linux-stable/fs/bcachefs/fs.h
Kent Overstreet a7ecd30c83 bcachefs: Factor out two_state_shared_lock
We have a unique lock used for controlling adding to the pagecache: the
lock has two states, where both states are shared - the lock may be held
multiple times for either state - but not both states at the same time.

This is exactly what we need for nocow mode locking, so this patch pulls
it out of fs.c into its own file.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:09:45 -04:00

194 lines
5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _BCACHEFS_FS_H
#define _BCACHEFS_FS_H
#include "inode.h"
#include "opts.h"
#include "str_hash.h"
#include "quota_types.h"
#include "two_state_shared_lock.h"
#include <linux/seqlock.h>
#include <linux/stat.h>
struct bch_inode_info {
struct inode v;
unsigned long ei_flags;
struct mutex ei_update_lock;
u64 ei_quota_reserved;
unsigned long ei_last_dirtied;
two_state_lock_t ei_pagecache_lock;
struct mutex ei_quota_lock;
struct bch_qid ei_qid;
u32 ei_subvol;
/* copy of inode in btree: */
struct bch_inode_unpacked ei_inode;
};
#define bch2_pagecache_add_put(i) bch2_two_state_unlock(&i->ei_pagecache_lock, 0)
#define bch2_pagecache_add_tryget(i) bch2_two_state_trylock(&i->ei_pagecache_lock, 0)
#define bch2_pagecache_add_get(i) bch2_two_state_lock(&i->ei_pagecache_lock, 0)
#define bch2_pagecache_block_put(i) bch2_two_state_unlock(&i->ei_pagecache_lock, 1)
#define bch2_pagecache_block_get(i) bch2_two_state_lock(&i->ei_pagecache_lock, 1)
static inline subvol_inum inode_inum(struct bch_inode_info *inode)
{
return (subvol_inum) {
.subvol = inode->ei_subvol,
.inum = inode->ei_inode.bi_inum,
};
}
/*
* Set if we've gotten a btree error for this inode, and thus the vfs inode and
* btree inode may be inconsistent:
*/
#define EI_INODE_ERROR 0
/*
* Set in the inode is in a snapshot subvolume - we don't do quota accounting in
* those:
*/
#define EI_INODE_SNAPSHOT 1
#define to_bch_ei(_inode) \
container_of_or_null(_inode, struct bch_inode_info, v)
static inline int ptrcmp(void *l, void *r)
{
return cmp_int(l, r);
}
enum bch_inode_lock_op {
INODE_LOCK = (1U << 0),
INODE_PAGECACHE_BLOCK = (1U << 1),
INODE_UPDATE_LOCK = (1U << 2),
};
#define bch2_lock_inodes(_locks, ...) \
do { \
struct bch_inode_info *a[] = { NULL, __VA_ARGS__ }; \
unsigned i; \
\
bubble_sort(&a[1], ARRAY_SIZE(a) - 1, ptrcmp); \
\
for (i = 1; i < ARRAY_SIZE(a); i++) \
if (a[i] != a[i - 1]) { \
if ((_locks) & INODE_LOCK) \
down_write_nested(&a[i]->v.i_rwsem, i); \
if ((_locks) & INODE_PAGECACHE_BLOCK) \
bch2_pagecache_block_get(a[i]);\
if ((_locks) & INODE_UPDATE_LOCK) \
mutex_lock_nested(&a[i]->ei_update_lock, i);\
} \
} while (0)
#define bch2_unlock_inodes(_locks, ...) \
do { \
struct bch_inode_info *a[] = { NULL, __VA_ARGS__ }; \
unsigned i; \
\
bubble_sort(&a[1], ARRAY_SIZE(a) - 1, ptrcmp); \
\
for (i = 1; i < ARRAY_SIZE(a); i++) \
if (a[i] != a[i - 1]) { \
if ((_locks) & INODE_LOCK) \
up_write(&a[i]->v.i_rwsem); \
if ((_locks) & INODE_PAGECACHE_BLOCK) \
bch2_pagecache_block_put(a[i]);\
if ((_locks) & INODE_UPDATE_LOCK) \
mutex_unlock(&a[i]->ei_update_lock); \
} \
} while (0)
static inline struct bch_inode_info *file_bch_inode(struct file *file)
{
return to_bch_ei(file_inode(file));
}
static inline bool inode_attr_changing(struct bch_inode_info *dir,
struct bch_inode_info *inode,
enum inode_opt_id id)
{
return !(inode->ei_inode.bi_fields_set & (1 << id)) &&
bch2_inode_opt_get(&dir->ei_inode, id) !=
bch2_inode_opt_get(&inode->ei_inode, id);
}
static inline bool inode_attrs_changing(struct bch_inode_info *dir,
struct bch_inode_info *inode)
{
unsigned id;
for (id = 0; id < Inode_opt_nr; id++)
if (inode_attr_changing(dir, inode, id))
return true;
return false;
}
struct bch_inode_unpacked;
#ifndef NO_BCACHEFS_FS
struct bch_inode_info *
__bch2_create(struct mnt_idmap *, struct bch_inode_info *,
struct dentry *, umode_t, dev_t, subvol_inum, unsigned);
int bch2_fs_quota_transfer(struct bch_fs *,
struct bch_inode_info *,
struct bch_qid,
unsigned,
enum quota_acct_mode);
static inline int bch2_set_projid(struct bch_fs *c,
struct bch_inode_info *inode,
u32 projid)
{
struct bch_qid qid = inode->ei_qid;
qid.q[QTYP_PRJ] = projid;
return bch2_fs_quota_transfer(c, inode, qid,
1 << QTYP_PRJ,
KEY_TYPE_QUOTA_PREALLOC);
}
struct inode *bch2_vfs_inode_get(struct bch_fs *, subvol_inum);
/* returns 0 if we want to do the update, or error is passed up */
typedef int (*inode_set_fn)(struct bch_inode_info *,
struct bch_inode_unpacked *, void *);
void bch2_inode_update_after_write(struct btree_trans *,
struct bch_inode_info *,
struct bch_inode_unpacked *,
unsigned);
int __must_check bch2_write_inode(struct bch_fs *, struct bch_inode_info *,
inode_set_fn, void *, unsigned);
int bch2_setattr_nonsize(struct mnt_idmap *,
struct bch_inode_info *,
struct iattr *);
int __bch2_unlink(struct inode *, struct dentry *, bool);
void bch2_evict_subvolume_inodes(struct bch_fs *, snapshot_id_list *);
void bch2_vfs_exit(void);
int bch2_vfs_init(void);
#else
static inline void bch2_evict_subvolume_inodes(struct bch_fs *c,
snapshot_id_list *s) {}
static inline void bch2_vfs_exit(void) {}
static inline int bch2_vfs_init(void) { return 0; }
#endif /* NO_BCACHEFS_FS */
#endif /* _BCACHEFS_FS_H */