shaba/lvm2
1
0
Fork 0
mirror of git://sourceware.org/git/lvm2.git synced 2024-12-21 13:34:40 +03:00
Code Releases Activity

dev-type: refine dev_get_primary_dev return codes and add more comments

Browse Source
This commit is contained in:
Peter Rajnoha 2013-06-12 14:33:28 +02:00
parent 56ee1de7e4
commit ebf0898d69
3 changed files with 26 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
lib/device/dev-md.c
View File

@ -141,7 +141,7 @@ static int _md_sysfs_attribute_snprintf(char *path, size_t size,
if (MAJOR(dev) == dt->blkext_major) { if (MAJOR(dev) == dt->blkext_major) {
/* lookup parent MD device from blkext partition */ /* lookup parent MD device from blkext partition */
if (dev_get_primary_dev(dt, blkdev, &dev) < 1) if (!dev_get_primary_dev(dt, blkdev, &dev))
return ret; return ret;
} }

30
lib/device/dev-type.c
View File

@ -203,7 +203,7 @@ int dev_subsystem_part_major(struct dev_types *dt, struct device *dev)
return 1; return 1;
if ((MAJOR(dev->dev) == dt->blkext_major) && if ((MAJOR(dev->dev) == dt->blkext_major) &&
(dev_get_primary_dev(dt, dev, &primary_dev) > 0) && dev_get_primary_dev(dt, dev, &primary_dev) &&
(MAJOR(primary_dev) == dt->md_major)) (MAJOR(primary_dev) == dt->md_major))
return 1; return 1;
@ -320,10 +320,24 @@ int dev_is_partitioned(struct dev_types *dt, struct device *dev)
/* /*
* Get primary dev for the dev supplied. * Get primary dev for the dev supplied.
*
* We can get a primary device for a partition either by:
* A: knowing the number of partitions allowed for the dev and also
* which major:minor number represents the primary and partition device
* (by using the dev_types->dev_type_array)
* B: by the existence of the 'partition' sysfs attribute
* (/dev/block/<major>:<minor>/partition)
*
* Method A is tried first, then method B as a fallback if A fails.
*
* N.B. Method B can only do the decision based on the pure existence of
* the 'partition' sysfs item. There's no direct scan for partition
* tables whatsoever!
*
* Returns: * Returns:
* 0 if the dev is already a primary dev * 0 on error
* 1 if the dev is a partition, primary dev in result * 1 if the dev is already a primary dev, primary dev in 'result'
* -1 on error * 2 if the dev is a partition, primary dev in 'result'
*/ */
int dev_get_primary_dev(struct dev_types *dt, struct device *dev, dev_t *result) int dev_get_primary_dev(struct dev_types *dt, struct device *dev, dev_t *result)
{ {
@ -344,10 +358,10 @@ int dev_get_primary_dev(struct dev_types *dt, struct device *dev, dev_t *result)
if ((parts = dt->dev_type_array[major].max_partitions) > 1) { if ((parts = dt->dev_type_array[major].max_partitions) > 1) {
if ((residue = minor % parts)) { if ((residue = minor % parts)) {
*result = MKDEV((dev_t)major, (minor - residue)); *result = MKDEV((dev_t)major, (minor - residue));
ret = 1; ret = 2;
} else { } else {
*result = dev->dev; *result = dev->dev;
ret = 0; /* dev is not a partition! */ ret = 1; /* dev is not a partition! */
} }
goto out; goto out;
} }
@ -370,7 +384,7 @@ int dev_get_primary_dev(struct dev_types *dt, struct device *dev, dev_t *result)
if (errno != ENOENT) if (errno != ENOENT)
log_sys_error("stat", path); log_sys_error("stat", path);
*result = dev->dev; *result = dev->dev;
ret = 0; goto out; /* dev is not a partition! */ ret = 1; goto out; /* dev is not a partition! */
} }
@ -465,7 +479,7 @@ static unsigned long _dev_topology_attribute(struct dev_types *dt,
log_sys_error("stat", path); log_sys_error("stat", path);
return 0; return 0;
} }
if (dev_get_primary_dev(dt, dev, &primary) < 0) if (!dev_get_primary_dev(dt, dev, &primary))
return 0; return 0;
/* get attribute from partition's primary device */ /* get attribute from partition's primary device */

6
lib/filters/filter-mpath.c
View File

@ -130,14 +130,14 @@ static int dev_is_mpath(struct dev_filter *f, struct device *dev)
return 0; return 0;
switch (dev_get_primary_dev(dt, dev, &primary_dev)) { switch (dev_get_primary_dev(dt, dev, &primary_dev)) {
case -1: case 0:
/* Error. */ /* Error. */
log_error("Failed to get primary device for %d:%d.", major, minor); log_error("Failed to get primary device for %d:%d.", major, minor);
return 0; return 0;
case 0: case 1:
/* The dev is already a primary dev. Just continue with the dev. */ /* The dev is already a primary dev. Just continue with the dev. */
break; break;
case 1: case 2:
/* The dev is partition. */ /* The dev is partition. */
name = dev_name(dev); /* name of original dev for log_debug msg */ name = dev_name(dev); /* name of original dev for log_debug msg */