fs/xfs/libxfs/xfs_health.h

Source file repositories/reference/linux-study-clean/fs/xfs/libxfs/xfs_health.h

File Facts

System
Linux kernel
Corpus path
fs/xfs/libxfs/xfs_health.h
Extension
.h
Size
11040 bytes
Lines
298
Domain
Core OS
Bucket
VFS And Filesystem Core
Inferred role
Core OS: implementation source
Status
source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

#ifndef __XFS_HEALTH_H__
#define __XFS_HEALTH_H__

struct xfs_group;

/*
 * In-Core Filesystem Health Assessments
 * =====================================
 *
 * We'd like to be able to summarize the current health status of the
 * filesystem so that the administrator knows when it's necessary to schedule
 * some downtime for repairs.  Until then, we would also like to avoid abrupt
 * shutdowns due to corrupt metadata.
 *
 * The online scrub feature evaluates the health of all filesystem metadata.
 * When scrub detects corruption in a piece of metadata it will set the
 * corresponding sickness flag, and repair will clear it if successful.  If
 * problems remain at unmount time, we can also request manual intervention by
 * logging a notice to run xfs_repair.
 *
 * Each health tracking group uses a pair of fields for reporting.  The
 * "checked" field tell us if a given piece of metadata has ever been examined,
 * and the "sick" field tells us if that piece was found to need repairs.
 * Therefore we can conclude that for a given sick flag value:
 *
 *  - checked && sick   => metadata needs repair
 *  - checked && !sick  => metadata is ok
 *  - !checked && sick  => errors have been observed during normal operation,
 *                         but the metadata has not been checked thoroughly
 *  - !checked && !sick => has not been examined since mount
 *
 * Evidence of health problems can be sorted into three basic categories:
 *
 * a) Primary evidence, which signals that something is defective within the
 *    general grouping of metadata.
 *
 * b) Secondary evidence, which are side effects of primary problem but are
 *    not themselves problems.  These can be forgotten when the primary
 *    health problems are addressed.
 *
 * c) Indirect evidence, which points to something being wrong in another
 *    group, but we had to release resources and this is all that's left of
 *    that state.
 */

struct xfs_mount;
struct xfs_perag;
struct xfs_inode;
struct xfs_fsop_geom;
struct xfs_btree_cur;
struct xfs_da_args;
struct xfs_rtgroup;

/* Observable health issues for metadata spanning the entire filesystem. */
#define XFS_SICK_FS_COUNTERS	(1 << 0)  /* summary counters */
#define XFS_SICK_FS_UQUOTA	(1 << 1)  /* user quota */
#define XFS_SICK_FS_GQUOTA	(1 << 2)  /* group quota */
#define XFS_SICK_FS_PQUOTA	(1 << 3)  /* project quota */
#define XFS_SICK_FS_QUOTACHECK	(1 << 4)  /* quota counts */
#define XFS_SICK_FS_NLINKS	(1 << 5)  /* inode link counts */
#define XFS_SICK_FS_METADIR	(1 << 6)  /* metadata directory tree */
#define XFS_SICK_FS_METAPATH	(1 << 7)  /* metadata directory tree path */

/* Observable health issues for realtime group metadata. */
#define XFS_SICK_RG_SUPER	(1 << 0)  /* rt group superblock */
#define XFS_SICK_RG_BITMAP	(1 << 1)  /* rt group bitmap */
#define XFS_SICK_RG_SUMMARY	(1 << 2)  /* rt groups summary */
#define XFS_SICK_RG_RMAPBT	(1 << 3)  /* reverse mappings */
#define XFS_SICK_RG_REFCNTBT	(1 << 4)  /* reference counts */

/* Observable health issues for AG metadata. */
#define XFS_SICK_AG_SB		(1 << 0)  /* superblock */
#define XFS_SICK_AG_AGF		(1 << 1)  /* AGF header */
#define XFS_SICK_AG_AGFL	(1 << 2)  /* AGFL header */
#define XFS_SICK_AG_AGI		(1 << 3)  /* AGI header */
#define XFS_SICK_AG_BNOBT	(1 << 4)  /* free space by block */
#define XFS_SICK_AG_CNTBT	(1 << 5)  /* free space by length */
#define XFS_SICK_AG_INOBT	(1 << 6)  /* inode index */
#define XFS_SICK_AG_FINOBT	(1 << 7)  /* free inode index */
#define XFS_SICK_AG_RMAPBT	(1 << 8)  /* reverse mappings */
#define XFS_SICK_AG_REFCNTBT	(1 << 9)  /* reference counts */
#define XFS_SICK_AG_INODES	(1 << 10) /* inactivated bad inodes */

/* Observable health issues for inode metadata. */
#define XFS_SICK_INO_CORE	(1 << 0)  /* inode core */
#define XFS_SICK_INO_BMBTD	(1 << 1)  /* data fork */
#define XFS_SICK_INO_BMBTA	(1 << 2)  /* attr fork */
#define XFS_SICK_INO_BMBTC	(1 << 3)  /* cow fork */
#define XFS_SICK_INO_DIR	(1 << 4)  /* directory */
#define XFS_SICK_INO_XATTR	(1 << 5)  /* extended attributes */

Annotation

Implementation Notes