linux-zen-desktop/fs/xfs/libxfs/xfs_inode_fork.h

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2023-08-30 17:31:07 +02:00
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*/
#ifndef __XFS_INODE_FORK_H__
#define __XFS_INODE_FORK_H__
struct xfs_inode_log_item;
struct xfs_dinode;
/*
* File incore extent information, present for each of data & attr forks.
*/
struct xfs_ifork {
int64_t if_bytes; /* bytes in if_u1 */
struct xfs_btree_block *if_broot; /* file's incore btree root */
unsigned int if_seq; /* fork mod counter */
int if_height; /* height of the extent tree */
union {
void *if_root; /* extent tree root */
char *if_data; /* inline file data */
} if_u1;
xfs_extnum_t if_nextents; /* # of extents in this fork */
short if_broot_bytes; /* bytes allocated for root */
int8_t if_format; /* format of this fork */
};
/*
* Worst-case increase in the fork extent count when we're adding a single
* extent to a fork and there's no possibility of splitting an existing mapping.
*/
#define XFS_IEXT_ADD_NOSPLIT_CNT (1)
/*
* Punching out an extent from the middle of an existing extent can cause the
* extent count to increase by 1.
* i.e. | Old extent | Hole | Old extent |
*/
#define XFS_IEXT_PUNCH_HOLE_CNT (1)
/*
* Adding/removing an xattr can cause XFS_DA_NODE_MAXDEPTH extents to
* be added. One extra extent for dabtree in case a local attr is
* large enough to cause a double split. It can also cause extent
* count to increase proportional to the size of a remote xattr's
* value.
*/
#define XFS_IEXT_ATTR_MANIP_CNT(rmt_blks) \
(XFS_DA_NODE_MAXDEPTH + max(1, rmt_blks))
/*
* A write to a sub-interval of an existing unwritten extent causes the original
* extent to be split into 3 extents
* i.e. | Unwritten | Real | Unwritten |
* Hence extent count can increase by 2.
*/
#define XFS_IEXT_WRITE_UNWRITTEN_CNT (2)
/*
* Moving an extent to data fork can cause a sub-interval of an existing extent
* to be unmapped. This will increase extent count by 1. Mapping in the new
* extent can increase the extent count by 1 again i.e.
* | Old extent | New extent | Old extent |
* Hence number of extents increases by 2.
*/
#define XFS_IEXT_REFLINK_END_COW_CNT (2)
/*
* Removing an initial range of source/donor file's extent and adding a new
* extent (from donor/source file) in its place will cause extent count to
* increase by 1.
*/
#define XFS_IEXT_SWAP_RMAP_CNT (1)
/*
* Fork handling.
*/
#define XFS_IFORK_MAXEXT(ip, w) \
(xfs_inode_fork_size(ip, w) / sizeof(xfs_bmbt_rec_t))
static inline bool xfs_ifork_has_extents(struct xfs_ifork *ifp)
{
return ifp->if_format == XFS_DINODE_FMT_EXTENTS ||
ifp->if_format == XFS_DINODE_FMT_BTREE;
}
static inline xfs_extnum_t xfs_ifork_nextents(struct xfs_ifork *ifp)
{
if (!ifp)
return 0;
return ifp->if_nextents;
}
static inline int8_t xfs_ifork_format(struct xfs_ifork *ifp)
{
if (!ifp)
return XFS_DINODE_FMT_EXTENTS;
return ifp->if_format;
}
static inline xfs_extnum_t xfs_iext_max_nextents(bool has_large_extent_counts,
int whichfork)
{
switch (whichfork) {
case XFS_DATA_FORK:
case XFS_COW_FORK:
if (has_large_extent_counts)
return XFS_MAX_EXTCNT_DATA_FORK_LARGE;
return XFS_MAX_EXTCNT_DATA_FORK_SMALL;
case XFS_ATTR_FORK:
if (has_large_extent_counts)
return XFS_MAX_EXTCNT_ATTR_FORK_LARGE;
return XFS_MAX_EXTCNT_ATTR_FORK_SMALL;
default:
ASSERT(0);
return 0;
}
}
static inline xfs_extnum_t
xfs_dfork_data_extents(
struct xfs_dinode *dip)
{
if (xfs_dinode_has_large_extent_counts(dip))
return be64_to_cpu(dip->di_big_nextents);
return be32_to_cpu(dip->di_nextents);
}
static inline xfs_extnum_t
xfs_dfork_attr_extents(
struct xfs_dinode *dip)
{
if (xfs_dinode_has_large_extent_counts(dip))
return be32_to_cpu(dip->di_big_anextents);
return be16_to_cpu(dip->di_anextents);
}
static inline xfs_extnum_t
xfs_dfork_nextents(
struct xfs_dinode *dip,
int whichfork)
{
switch (whichfork) {
case XFS_DATA_FORK:
return xfs_dfork_data_extents(dip);
case XFS_ATTR_FORK:
return xfs_dfork_attr_extents(dip);
default:
ASSERT(0);
break;
}
return 0;
}
void xfs_ifork_zap_attr(struct xfs_inode *ip);
void xfs_ifork_init_attr(struct xfs_inode *ip, enum xfs_dinode_fmt format,
xfs_extnum_t nextents);
struct xfs_ifork *xfs_iext_state_to_fork(struct xfs_inode *ip, int state);
int xfs_iformat_data_fork(struct xfs_inode *, struct xfs_dinode *);
int xfs_iformat_attr_fork(struct xfs_inode *, struct xfs_dinode *);
void xfs_iflush_fork(struct xfs_inode *, struct xfs_dinode *,
struct xfs_inode_log_item *, int);
void xfs_idestroy_fork(struct xfs_ifork *ifp);
void xfs_idata_realloc(struct xfs_inode *ip, int64_t byte_diff,
int whichfork);
void xfs_iroot_realloc(struct xfs_inode *, int, int);
int xfs_iread_extents(struct xfs_trans *, struct xfs_inode *, int);
int xfs_iextents_copy(struct xfs_inode *, struct xfs_bmbt_rec *,
int);
void xfs_init_local_fork(struct xfs_inode *ip, int whichfork,
const void *data, int64_t size);
xfs_extnum_t xfs_iext_count(struct xfs_ifork *ifp);
void xfs_iext_insert(struct xfs_inode *, struct xfs_iext_cursor *cur,
struct xfs_bmbt_irec *, int);
void xfs_iext_remove(struct xfs_inode *, struct xfs_iext_cursor *,
int);
void xfs_iext_destroy(struct xfs_ifork *);
bool xfs_iext_lookup_extent(struct xfs_inode *ip,
struct xfs_ifork *ifp, xfs_fileoff_t bno,
struct xfs_iext_cursor *cur,
struct xfs_bmbt_irec *gotp);
bool xfs_iext_lookup_extent_before(struct xfs_inode *ip,
struct xfs_ifork *ifp, xfs_fileoff_t *end,
struct xfs_iext_cursor *cur,
struct xfs_bmbt_irec *gotp);
bool xfs_iext_get_extent(struct xfs_ifork *ifp,
struct xfs_iext_cursor *cur,
struct xfs_bmbt_irec *gotp);
void xfs_iext_update_extent(struct xfs_inode *ip, int state,
struct xfs_iext_cursor *cur,
struct xfs_bmbt_irec *gotp);
void xfs_iext_first(struct xfs_ifork *, struct xfs_iext_cursor *);
void xfs_iext_last(struct xfs_ifork *, struct xfs_iext_cursor *);
void xfs_iext_next(struct xfs_ifork *, struct xfs_iext_cursor *);
void xfs_iext_prev(struct xfs_ifork *, struct xfs_iext_cursor *);
static inline bool xfs_iext_next_extent(struct xfs_ifork *ifp,
struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
{
xfs_iext_next(ifp, cur);
return xfs_iext_get_extent(ifp, cur, gotp);
}
static inline bool xfs_iext_prev_extent(struct xfs_ifork *ifp,
struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
{
xfs_iext_prev(ifp, cur);
return xfs_iext_get_extent(ifp, cur, gotp);
}
/*
* Return the extent after cur in gotp without updating the cursor.
*/
static inline bool xfs_iext_peek_next_extent(struct xfs_ifork *ifp,
struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
{
struct xfs_iext_cursor ncur = *cur;
xfs_iext_next(ifp, &ncur);
return xfs_iext_get_extent(ifp, &ncur, gotp);
}
/*
* Return the extent before cur in gotp without updating the cursor.
*/
static inline bool xfs_iext_peek_prev_extent(struct xfs_ifork *ifp,
struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
{
struct xfs_iext_cursor ncur = *cur;
xfs_iext_prev(ifp, &ncur);
return xfs_iext_get_extent(ifp, &ncur, gotp);
}
#define for_each_xfs_iext(ifp, ext, got) \
for (xfs_iext_first((ifp), (ext)); \
xfs_iext_get_extent((ifp), (ext), (got)); \
xfs_iext_next((ifp), (ext)))
extern struct kmem_cache *xfs_ifork_cache;
extern void xfs_ifork_init_cow(struct xfs_inode *ip);
int xfs_ifork_verify_local_data(struct xfs_inode *ip);
int xfs_ifork_verify_local_attr(struct xfs_inode *ip);
int xfs_iext_count_may_overflow(struct xfs_inode *ip, int whichfork,
int nr_to_add);
int xfs_iext_count_upgrade(struct xfs_trans *tp, struct xfs_inode *ip,
uint nr_to_add);
/* returns true if the fork has extents but they are not read in yet. */
static inline bool xfs_need_iread_extents(struct xfs_ifork *ifp)
{
return ifp->if_format == XFS_DINODE_FMT_BTREE && ifp->if_height == 0;
}
#endif /* __XFS_INODE_FORK_H__ */