Orange Pi5 kernel

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright 2019 Google LLC
 */
#ifndef _INCFS_DATA_MGMT_H
#define _INCFS_DATA_MGMT_H
 
#include <linux/cred.h>
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/rcupdate.h>
#include <linux/completion.h>
#include <linux/wait.h>
#include <linux/zstd.h>
#include <crypto/hash.h>
#include <linux/rwsem.h>
 
#include <uapi/linux/incrementalfs.h>
 
#include "internal.h"
#include "pseudo_files.h"
 
#define SEGMENTS_PER_FILE 3
 
enum LOG_RECORD_TYPE {
<------>FULL,
<------>SAME_FILE,
<------>SAME_FILE_CLOSE_BLOCK,
<------>SAME_FILE_CLOSE_BLOCK_SHORT,
<------>SAME_FILE_NEXT_BLOCK,
<------>SAME_FILE_NEXT_BLOCK_SHORT,
};
 
struct full_record {
<------>enum LOG_RECORD_TYPE type : 3; /* FULL */
<------>u32 block_index : 29;
<------>incfs_uuid_t file_id;
<------>u64 absolute_ts_us;
<------>uid_t uid;
} __packed; /* 32 bytes */
 
struct same_file {
<------>enum LOG_RECORD_TYPE type : 3; /* SAME_FILE */
<------>u32 block_index : 29;
<------>uid_t uid;
<------>u16 relative_ts_us; /* max 2^16 us ~= 64 ms */
} __packed; /* 10 bytes */
 
struct same_file_close_block {
<------>enum LOG_RECORD_TYPE type : 3; /* SAME_FILE_CLOSE_BLOCK */
<------>u16 relative_ts_us : 13; /* max 2^13 us ~= 8 ms */
<------>s16 block_index_delta;
} __packed; /* 4 bytes */
 
struct same_file_close_block_short {
<------>enum LOG_RECORD_TYPE type : 3; /* SAME_FILE_CLOSE_BLOCK_SHORT */
<------>u8 relative_ts_tens_us : 5; /* max 2^5*10 us ~= 320 us */
<------>s8 block_index_delta;
} __packed; /* 2 bytes */
 
struct same_file_next_block {
<------>enum LOG_RECORD_TYPE type : 3; /* SAME_FILE_NEXT_BLOCK */
<------>u16 relative_ts_us : 13; /* max 2^13 us ~= 8 ms */
} __packed; /* 2 bytes */
 
struct same_file_next_block_short {
<------>enum LOG_RECORD_TYPE type : 3; /* SAME_FILE_NEXT_BLOCK_SHORT */
<------>u8 relative_ts_tens_us : 5; /* max 2^5*10 us ~= 320 us */
} __packed; /* 1 byte */
 
union log_record {
<------>struct full_record full_record;
<------>struct same_file same_file;
<------>struct same_file_close_block same_file_close_block;
<------>struct same_file_close_block_short same_file_close_block_short;
<------>struct same_file_next_block same_file_next_block;
<------>struct same_file_next_block_short same_file_next_block_short;
};
 
struct read_log_state {
<------>/* Log buffer generation id, incremented on configuration changes */
<------>u32 generation_id;
 
<------>/* Offset in rl_ring_buf to write into. */
<------>u32 next_offset;
 
<------>/* Current number of writer passes over rl_ring_buf */
<------>u32 current_pass_no;
 
<------>/* Current full_record to diff against */
<------>struct full_record base_record;
 
<------>/* Current record number counting from configuration change */
<------>u64 current_record_no;
};
 
/* A ring buffer to save records about data blocks which were recently read. */
struct read_log {
<------>void *rl_ring_buf;
 
<------>int rl_size;
 
<------>struct read_log_state rl_head;
 
<------>struct read_log_state rl_tail;
 
<------>/* A lock to protect the above fields */
<------>spinlock_t rl_lock;
 
<------>/* A queue of waiters who want to be notified about reads */
<------>wait_queue_head_t ml_notif_wq;
 
<------>/* A work item to wake up those waiters without slowing down readers */
<------>struct delayed_work ml_wakeup_work;
};
 
struct mount_options {
<------>unsigned int read_timeout_ms;
<------>unsigned int readahead_pages;
<------>unsigned int read_log_pages;
<------>unsigned int read_log_wakeup_count;
<------>bool report_uid;
<------>char *sysfs_name;
};
 
struct mount_info {
<------>struct super_block *mi_sb;
 
<------>struct path mi_backing_dir_path;
 
<------>struct dentry *mi_index_dir;
<------>/* For stacking mounts, if true, this indicates if the index dir needs
<------> * to be freed for this SB otherwise it was created by lower level SB */
<------>bool mi_index_free;
 
<------>struct dentry *mi_incomplete_dir;
<------>/* For stacking mounts, if true, this indicates if the incomplete dir
<------> * needs to be freed for this SB. Similar to mi_index_free */
<------>bool mi_incomplete_free;
 
<------>const struct cred *mi_owner;
 
<------>struct mount_options mi_options;
 
<------>/* This mutex is to be taken before create, rename, delete */
<------>struct mutex mi_dir_struct_mutex;
 
<------>/*
<------> * A queue of waiters who want to be notified about new pending reads.
<------> */
<------>wait_queue_head_t mi_pending_reads_notif_wq;
 
<------>/*
<------> * Protects - RCU safe:
<------> *  - reads_list_head
<------> *  - mi_pending_reads_count
<------> *  - mi_last_pending_read_number
<------> *  - data_file_segment.reads_list_head
<------> */
<------>spinlock_t pending_read_lock;
 
<------>/* List of active pending_read objects */
<------>struct list_head mi_reads_list_head;
 
<------>/* Total number of items in reads_list_head */
<------>int mi_pending_reads_count;
 
<------>/*
<------> * Last serial number that was assigned to a pending read.
<------> * 0 means no pending reads have been seen yet.
<------> */
<------>int mi_last_pending_read_number;
 
<------>/* Temporary buffer for read logger. */
<------>struct read_log mi_log;
 
<------>/* SELinux needs special xattrs on our pseudo files */
<------>struct mem_range pseudo_file_xattr[PSEUDO_FILE_COUNT];
 
<------>/* A queue of waiters who want to be notified about blocks_written */
<------>wait_queue_head_t mi_blocks_written_notif_wq;
 
<------>/* Number of blocks written since mount */
<------>atomic_t mi_blocks_written;
 
<------>/* Per UID read timeouts */
<------>spinlock_t mi_per_uid_read_timeouts_lock;
<------>struct incfs_per_uid_read_timeouts *mi_per_uid_read_timeouts;
<------>int mi_per_uid_read_timeouts_size;
 
<------>/* zstd workspace */
<------>struct mutex mi_zstd_workspace_mutex;
<------>void *mi_zstd_workspace;
<------>ZSTD_DStream *mi_zstd_stream;
<------>struct delayed_work mi_zstd_cleanup_work;
 
<------>/* sysfs node */
<------>struct incfs_sysfs_node *mi_sysfs_node;
 
<------>/* Last error information */
<------>struct mutex	mi_le_mutex;
<------>incfs_uuid_t	mi_le_file_id;
<------>u64		mi_le_time_us;
<------>u32		mi_le_page;
<------>u32		mi_le_errno;
<------>uid_t		mi_le_uid;
 
<------>/* Number of reads timed out */
<------>u32 mi_reads_failed_timed_out;
 
<------>/* Number of reads failed because hash verification failed */
<------>u32 mi_reads_failed_hash_verification;
 
<------>/* Number of reads failed for another reason */
<------>u32 mi_reads_failed_other;
 
<------>/* Number of reads delayed because page had to be fetched */
<------>u32 mi_reads_delayed_pending;
 
<------>/* Total time waiting for pages to be fetched */
<------>u64 mi_reads_delayed_pending_us;
 
<------>/*
<------> * Number of reads delayed because of per-uid min_time_us or
<------> * min_pending_time_us settings
<------> */
<------>u32 mi_reads_delayed_min;
 
<------>/* Total time waiting because of per-uid min_time_us or
<------> * min_pending_time_us settings.
<------> *
<------> * Note that if a read is initially delayed because we have to wait for
<------> * the page, then further delayed because of min_pending_time_us
<------> * setting, this counter gets incremented by only the further delay
<------> * time.
<------> */
<------>u64 mi_reads_delayed_min_us;
};
 
struct data_file_block {
<------>loff_t db_backing_file_data_offset;
 
<------>size_t db_stored_size;
 
<------>enum incfs_compression_alg db_comp_alg;
};
 
struct pending_read {
<------>incfs_uuid_t file_id;
 
<------>s64 timestamp_us;
 
<------>atomic_t done;
 
<------>int block_index;
 
<------>int serial_number;
 
<------>uid_t uid;
 
<------>struct list_head mi_reads_list;
 
<------>struct list_head segment_reads_list;
 
<------>struct rcu_head rcu;
};
 
struct data_file_segment {
<------>wait_queue_head_t new_data_arrival_wq;
 
<------>/* Protects reads and writes from the blockmap */
<------>struct rw_semaphore rwsem;
 
<------>/* List of active pending_read objects belonging to this segment */
<------>/* Protected by mount_info.pending_reads_mutex */
<------>struct list_head reads_list_head;
};
 
/*
 * Extra info associated with a file. Just a few bytes set by a user.
 */
struct file_attr {
<------>loff_t fa_value_offset;
 
<------>size_t fa_value_size;
 
<------>u32 fa_crc;
};
 
 
struct data_file {
<------>struct backing_file_context *df_backing_file_context;
 
<------>struct mount_info *df_mount_info;
 
<------>incfs_uuid_t df_id;
 
<------>/*
<------> * Array of segments used to reduce lock contention for the file.
<------> * Segment is chosen for a block depends on the block's index.
<------> */
<------>struct data_file_segment df_segments[SEGMENTS_PER_FILE];
 
<------>/* Base offset of the first metadata record. */
<------>loff_t df_metadata_off;
 
<------>/* Base offset of the block map. */
<------>loff_t df_blockmap_off;
 
<------>/* File size in bytes */
<------>loff_t df_size;
 
<------>/* File header flags */
<------>u32 df_header_flags;
 
<------>/* File size in DATA_FILE_BLOCK_SIZE blocks */
<------>int df_data_block_count;
 
<------>/* Total number of blocks, data + hash */
<------>int df_total_block_count;
 
<------>/* For mapped files, the offset into the actual file */
<------>loff_t df_mapped_offset;
 
<------>/* Number of data blocks written to file */
<------>atomic_t df_data_blocks_written;
 
<------>/* Number of data blocks in the status block */
<------>u32 df_initial_data_blocks_written;
 
<------>/* Number of hash blocks written to file */
<------>atomic_t df_hash_blocks_written;
 
<------>/* Number of hash blocks in the status block */
<------>u32 df_initial_hash_blocks_written;
 
<------>/* Offset to status metadata header */
<------>loff_t df_status_offset;
 
<------>/*
<------> * Mutex acquired while enabling verity. Note that df_hash_tree is set
<------> * by enable verity.
<------> *
<------> * The backing file mutex bc_mutex  may be taken while this mutex is
<------> * held.
<------> */
<------>struct mutex df_enable_verity;
 
<------>/*
<------> * Set either at construction time or during enabling verity. In the
<------> * latter case, set via smp_store_release, so use smp_load_acquire to
<------> * read it.
<------> */
<------>struct mtree *df_hash_tree;
 
<------>/* Guaranteed set if df_hash_tree is set. */
<------>struct incfs_df_signature *df_signature;
 
<------>/*
<------> * The verity file digest, set when verity is enabled and the file has
<------> * been opened
<------> */
<------>struct mem_range df_verity_file_digest;
 
<------>struct incfs_df_verity_signature *df_verity_signature;
};
 
struct dir_file {
<------>struct mount_info *mount_info;
 
<------>struct file *backing_dir;
};
 
struct inode_info {
<------>struct mount_info *n_mount_info; /* A mount, this file belongs to */
 
<------>struct inode *n_backing_inode;
 
<------>struct data_file *n_file;
 
<------>struct inode n_vfs_inode;
};
 
struct dentry_info {
<------>struct path backing_path;
};
 
enum FILL_PERMISSION {
<------>CANT_FILL = 0,
<------>CAN_FILL = 1,
};
 
struct incfs_file_data {
<------>/* Does this file handle have INCFS_IOC_FILL_BLOCKS permission */
<------>enum FILL_PERMISSION fd_fill_permission;
 
<------>/* If INCFS_IOC_GET_FILLED_BLOCKS has been called, where are we */
<------>int fd_get_block_pos;
 
<------>/* And how many filled blocks are there up to that point */
<------>int fd_filled_data_blocks;
<------>int fd_filled_hash_blocks;
};
 
struct mount_info *incfs_alloc_mount_info(struct super_block *sb,
<------><------><------><------><------>  struct mount_options *options,
<------><------><------><------><------>  struct path *backing_dir_path);
 
int incfs_realloc_mount_info(struct mount_info *mi,
<------><------><------>     struct mount_options *options);
 
void incfs_free_mount_info(struct mount_info *mi);
 
char *file_id_to_str(incfs_uuid_t id);
struct dentry *incfs_lookup_dentry(struct dentry *parent, const char *name);
struct data_file *incfs_open_data_file(struct mount_info *mi, struct file *bf);
void incfs_free_data_file(struct data_file *df);
 
struct dir_file *incfs_open_dir_file(struct mount_info *mi, struct file *bf);
void incfs_free_dir_file(struct dir_file *dir);
 
struct incfs_read_data_file_timeouts {
<------>u32 min_time_us;
<------>u32 min_pending_time_us;
<------>u32 max_pending_time_us;
};
 
ssize_t incfs_read_data_file_block(struct mem_range dst, struct file *f,
<------><------><------>int index, struct mem_range tmp,
<------><------><------>struct incfs_read_data_file_timeouts *timeouts);
 
ssize_t incfs_read_merkle_tree_blocks(struct mem_range dst,
<------><------><------><------>      struct data_file *df, size_t offset);
 
int incfs_get_filled_blocks(struct data_file *df,
<------><------><------>    struct incfs_file_data *fd,
<------><------><------>    struct incfs_get_filled_blocks_args *arg);
 
int incfs_read_file_signature(struct data_file *df, struct mem_range dst);
 
int incfs_process_new_data_block(struct data_file *df,
<------><------><------><------> struct incfs_fill_block *block, u8 *data);
 
int incfs_process_new_hash_block(struct data_file *df,
<------><------><------><------> struct incfs_fill_block *block, u8 *data);
 
bool incfs_fresh_pending_reads_exist(struct mount_info *mi, int last_number);
 
/*
 * Collects pending reads and saves them into the array (reads/reads_size).
 * Only reads with serial_number > sn_lowerbound are reported.
 * Returns how many reads were saved into the array.
 */
int incfs_collect_pending_reads(struct mount_info *mi, int sn_lowerbound,
<------><------><------><------>struct incfs_pending_read_info *reads,
<------><------><------><------>struct incfs_pending_read_info2 *reads2,
<------><------><------><------>int reads_size, int *new_max_sn);
 
int incfs_collect_logged_reads(struct mount_info *mi,
<------><------><------>       struct read_log_state *start_state,
<------><------><------>       struct incfs_pending_read_info *reads,
<------><------><------>       struct incfs_pending_read_info2 *reads2,
<------><------><------>       int reads_size);
struct read_log_state incfs_get_log_state(struct mount_info *mi);
int incfs_get_uncollected_logs_count(struct mount_info *mi,
<------><------><------><------>     const struct read_log_state *state);
 
static inline struct inode_info *get_incfs_node(struct inode *inode)
{
<------>if (!inode)
<------><------>return NULL;
 
<------>if (inode->i_sb->s_magic != INCFS_MAGIC_NUMBER) {
<------><------>/* This inode doesn't belong to us. */
<------><------>pr_warn_once("incfs: %s on an alien inode.", __func__);
<------><------>return NULL;
<------>}
 
<------>return container_of(inode, struct inode_info, n_vfs_inode);
}
 
static inline struct data_file *get_incfs_data_file(struct file *f)
{
<------>struct inode_info *node = NULL;
 
<------>if (!f)
<------><------>return NULL;
 
<------>if (!S_ISREG(f->f_inode->i_mode))
<------><------>return NULL;
 
<------>node = get_incfs_node(f->f_inode);
<------>if (!node)
<------><------>return NULL;
 
<------>return node->n_file;
}
 
static inline struct dir_file *get_incfs_dir_file(struct file *f)
{
<------>if (!f)
<------><------>return NULL;
 
<------>if (!S_ISDIR(f->f_inode->i_mode))
<------><------>return NULL;
 
<------>return (struct dir_file *)f->private_data;
}
 
/*
 * Make sure that inode_info.n_file is initialized and inode can be used
 * for reading and writing data from/to the backing file.
 */
int make_inode_ready_for_data_ops(struct mount_info *mi,
<------><------><------><------>struct inode *inode,
<------><------><------><------>struct file *backing_file);
 
static inline struct dentry_info *get_incfs_dentry(const struct dentry *d)
{
<------>if (!d)
<------><------>return NULL;
 
<------>return (struct dentry_info *)d->d_fsdata;
}
 
static inline void get_incfs_backing_path(const struct dentry *d,
<------><------><------><------><------>  struct path *path)
{
<------>struct dentry_info *di = get_incfs_dentry(d);
 
<------>if (!di) {
<------><------>*path = (struct path) {};
<------><------>return;
<------>}
 
<------>*path = di->backing_path;
<------>path_get(path);
}
 
static inline int get_blocks_count_for_size(u64 size)
{
<------>if (size == 0)
<------><------>return 0;
<------>return 1 + (size - 1) / INCFS_DATA_FILE_BLOCK_SIZE;
}
 
#endif /* _INCFS_DATA_MGMT_H */