fs/xfs/libxfs/xfs_ialloc.c

Source file repositories/reference/linux-study-clean/fs/xfs/libxfs/xfs_ialloc.c

File Facts

System
Linux kernel
Corpus path
fs/xfs/libxfs/xfs_ialloc.c
Extension
.c
Size
85650 bytes
Lines
3186
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

struct xfs_ialloc_count_inodes {
	xfs_agino_t			count;
	xfs_agino_t			freecount;
};

/* Record inode counts across all inobt records. */
STATIC int
xfs_ialloc_count_inodes_rec(
	struct xfs_btree_cur		*cur,
	const union xfs_btree_rec	*rec,
	void				*priv)
{
	struct xfs_inobt_rec_incore	irec;
	struct xfs_ialloc_count_inodes	*ci = priv;
	xfs_failaddr_t			fa;

	xfs_inobt_btrec_to_irec(cur->bc_mp, rec, &irec);
	fa = xfs_inobt_check_irec(to_perag(cur->bc_group), &irec);
	if (fa)
		return xfs_inobt_complain_bad_rec(cur, fa, &irec);

	ci->count += irec.ir_count;
	ci->freecount += irec.ir_freecount;

	return 0;
}

/* Count allocated and free inodes under an inobt. */
int
xfs_ialloc_count_inodes(
	struct xfs_btree_cur		*cur,
	xfs_agino_t			*count,
	xfs_agino_t			*freecount)
{
	struct xfs_ialloc_count_inodes	ci = {0};
	int				error;

	ASSERT(xfs_btree_is_ino(cur->bc_ops));
	error = xfs_btree_query_all(cur, xfs_ialloc_count_inodes_rec, &ci);
	if (error)
		return error;

	*count = ci.count;
	*freecount = ci.freecount;
	return 0;
}

/*
 * Initialize inode-related geometry information.
 *
 * Compute the inode btree min and max levels and set maxicount.
 *
 * Set the inode cluster size.  This may still be overridden by the file
 * system block size if it is larger than the chosen cluster size.
 *
 * For v5 filesystems, scale the cluster size with the inode size to keep a
 * constant ratio of inode per cluster buffer, but only if mkfs has set the
 * inode alignment value appropriately for larger cluster sizes.
 *
 * Then compute the inode cluster alignment information.
 */
void
xfs_ialloc_setup_geometry(
	struct xfs_mount	*mp)
{
	struct xfs_sb		*sbp = &mp->m_sb;
	struct xfs_ino_geometry	*igeo = M_IGEO(mp);
	uint64_t		icount;
	uint			inodes;

	igeo->new_diflags2 = 0;
	if (xfs_has_bigtime(mp))
		igeo->new_diflags2 |= XFS_DIFLAG2_BIGTIME;
	if (xfs_has_large_extent_counts(mp))
		igeo->new_diflags2 |= XFS_DIFLAG2_NREXT64;

	/* Compute inode btree geometry. */
	igeo->agino_log = sbp->sb_inopblog + sbp->sb_agblklog;
	igeo->inobt_mxr[0] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, true);
	igeo->inobt_mxr[1] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, false);
	igeo->inobt_mnr[0] = igeo->inobt_mxr[0] / 2;
	igeo->inobt_mnr[1] = igeo->inobt_mxr[1] / 2;

	igeo->ialloc_inos = max_t(uint16_t, XFS_INODES_PER_CHUNK,
			sbp->sb_inopblock);
	igeo->ialloc_blks = igeo->ialloc_inos >> sbp->sb_inopblog;

	if (sbp->sb_spino_align)
		igeo->ialloc_min_blks = sbp->sb_spino_align;
	else

Annotation

Implementation Notes