linux/fs/xfs/libxfs/xfs_dir2.h
Darrick J. Wong 744e6c8ada xfs: constify xfs_name_dotdot
The symbol xfs_name_dotdot is a global variable that the xfs codebase
uses here and there to look up directory dotdot entries.  Currently it's
a non-const variable, which means that it's a mutable global variable.
So far nobody's abused this to cause problems, but let's use the
compiler to enforce that.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2022-03-14 10:23:17 -07:00

252 lines
7.4 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*/
#ifndef __XFS_DIR2_H__
#define __XFS_DIR2_H__
#include "xfs_da_format.h"
#include "xfs_da_btree.h"
struct xfs_da_args;
struct xfs_inode;
struct xfs_mount;
struct xfs_trans;
struct xfs_dir2_sf_hdr;
struct xfs_dir2_sf_entry;
struct xfs_dir2_data_hdr;
struct xfs_dir2_data_entry;
struct xfs_dir2_data_unused;
struct xfs_dir3_icfree_hdr;
struct xfs_dir3_icleaf_hdr;
extern const struct xfs_name xfs_name_dotdot;
/*
* Convert inode mode to directory entry filetype
*/
extern unsigned char xfs_mode_to_ftype(int mode);
/*
* Generic directory interface routines
*/
extern void xfs_dir_startup(void);
extern int xfs_da_mount(struct xfs_mount *mp);
extern void xfs_da_unmount(struct xfs_mount *mp);
extern int xfs_dir_isempty(struct xfs_inode *dp);
extern int xfs_dir_init(struct xfs_trans *tp, struct xfs_inode *dp,
struct xfs_inode *pdp);
extern int xfs_dir_createname(struct xfs_trans *tp, struct xfs_inode *dp,
const struct xfs_name *name, xfs_ino_t inum,
xfs_extlen_t tot);
extern int xfs_dir_lookup(struct xfs_trans *tp, struct xfs_inode *dp,
const struct xfs_name *name, xfs_ino_t *inum,
struct xfs_name *ci_name);
extern int xfs_dir_removename(struct xfs_trans *tp, struct xfs_inode *dp,
struct xfs_name *name, xfs_ino_t ino,
xfs_extlen_t tot);
extern int xfs_dir_replace(struct xfs_trans *tp, struct xfs_inode *dp,
const struct xfs_name *name, xfs_ino_t inum,
xfs_extlen_t tot);
extern int xfs_dir_canenter(struct xfs_trans *tp, struct xfs_inode *dp,
struct xfs_name *name);
/*
* Direct call from the bmap code, bypassing the generic directory layer.
*/
extern int xfs_dir2_sf_to_block(struct xfs_da_args *args);
/*
* Interface routines used by userspace utilities
*/
extern int xfs_dir2_isblock(struct xfs_da_args *args, int *r);
extern int xfs_dir2_isleaf(struct xfs_da_args *args, int *r);
extern int xfs_dir2_shrink_inode(struct xfs_da_args *args, xfs_dir2_db_t db,
struct xfs_buf *bp);
extern void xfs_dir2_data_freescan(struct xfs_mount *mp,
struct xfs_dir2_data_hdr *hdr, int *loghead);
extern void xfs_dir2_data_log_entry(struct xfs_da_args *args,
struct xfs_buf *bp, struct xfs_dir2_data_entry *dep);
extern void xfs_dir2_data_log_header(struct xfs_da_args *args,
struct xfs_buf *bp);
extern void xfs_dir2_data_log_unused(struct xfs_da_args *args,
struct xfs_buf *bp, struct xfs_dir2_data_unused *dup);
extern void xfs_dir2_data_make_free(struct xfs_da_args *args,
struct xfs_buf *bp, xfs_dir2_data_aoff_t offset,
xfs_dir2_data_aoff_t len, int *needlogp, int *needscanp);
extern int xfs_dir2_data_use_free(struct xfs_da_args *args,
struct xfs_buf *bp, struct xfs_dir2_data_unused *dup,
xfs_dir2_data_aoff_t offset, xfs_dir2_data_aoff_t len,
int *needlogp, int *needscanp);
extern struct xfs_dir2_data_free *xfs_dir2_data_freefind(
struct xfs_dir2_data_hdr *hdr, struct xfs_dir2_data_free *bf,
struct xfs_dir2_data_unused *dup);
extern int xfs_dir_ino_validate(struct xfs_mount *mp, xfs_ino_t ino);
extern const struct xfs_buf_ops xfs_dir3_block_buf_ops;
extern const struct xfs_buf_ops xfs_dir3_leafn_buf_ops;
extern const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops;
extern const struct xfs_buf_ops xfs_dir3_free_buf_ops;
extern const struct xfs_buf_ops xfs_dir3_data_buf_ops;
/*
* Directory offset/block conversion functions.
*
* DB blocks here are logical directory block numbers, not filesystem blocks.
*/
/*
* Convert dataptr to byte in file space
*/
static inline xfs_dir2_off_t
xfs_dir2_dataptr_to_byte(xfs_dir2_dataptr_t dp)
{
return (xfs_dir2_off_t)dp << XFS_DIR2_DATA_ALIGN_LOG;
}
/*
* Convert byte in file space to dataptr. It had better be aligned.
*/
static inline xfs_dir2_dataptr_t
xfs_dir2_byte_to_dataptr(xfs_dir2_off_t by)
{
return (xfs_dir2_dataptr_t)(by >> XFS_DIR2_DATA_ALIGN_LOG);
}
/*
* Convert byte in space to (DB) block
*/
static inline xfs_dir2_db_t
xfs_dir2_byte_to_db(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
{
return (xfs_dir2_db_t)(by >> geo->blklog);
}
/*
* Convert dataptr to a block number
*/
static inline xfs_dir2_db_t
xfs_dir2_dataptr_to_db(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
{
return xfs_dir2_byte_to_db(geo, xfs_dir2_dataptr_to_byte(dp));
}
/*
* Convert byte in space to offset in a block
*/
static inline xfs_dir2_data_aoff_t
xfs_dir2_byte_to_off(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
{
return (xfs_dir2_data_aoff_t)(by & (geo->blksize - 1));
}
/*
* Convert dataptr to a byte offset in a block
*/
static inline xfs_dir2_data_aoff_t
xfs_dir2_dataptr_to_off(struct xfs_da_geometry *geo, xfs_dir2_dataptr_t dp)
{
return xfs_dir2_byte_to_off(geo, xfs_dir2_dataptr_to_byte(dp));
}
/*
* Convert block and offset to byte in space
*/
static inline xfs_dir2_off_t
xfs_dir2_db_off_to_byte(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
xfs_dir2_data_aoff_t o)
{
return ((xfs_dir2_off_t)db << geo->blklog) + o;
}
/*
* Convert block (DB) to block (dablk)
*/
static inline xfs_dablk_t
xfs_dir2_db_to_da(struct xfs_da_geometry *geo, xfs_dir2_db_t db)
{
return (xfs_dablk_t)(db << (geo->blklog - geo->fsblog));
}
/*
* Convert byte in space to (DA) block
*/
static inline xfs_dablk_t
xfs_dir2_byte_to_da(struct xfs_da_geometry *geo, xfs_dir2_off_t by)
{
return xfs_dir2_db_to_da(geo, xfs_dir2_byte_to_db(geo, by));
}
/*
* Convert block and offset to dataptr
*/
static inline xfs_dir2_dataptr_t
xfs_dir2_db_off_to_dataptr(struct xfs_da_geometry *geo, xfs_dir2_db_t db,
xfs_dir2_data_aoff_t o)
{
return xfs_dir2_byte_to_dataptr(xfs_dir2_db_off_to_byte(geo, db, o));
}
/*
* Convert block (dablk) to block (DB)
*/
static inline xfs_dir2_db_t
xfs_dir2_da_to_db(struct xfs_da_geometry *geo, xfs_dablk_t da)
{
return (xfs_dir2_db_t)(da >> (geo->blklog - geo->fsblog));
}
/*
* Convert block (dablk) to byte offset in space
*/
static inline xfs_dir2_off_t
xfs_dir2_da_to_byte(struct xfs_da_geometry *geo, xfs_dablk_t da)
{
return xfs_dir2_db_off_to_byte(geo, xfs_dir2_da_to_db(geo, da), 0);
}
/*
* Directory tail pointer accessor functions. Based on block geometry.
*/
static inline struct xfs_dir2_block_tail *
xfs_dir2_block_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_data_hdr *hdr)
{
return ((struct xfs_dir2_block_tail *)
((char *)hdr + geo->blksize)) - 1;
}
static inline struct xfs_dir2_leaf_tail *
xfs_dir2_leaf_tail_p(struct xfs_da_geometry *geo, struct xfs_dir2_leaf *lp)
{
return (struct xfs_dir2_leaf_tail *)
((char *)lp + geo->blksize -
sizeof(struct xfs_dir2_leaf_tail));
}
/*
* The Linux API doesn't pass down the total size of the buffer
* we read into down to the filesystem. With the filldir concept
* it's not needed for correct information, but the XFS dir2 leaf
* code wants an estimate of the buffer size to calculate it's
* readahead window and size the buffers used for mapping to
* physical blocks.
*
* Try to give it an estimate that's good enough, maybe at some
* point we can change the ->readdir prototype to include the
* buffer size. For now we use the current glibc buffer size.
* musl libc hardcodes 2k and dietlibc uses PAGE_SIZE.
*/
#define XFS_READDIR_BUFSIZE (32768)
unsigned char xfs_dir3_get_dtype(struct xfs_mount *mp, uint8_t filetype);
unsigned int xfs_dir3_data_end_offset(struct xfs_da_geometry *geo,
struct xfs_dir2_data_hdr *hdr);
bool xfs_dir2_namecheck(const void *name, size_t length);
#endif /* __XFS_DIR2_H__ */