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/* SPDX-License-Identifier: GPL-2.0
*
* linux/drivers/staging/erofs/internal.h
*
* Copyright (C) 2017-2018 HUAWEI, Inc.
* http://www.huawei.com/
* Created by Gao Xiang <gaoxiang25@huawei.com>
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of the Linux
* distribution for more details.
*/
#ifndef __INTERNAL_H
#define __INTERNAL_H
#include <linux/fs.h>
#include <linux/dcache.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
#include <linux/bio.h>
#include <linux/buffer_head.h>
#include <linux/cleancache.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include "erofs_fs.h"
/* redefine pr_fmt "erofs: " */
#undef pr_fmt
#define pr_fmt(fmt) "erofs: " fmt
#define errln(x, ...) pr_err(x "\n", ##__VA_ARGS__)
#define infoln(x, ...) pr_info(x "\n", ##__VA_ARGS__)
#ifdef CONFIG_EROFS_FS_DEBUG
#define debugln(x, ...) pr_debug(x "\n", ##__VA_ARGS__)
#define dbg_might_sleep might_sleep
#define DBG_BUGON BUG_ON
#else
#define debugln(x, ...) ((void)0)
#define dbg_might_sleep() ((void)0)
#define DBG_BUGON(x) ((void)(x))
#endif
enum {
FAULT_KMALLOC,
FAULT_MAX,
};
#ifdef CONFIG_EROFS_FAULT_INJECTION
extern char *erofs_fault_name[FAULT_MAX];
#define IS_FAULT_SET(fi, type) ((fi)->inject_type & (1 << (type)))
struct erofs_fault_info {
atomic_t inject_ops;
unsigned int inject_rate;
unsigned int inject_type;
};
#endif
#ifdef CONFIG_EROFS_FS_ZIP_CACHE_BIPOLAR
#define EROFS_FS_ZIP_CACHE_LVL (2)
#elif defined(EROFS_FS_ZIP_CACHE_UNIPOLAR)
#define EROFS_FS_ZIP_CACHE_LVL (1)
#else
#define EROFS_FS_ZIP_CACHE_LVL (0)
#endif
#if (!defined(EROFS_FS_HAS_MANAGED_CACHE) && (EROFS_FS_ZIP_CACHE_LVL > 0))
#define EROFS_FS_HAS_MANAGED_CACHE
#endif
/* EROFS_SUPER_MAGIC_V1 to represent the whole file system */
#define EROFS_SUPER_MAGIC EROFS_SUPER_MAGIC_V1
typedef u64 erofs_nid_t;
struct erofs_sb_info {
/* list for all registered superblocks, mainly for shrinker */
struct list_head list;
struct mutex umount_mutex;
u32 blocks;
u32 meta_blkaddr;
#ifdef CONFIG_EROFS_FS_XATTR
u32 xattr_blkaddr;
#endif
/* inode slot unit size in bit shift */
unsigned char islotbits;
#ifdef CONFIG_EROFS_FS_ZIP
/* cluster size in bit shift */
unsigned char clusterbits;
/* the dedicated workstation for compression */
struct radix_tree_root workstn_tree;
/* threshold for decompression synchronously */
unsigned int max_sync_decompress_pages;
#ifdef EROFS_FS_HAS_MANAGED_CACHE
struct inode *managed_cache;
#endif
#endif
u32 build_time_nsec;
u64 build_time;
/* what we really care is nid, rather than ino.. */
erofs_nid_t root_nid;
/* used for statfs, f_files - f_favail */
u64 inos;
u8 uuid[16]; /* 128-bit uuid for volume */
u8 volume_name[16]; /* volume name */
char *dev_name;
unsigned int mount_opt;
unsigned int shrinker_run_no;
#ifdef CONFIG_EROFS_FAULT_INJECTION
struct erofs_fault_info fault_info; /* For fault injection */
#endif
};
#ifdef CONFIG_EROFS_FAULT_INJECTION
#define erofs_show_injection_info(type) \
infoln("inject %s in %s of %pS", erofs_fault_name[type], \
__func__, __builtin_return_address(0))
static inline bool time_to_inject(struct erofs_sb_info *sbi, int type)
{
struct erofs_fault_info *ffi = &sbi->fault_info;
if (!ffi->inject_rate)
return false;
if (!IS_FAULT_SET(ffi, type))
return false;
atomic_inc(&ffi->inject_ops);
if (atomic_read(&ffi->inject_ops) >= ffi->inject_rate) {
atomic_set(&ffi->inject_ops, 0);
return true;
}
return false;
}
#else
static inline bool time_to_inject(struct erofs_sb_info *sbi, int type)
{
return false;
}
static inline void erofs_show_injection_info(int type)
{
}
#endif
static inline void *erofs_kmalloc(struct erofs_sb_info *sbi,
size_t size, gfp_t flags)
{
if (time_to_inject(sbi, FAULT_KMALLOC)) {
erofs_show_injection_info(FAULT_KMALLOC);
return NULL;
}
return kmalloc(size, flags);
}
#define EROFS_SB(sb) ((struct erofs_sb_info *)(sb)->s_fs_info)
#define EROFS_I_SB(inode) ((struct erofs_sb_info *)(inode)->i_sb->s_fs_info)
/* Mount flags set via mount options or defaults */
#define EROFS_MOUNT_XATTR_USER 0x00000010
#define EROFS_MOUNT_POSIX_ACL 0x00000020
#define EROFS_MOUNT_FAULT_INJECTION 0x00000040
#define clear_opt(sbi, option) ((sbi)->mount_opt &= ~EROFS_MOUNT_##option)
#define set_opt(sbi, option) ((sbi)->mount_opt |= EROFS_MOUNT_##option)
#define test_opt(sbi, option) ((sbi)->mount_opt & EROFS_MOUNT_##option)
#ifdef CONFIG_EROFS_FS_ZIP
#define erofs_workstn_lock(sbi) xa_lock(&(sbi)->workstn_tree)
#define erofs_workstn_unlock(sbi) xa_unlock(&(sbi)->workstn_tree)
/* basic unit of the workstation of a super_block */
struct erofs_workgroup {
/* the workgroup index in the workstation */
pgoff_t index;
/* overall workgroup reference count */
atomic_t refcount;
};
#define EROFS_LOCKED_MAGIC (INT_MIN | 0xE0F510CCL)
#if defined(CONFIG_SMP)
static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp,
int val)
{
preempt_disable();
if (val != atomic_cmpxchg(&grp->refcount, val, EROFS_LOCKED_MAGIC)) {
preempt_enable();
return false;
}
return true;
}
static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp,
int orig_val)
{
/*
* other observers should notice all modifications
* in the freezing period.
*/
smp_mb();
atomic_set(&grp->refcount, orig_val);
preempt_enable();
}
static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp)
{
return atomic_cond_read_relaxed(&grp->refcount,
VAL != EROFS_LOCKED_MAGIC);
}
#else
static inline bool erofs_workgroup_try_to_freeze(struct erofs_workgroup *grp,
int val)
{
preempt_disable();
/* no need to spin on UP platforms, let's just disable preemption. */
if (val != atomic_read(&grp->refcount)) {
preempt_enable();
return false;
}
return true;
}
static inline void erofs_workgroup_unfreeze(struct erofs_workgroup *grp,
int orig_val)
{
preempt_enable();
}
static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp)
{
int v = atomic_read(&grp->refcount);
/* workgroup is never freezed on uniprocessor systems */
DBG_BUGON(v == EROFS_LOCKED_MAGIC);
return v;
}
#endif
int erofs_workgroup_put(struct erofs_workgroup *grp);
struct erofs_workgroup *erofs_find_workgroup(struct super_block *sb,
pgoff_t index, bool *tag);
int erofs_register_workgroup(struct super_block *sb,
struct erofs_workgroup *grp, bool tag);
unsigned long erofs_shrink_workstation(struct erofs_sb_info *sbi,
unsigned long nr_shrink, bool cleanup);
void erofs_workgroup_free_rcu(struct erofs_workgroup *grp);
#ifdef EROFS_FS_HAS_MANAGED_CACHE
int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi,
struct erofs_workgroup *egrp);
int erofs_try_to_free_cached_page(struct address_space *mapping,
struct page *page);
#define MNGD_MAPPING(sbi) ((sbi)->managed_cache->i_mapping)
static inline bool erofs_page_is_managed(const struct erofs_sb_info *sbi,
struct page *page)
{
return page->mapping == MNGD_MAPPING(sbi);
}
#else
#define MNGD_MAPPING(sbi) (NULL)
static inline bool erofs_page_is_managed(const struct erofs_sb_info *sbi,
struct page *page) { return false; }
#endif
#define DEFAULT_MAX_SYNC_DECOMPRESS_PAGES 3
static inline bool __should_decompress_synchronously(struct erofs_sb_info *sbi,
unsigned int nr)
{
return nr <= sbi->max_sync_decompress_pages;
}
int __init z_erofs_init_zip_subsystem(void);
void z_erofs_exit_zip_subsystem(void);
#else
/* dummy initializer/finalizer for the decompression subsystem */
static inline int z_erofs_init_zip_subsystem(void) { return 0; }
static inline void z_erofs_exit_zip_subsystem(void) {}
#endif
/* we strictly follow PAGE_SIZE and no buffer head yet */
#define LOG_BLOCK_SIZE PAGE_SHIFT
#undef LOG_SECTORS_PER_BLOCK
#define LOG_SECTORS_PER_BLOCK (PAGE_SHIFT - 9)
#undef SECTORS_PER_BLOCK
#define SECTORS_PER_BLOCK (1 << SECTORS_PER_BLOCK)
#define EROFS_BLKSIZ (1 << LOG_BLOCK_SIZE)
#if (EROFS_BLKSIZ % 4096 || !EROFS_BLKSIZ)
#error erofs cannot be used in this platform
#endif
#define ROOT_NID(sb) ((sb)->root_nid)
#ifdef CONFIG_EROFS_FS_ZIP
/* hard limit of pages per compressed cluster */
#define Z_EROFS_CLUSTER_MAX_PAGES (CONFIG_EROFS_FS_CLUSTER_PAGE_LIMIT)
/* page count of a compressed cluster */
#define erofs_clusterpages(sbi) ((1 << (sbi)->clusterbits) / PAGE_SIZE)
#endif
typedef u64 erofs_off_t;
/* data type for filesystem-wide blocks number */
typedef u32 erofs_blk_t;
#define erofs_blknr(addr) ((addr) / EROFS_BLKSIZ)
#define erofs_blkoff(addr) ((addr) % EROFS_BLKSIZ)
#define blknr_to_addr(nr) ((erofs_off_t)(nr) * EROFS_BLKSIZ)
static inline erofs_off_t iloc(struct erofs_sb_info
|