iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

libnvdimm, btt: consolidate arena validation

Browse Source 
Use arena_is_valid as a common routine for checking the validity of an
info block from both discover_arenas, and nd_btt_probe.

As a result, don't check for validity of the BTT's UUID, and lbasize.
The checksum in the BTT info block guarantees self-consistency, and when
we're called from nd_btt_probe, we don't have a valid uuid or lbasize
available to check against.

Also cleanup to return a bool instead of an int.

Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Vishal Verma 2015-07-29 14:58:08 -06:00 committed by Dan Williams
parent fbde1414ac
commit ab45e76327
3 changed files with 37 additions and 36 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
drivers/nvdimm/btt.c
View File

@ -582,32 +582,6 @@ static void free_arenas(struct btt *btt)
}
}
/*
* This function checks if the metadata layout is valid and error free
*/
static int arena_is_valid(struct nd_btt *nd_btt, struct btt_sb *super)
{
u64 checksum;
if (memcmp(super->uuid, nd_btt->uuid, 16))
return 0;
checksum = le64_to_cpu(super->checksum);
super->checksum = 0;
if (checksum != nd_btt_sb_checksum(super))
return 0;
super->checksum = cpu_to_le64(checksum);
if (nd_btt->lbasize != le32_to_cpu(super->external_lbasize))
return 0;
/* TODO: figure out action for this */
if ((le32_to_cpu(super->flags) & IB_FLAG_ERROR_MASK) != 0)
dev_info(&nd_btt->dev, "Found arena with an error flag\n");
return 1;
}
/*
* This function reads an existing valid btt superblock and
* populates the corresponding arena_info struct
@ -665,7 +639,7 @@ static int discover_arenas(struct btt *btt)
if (ret)
goto out;
if (!arena_is_valid(btt->nd_btt, super)) {
if (!nd_btt_arena_is_valid(btt->nd_btt, super)) {
if (remaining == btt->rawsize) {
btt->init_state = INIT_NOTFOUND;
dev_info(to_dev(arena), "No existing arenas\n");

3
drivers/nvdimm/btt.h
View File

@ -182,4 +182,7 @@ struct btt {
int init_state;
int num_arenas;
};
bool nd_btt_arena_is_valid(struct nd_btt *nd_btt, struct btt_sb *super);
#endif

42
drivers/nvdimm/btt_devs.c
View File

@ -342,6 +342,38 @@ struct device *nd_btt_create(struct nd_region *nd_region)
return dev;
}
/**
* nd_btt_arena_is_valid - check if the metadata layout is valid
* @nd_btt: device with BTT geometry and backing device info
* @super: pointer to the arena's info block being tested
*
* Check consistency of the btt info block with itself by validating
* the checksum.
*
* Returns:
* false for an invalid info block, true for a valid one
*/
bool nd_btt_arena_is_valid(struct nd_btt *nd_btt, struct btt_sb *super)
{
u64 checksum;
if (memcmp(super->signature, BTT_SIG, BTT_SIG_LEN) != 0)
return false;
checksum = le64_to_cpu(super->checksum);
super->checksum = 0;
if (checksum != nd_btt_sb_checksum(super))
return false;
super->checksum = cpu_to_le64(checksum);
/* TODO: figure out action for this */
if ((le32_to_cpu(super->flags) & IB_FLAG_ERROR_MASK) != 0)
dev_info(&nd_btt->dev, "Found arena with an error flag\n");
return true;
}
EXPORT_SYMBOL(nd_btt_arena_is_valid);
/*
* nd_btt_sb_checksum: compute checksum for btt info block
*
@ -364,8 +396,6 @@ EXPORT_SYMBOL(nd_btt_sb_checksum);
static int __nd_btt_probe(struct nd_btt *nd_btt,
struct nd_namespace_common *ndns, struct btt_sb *btt_sb)
{
u64 checksum;
if (!btt_sb || !ndns || !nd_btt)
return -ENODEV;
@ -375,15 +405,9 @@ static int __nd_btt_probe(struct nd_btt *nd_btt,
if (nvdimm_namespace_capacity(ndns) < SZ_16M)
return -ENXIO;
if (memcmp(btt_sb->signature, BTT_SIG, BTT_SIG_LEN) != 0)
if (!nd_btt_arena_is_valid(nd_btt, btt_sb))
return -ENODEV;
checksum = le64_to_cpu(btt_sb->checksum);
btt_sb->checksum = 0;
if (checksum != nd_btt_sb_checksum(btt_sb))
return -ENODEV;
btt_sb->checksum = cpu_to_le64(checksum);
nd_btt->lbasize = le32_to_cpu(btt_sb->external_lbasize);
nd_btt->uuid = kmemdup(btt_sb->uuid, 16, GFP_KERNEL);
if (!nd_btt->uuid)