fs/xfs/libxfs/xfs_dir2.h - linux - Git at Google

 /* 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, bool *isblock);
 extern int xfs_dir2_isleaf(struct xfs_da_args *args, bool *isleaf);
 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);

 /*
  * The "ascii-ci" feature was created to speed up case-insensitive lookups for
  * a Samba product.  Because of the inherent problems with CI and UTF-8
  * encoding, etc, it was decided that Samba would be configured to export
  * latin1/iso 8859-1 encodings as that covered >90% of the target markets for
  * the product.  Hence the "ascii-ci" casefolding code could be encoded into
  * the XFS directory operations and remove all the overhead of casefolding from
  * Samba.
  *
  * To provide consistent hashing behavior between the userspace and kernel,
  * these functions prepare names for hashing by transforming specific bytes
  * to other bytes.  Robustness with other encodings is not guaranteed.
  */
 static inline bool xfs_ascii_ci_need_xfrm(unsigned char c)
 {
 	if (c >= 0x41 && c <= 0x5a)	/* A-Z */
 		return true;
 	if (c >= 0xc0 && c <= 0xd6)	/* latin A-O with accents */
 		return true;
 	if (c >= 0xd8 && c <= 0xde)	/* latin O-Y with accents */
 		return true;
 	return false;
 }

 static inline unsigned char xfs_ascii_ci_xfrm(unsigned char c)
 {
 	if (xfs_ascii_ci_need_xfrm(c))
 		c -= 'A' - 'a';
 	return c;
 }

 #endif	/* __XFS_DIR2_H__ */
	/* 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, bool isblock);
	extern int xfs_dir2_isleaf(struct xfs_da_args args, bool isleaf);
	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);

	/*
	* The "ascii-ci" feature was created to speed up case-insensitive lookups for
	* a Samba product. Because of the inherent problems with CI and UTF-8
	* encoding, etc, it was decided that Samba would be configured to export
	* latin1/iso 8859-1 encodings as that covered >90% of the target markets for
	* the product. Hence the "ascii-ci" casefolding code could be encoded into
	* the XFS directory operations and remove all the overhead of casefolding from
	* Samba.
	*
	* To provide consistent hashing behavior between the userspace and kernel,
	* these functions prepare names for hashing by transforming specific bytes
	* to other bytes. Robustness with other encodings is not guaranteed.
	*/
	static inline bool xfs_ascii_ci_need_xfrm(unsigned char c)
	{
	if (c >= 0x41 && c <= 0x5a) /* A-Z */
	return true;
	if (c >= 0xc0 && c <= 0xd6) /* latin A-O with accents */
	return true;
	if (c >= 0xd8 && c <= 0xde) /* latin O-Y with accents */
	return true;
	return false;
	}

	static inline unsigned char xfs_ascii_ci_xfrm(unsigned char c)
	{
	if (xfs_ascii_ci_need_xfrm(c))
	c -= 'A' - 'a';
	return c;
	}

	#endif /* __XFS_DIR2_H__ */