linux/fs/xfs/libxfs/xfs_dir2.h

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/*
* Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef __XFS_DIR2_H__
#define __XFS_DIR2_H__
#include "xfs_da_format.h"
#include "xfs_da_btree.h"
struct xfs_defer_ops;
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;
extern struct xfs_name xfs_name_dotdot;
/*
* Convert inode mode to directory entry filetype
*/
extern unsigned char xfs_mode_to_ftype(int mode);
xfs: abstract the differences in dir2/dir3 via an ops vector Lots of the dir code now goes through switches to determine what is the correct on-disk format to parse. It generally involves a "xfs_sbversion_hasfoo" check, deferencing the superblock version and feature fields and hence touching several cache lines per operation in the process. Some operations do multiple checks because they nest conditional operations and they don't pass the information in a direct fashion between each other. Hence, add an ops vector to the xfs_inode structure that is configured when the inode is initialised to point to all the correct decode and encoding operations. This will significantly reduce the branchiness and cacheline footprint of the directory object decoding and encoding. This is the first patch in a series of conversion patches. It will introduce the ops structure, the setup of it and add the first operation to the vector. Subsequent patches will convert directory ops one at a time to keep the changes simple and obvious. Just this patch shows the benefit of such an approach on code size. Just converting the two shortform dir operations as this patch does decreases the built binary size by ~1500 bytes: $ size fs/xfs/xfs.o.orig fs/xfs/xfs.o.p1 text data bss dec hex filename 794490 96802 1096 892388 d9de4 fs/xfs/xfs.o.orig 792986 96802 1096 890884 d9804 fs/xfs/xfs.o.p1 $ That's a significant decrease in the instruction cache footprint of the directory code for such a simple change, and indicates that this approach is definitely worth pursuing further. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-10-29 12:11:46 +01:00
/*
* directory operations vector for encode/decode routines
*/
struct xfs_dir_ops {
int (*sf_entsize)(struct xfs_dir2_sf_hdr *hdr, int len);
struct xfs_dir2_sf_entry *
(*sf_nextentry)(struct xfs_dir2_sf_hdr *hdr,
struct xfs_dir2_sf_entry *sfep);
uint8_t (*sf_get_ftype)(struct xfs_dir2_sf_entry *sfep);
void (*sf_put_ftype)(struct xfs_dir2_sf_entry *sfep,
uint8_t ftype);
xfs_ino_t (*sf_get_ino)(struct xfs_dir2_sf_hdr *hdr,
struct xfs_dir2_sf_entry *sfep);
void (*sf_put_ino)(struct xfs_dir2_sf_hdr *hdr,
struct xfs_dir2_sf_entry *sfep,
xfs_ino_t ino);
xfs_ino_t (*sf_get_parent_ino)(struct xfs_dir2_sf_hdr *hdr);
void (*sf_put_parent_ino)(struct xfs_dir2_sf_hdr *hdr,
xfs_ino_t ino);
int (*data_entsize)(int len);
uint8_t (*data_get_ftype)(struct xfs_dir2_data_entry *dep);
void (*data_put_ftype)(struct xfs_dir2_data_entry *dep,
uint8_t ftype);
__be16 * (*data_entry_tag_p)(struct xfs_dir2_data_entry *dep);
struct xfs_dir2_data_free *
(*data_bestfree_p)(struct xfs_dir2_data_hdr *hdr);
xfs_dir2_data_aoff_t data_dot_offset;
xfs_dir2_data_aoff_t data_dotdot_offset;
xfs_dir2_data_aoff_t data_first_offset;
size_t data_entry_offset;
struct xfs_dir2_data_entry *
(*data_dot_entry_p)(struct xfs_dir2_data_hdr *hdr);
struct xfs_dir2_data_entry *
(*data_dotdot_entry_p)(struct xfs_dir2_data_hdr *hdr);
struct xfs_dir2_data_entry *
(*data_first_entry_p)(struct xfs_dir2_data_hdr *hdr);
struct xfs_dir2_data_entry *
(*data_entry_p)(struct xfs_dir2_data_hdr *hdr);
struct xfs_dir2_data_unused *
(*data_unused_p)(struct xfs_dir2_data_hdr *hdr);
int leaf_hdr_size;
void (*leaf_hdr_to_disk)(struct xfs_dir2_leaf *to,
struct xfs_dir3_icleaf_hdr *from);
void (*leaf_hdr_from_disk)(struct xfs_dir3_icleaf_hdr *to,
struct xfs_dir2_leaf *from);
int (*leaf_max_ents)(struct xfs_da_geometry *geo);
struct xfs_dir2_leaf_entry *
(*leaf_ents_p)(struct xfs_dir2_leaf *lp);
int node_hdr_size;
void (*node_hdr_to_disk)(struct xfs_da_intnode *to,
struct xfs_da3_icnode_hdr *from);
void (*node_hdr_from_disk)(struct xfs_da3_icnode_hdr *to,
struct xfs_da_intnode *from);
struct xfs_da_node_entry *
(*node_tree_p)(struct xfs_da_intnode *dap);
int free_hdr_size;
void (*free_hdr_to_disk)(struct xfs_dir2_free *to,
struct xfs_dir3_icfree_hdr *from);
void (*free_hdr_from_disk)(struct xfs_dir3_icfree_hdr *to,
struct xfs_dir2_free *from);
int (*free_max_bests)(struct xfs_da_geometry *geo);
__be16 * (*free_bests_p)(struct xfs_dir2_free *free);
xfs_dir2_db_t (*db_to_fdb)(struct xfs_da_geometry *geo,
xfs_dir2_db_t db);
int (*db_to_fdindex)(struct xfs_da_geometry *geo,
xfs_dir2_db_t db);
xfs: abstract the differences in dir2/dir3 via an ops vector Lots of the dir code now goes through switches to determine what is the correct on-disk format to parse. It generally involves a "xfs_sbversion_hasfoo" check, deferencing the superblock version and feature fields and hence touching several cache lines per operation in the process. Some operations do multiple checks because they nest conditional operations and they don't pass the information in a direct fashion between each other. Hence, add an ops vector to the xfs_inode structure that is configured when the inode is initialised to point to all the correct decode and encoding operations. This will significantly reduce the branchiness and cacheline footprint of the directory object decoding and encoding. This is the first patch in a series of conversion patches. It will introduce the ops structure, the setup of it and add the first operation to the vector. Subsequent patches will convert directory ops one at a time to keep the changes simple and obvious. Just this patch shows the benefit of such an approach on code size. Just converting the two shortform dir operations as this patch does decreases the built binary size by ~1500 bytes: $ size fs/xfs/xfs.o.orig fs/xfs/xfs.o.p1 text data bss dec hex filename 794490 96802 1096 892388 d9de4 fs/xfs/xfs.o.orig 792986 96802 1096 890884 d9804 fs/xfs/xfs.o.p1 $ That's a significant decrease in the instruction cache footprint of the directory code for such a simple change, and indicates that this approach is definitely worth pursuing further. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-10-29 12:11:46 +01:00
};
extern const struct xfs_dir_ops *
xfs_dir_get_ops(struct xfs_mount *mp, struct xfs_inode *dp);
extern const struct xfs_dir_ops *
xfs_nondir_get_ops(struct xfs_mount *mp, struct xfs_inode *dp);
xfs: abstract the differences in dir2/dir3 via an ops vector Lots of the dir code now goes through switches to determine what is the correct on-disk format to parse. It generally involves a "xfs_sbversion_hasfoo" check, deferencing the superblock version and feature fields and hence touching several cache lines per operation in the process. Some operations do multiple checks because they nest conditional operations and they don't pass the information in a direct fashion between each other. Hence, add an ops vector to the xfs_inode structure that is configured when the inode is initialised to point to all the correct decode and encoding operations. This will significantly reduce the branchiness and cacheline footprint of the directory object decoding and encoding. This is the first patch in a series of conversion patches. It will introduce the ops structure, the setup of it and add the first operation to the vector. Subsequent patches will convert directory ops one at a time to keep the changes simple and obvious. Just this patch shows the benefit of such an approach on code size. Just converting the two shortform dir operations as this patch does decreases the built binary size by ~1500 bytes: $ size fs/xfs/xfs.o.orig fs/xfs/xfs.o.p1 text data bss dec hex filename 794490 96802 1096 892388 d9de4 fs/xfs/xfs.o.orig 792986 96802 1096 890884 d9804 fs/xfs/xfs.o.p1 $ That's a significant decrease in the instruction cache footprint of the directory code for such a simple change, and indicates that this approach is definitely worth pursuing further. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-10-29 12:11:46 +01:00
/*
* 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,
struct xfs_name *name, xfs_ino_t inum,
xfs_fsblock_t *first,
struct xfs_defer_ops *dfops, xfs_extlen_t tot);
extern int xfs_dir_lookup(struct xfs_trans *tp, struct xfs_inode *dp,
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_fsblock_t *first,
struct xfs_defer_ops *dfops, xfs_extlen_t tot);
extern int xfs_dir_replace(struct xfs_trans *tp, struct xfs_inode *dp,
struct xfs_name *name, xfs_ino_t inum,
xfs_fsblock_t *first,
struct xfs_defer_ops *dfops, 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_int(struct xfs_da_geometry *geo,
const struct xfs_dir_ops *ops,
struct xfs_dir2_data_hdr *hdr, int *loghead);
extern void xfs_dir2_data_freescan(struct xfs_inode *dp,
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);
void *xfs_dir3_data_endp(struct xfs_da_geometry *geo,
struct xfs_dir2_data_hdr *hdr);
#endif /* __XFS_DIR2_H__ */