> - * init - initialize things.
> - */
> -static int init(void)
> -{
> -	leb_buf = malloc(c->leb_size);
> -	if (!leb_buf)
> -		return err_msg("out of memory");
> -
> -	return 0;
> -}
> -
> -/**
> - * deinit - deinitialize things.
> - */
> -static void deinit(void)
> -{
> -	free(leb_buf);
> -}
> -
>   /*
>    * init_constants_sb - initialize UBIFS constants.
>    * @c: UBIFS file-system description object
> @@ -498,20 +477,126 @@ static int dump_super(void)
>   	return init_constants_sb(c);
>   }
>
> -static int dump()
> +/**
> + * scan_for_master - search the valid master node.
> + * @c: UBIFS file-system description object
> + *
> + * This function scans the master node LEBs and search for the latest master
> + * node. Returns zero in case of success, %-EUCLEAN if there master area is
> + * corrupted and requires recovery, and a negative error code in case of
> + * failure.
> + */
> +static int scan_for_master(struct ubifs_info *c, struct ubifs_mst_node *mst_node)
>   {
> +	struct ubifs_scan_leb *sleb;
> +	struct ubifs_scan_node *snod;
> +	int lnum, offs = 0, nodes_cnt;
> +	static void *leb_buf;
>   	int err = 0;
>
> -	err = init();
> -	if (err)
> +	lnum = UBIFS_MST_LNUM;
> +
> +	leb_buf = malloc(c->leb_size);
> +	if (!leb_buf)
> +		return -ENOMEM;
> +
> +	sleb = ubifs_scan(c, lnum, 0, leb_buf, 1);
> +	if (IS_ERR(sleb))
> +		return PTR_ERR(sleb);

Damn, forgot to free leb_buf. will send v3 soon.

Yang
> +	nodes_cnt = sleb->nodes_cnt;
> +	if (nodes_cnt > 0) {
> +		snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node,
> +				  list);
> +		if (snod->type != UBIFS_MST_NODE) {
> +			err = -EINVAL;
> +			goto out;
> +		}
> +		memcpy(mst_node, snod->node, snod->len);
> +		offs = snod->offs;
> +	}
> +	ubifs_scan_destroy(sleb);
> +
> +	lnum += 1;
> +
> +	sleb = ubifs_scan(c, lnum, 0, leb_buf, 1);
> +	if (IS_ERR(sleb)) {
> +		return PTR_ERR(sleb);
> +	}
> +	err = -EUCLEAN;
> +	if (sleb->nodes_cnt != nodes_cnt)
> +		goto out;
> +	if (!sleb->nodes_cnt)
> +		goto out;
> +	snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node, list);
> +	if (snod->type != UBIFS_MST_NODE) {
> +		err = -EINVAL;
> +		goto out;
> +	}
> +	if (snod->offs != offs)
>   		goto out;
> +	if (memcmp((void *)mst_node + UBIFS_CH_SZ,
> +		   (void *)snod->node + UBIFS_CH_SZ,
> +		   UBIFS_MST_NODE_SZ - UBIFS_CH_SZ))
> +		goto out;
> +	err = 0;
> +
> +out:
> +	free(leb_buf);
> +	ubifs_scan_destroy(sleb);
> +	return err;
> +}
> +
> +static int dump_master(void)
> +{
> +	int err = 0;
> +
> +	printf("MASTER: \n");
> +	err = scan_for_master(c, &mst);
> +	if (err)
> +		return err;
> +	dump_node(c, &mst);
> +	mst.flags &= cpu_to_le32(~UBIFS_MST_RCVRY);
> +
> +	c->max_sqnum       = le64_to_cpu(mst.ch.sqnum);
> +	c->highest_inum    = le64_to_cpu(mst.highest_inum);
> +	c->zroot.lnum      = le32_to_cpu(mst.root_lnum);
> +	c->zroot.offs      = le32_to_cpu(mst.root_offs);
> +	c->zroot.len       = le32_to_cpu(mst.root_len);
> +	c->gc_lnum         = le32_to_cpu(mst.gc_lnum);
> +	c->ihead_lnum      = le32_to_cpu(mst.ihead_lnum);
> +	c->ihead_offs      = le32_to_cpu(mst.ihead_offs);
> +	c->lpt_lnum        = le32_to_cpu(mst.lpt_lnum);
> +	c->lpt_offs        = le32_to_cpu(mst.lpt_offs);
> +	c->nhead_lnum      = le32_to_cpu(mst.nhead_lnum);
> +	c->nhead_offs      = le32_to_cpu(mst.nhead_offs);
> +	c->ltab_lnum       = le32_to_cpu(mst.ltab_lnum);
> +	c->ltab_offs       = le32_to_cpu(mst.ltab_offs);
> +	c->lsave_lnum      = le32_to_cpu(mst.lsave_lnum);
> +	c->lsave_offs      = le32_to_cpu(mst.lsave_offs);
> +	c->lscan_lnum      = le32_to_cpu(mst.lscan_lnum);
> +	c->lst.empty_lebs  = le32_to_cpu(mst.empty_lebs);
> +	c->lst.idx_lebs    = le32_to_cpu(mst.idx_lebs);
> +	c->lst.total_free  = le64_to_cpu(mst.total_free);
> +	c->lst.total_dirty = le64_to_cpu(mst.total_dirty);
> +	c->lst.total_used  = le64_to_cpu(mst.total_used);
> +	c->lst.total_dead  = le64_to_cpu(mst.total_dead);
> +	c->lst.total_dark  = le64_to_cpu(mst.total_dark);
> +
> +	return 0;
> +}
> +
> +static int dump()
> +{
> +	int err = 0;
>
>   	err = dump_super();
>   	if (err)
>   		goto out;
>
> +	err = dump_master();
> +	if (err)
> +		goto out;
>   out:
> -	deinit();
>   	return err;
>   }
>
>