LDD和scull相关各种结构体的故事(学习笔记 不定期更新)
LDD和各种结构体的故事
struct scull_dev 位置：scull/scull.h
struct scull_dev {
struct scull_qset *data; /* Pointer to first quantum set */
int quantum; /* the current quantum size */
int qset; /* the current array size */
unsigned long size; /* amount of data stored here */
unsigned int access_key; /* used by sculluid and scullpriv */
struct mutex mutex; /* mutual exclusion semaphore */
struct cdev cdev; /* Char device structure */
};
struct mutex 位置：/usr/src/linux-source/include/linux/
struct mutex {
/* 1: unlocked, 0: locked, negative: locked, possible waiters */
atomic_t count;
spinlock_t wait_lock;
struct list_head wait_list;
#if defined(CONFIG_DEBUG_MUTEXES) || defined(CONFIG_SMP)
struct task_struct *owner;
#endif
#ifdef CONFIG_DEBUG_MUTEXES
const char *name;
void *magic;
#endif
#ifdef CONFIG_DEBUG_LOCK_ALLOC
struct lockdep_map dep_map;
#endif
};
这个有点点长哇。。。
struct inode 位置：/usr/src/linux-source/include/linux/fs.h
/*
* Keep mostly read-only and often accessed (especially for
* the RCU path lookup and 'stat' data) fields at the beginning
* of the 'struct inode'
*/
struct inode {
umode_t i_mode;
unsigned short i_opflags;
kuid_t i_uid;
kgid_t i_gid;
unsigned int i_flags;
#ifdef CONFIG_FS_POSIX_ACL
struct posix_acl *i_acl;
struct posix_acl *i_default_acl;
#endif
const struct inode_operations *i_op;
struct super_block *i_sb;
struct address_space *i_mapping;
#ifdef CONFIG_SECURITY
void *i_security;
#endif
/* Stat data, not accessed from path walking */
unsigned long i_ino;
/*
* Filesystems may only read i_nlink directly. They shall use the
* following functions for modification:
*
* (set|clear|inc|drop)_nlink
* inode_(inc|dec)_link_count
*/
union {
const unsigned int i_nlink;
unsigned int __i_nlink;
};
dev_t i_rdev;
loff_t i_size;
struct timespec i_atime;
struct timespec i_mtime;
struct timespec i_ctime;
spinlock_t i_lock; /* i_blocks, i_bytes, maybe i_size */
unsigned short i_bytes;
unsigned int i_blkbits;
blkcnt_t i_blocks;
#ifdef __NEED_I_SIZE_ORDERED
seqcount_t i_size_seqcount;
#endif
/* Misc */
unsigned long i_state;
struct mutex i_mutex;
unsigned long dirtied_when; /* jiffies of first dirtying */
struct hlist_node i_hash;
struct list_head i_wb_list; /* backing dev IO list */
struct list_head i_lru; /* inode LRU list */
struct list_head i_sb_list;
union {
struct hlist_head i_dentry;
struct rcu_head i_rcu;
};
u64 i_version;
atomic_t i_count;
atomic_t i_dio_count;
atomic_t i_writecount;
const struct file_operations *i_fop; /* former ->i_op->default_file_ops */
struct file_lock *i_flock;
struct address_space i_data;
#ifdef CONFIG_QUOTA
struct dquot *i_dquot[MAXQUOTAS];
#endif
struct list_head i_devices;
union {
struct pipe_inode_info *i_pipe;
struct block_device *i_bdev;
struct cdev *i_cdev;
};
__u32 i_generation;
#ifdef CONFIG_FSNOTIFY
__u32 i_fsnotify_mask; /* all events this inode cares about */
struct hlist_head i_fsnotify_marks;
#endif
#ifdef CONFIG_IMA
atomic_t i_readcount; /* struct files open RO */
#endif
void *i_private; /* fs or device private pointer */
};
struct file 位置：/usr/src/linux-source/include/linux/fs.h
struct file {
/*
* fu_list becomes invalid after file_free is called and queued via
* fu_rcuhead for RCU freeing
*/
union {
struct list_head fu_list;
struct rcu_head fu_rcuhead;
} f_u;
struct path f_path;
#define f_dentry f_path.dentry
#define f_vfsmnt f_path.mnt
const struct file_operations *f_op;
/*
* Protects f_ep_links, f_flags, f_pos vs i_size in lseek SEEK_CUR.
* Must not be taken from IRQ context.
*/
spinlock_t f_lock;
#ifdef CONFIG_SMP
int f_sb_list_cpu;
#endif
atomic_long_t f_count;
unsigned int f_flags;
fmode_t f_mode;
loff_t f_pos;
struct fown_struct f_owner;
const struct cred *f_cred;
struct file_ra_state f_ra;
u64 f_version;
#ifdef CONFIG_SECURITY
void *f_security;
#endif
/* needed for tty driver, and maybe others */
void *private_data;
#ifdef CONFIG_EPOLL
/* Used by fs/eventpoll.c to link all the hooks to this file */
struct list_head f_ep_links;
struct list_head f_tfile_llink;
#endif /* #ifdef CONFIG_EPOLL */
struct address_space *f_mapping;
#ifdef CONFIG_DEBUG_WRITECOUNT
unsigned long f_mnt_write_state;
#endif
};
struct cdev 位置：/usr/src/linux-source/include/linux/cdev.h
struct cdev {
struct kobject kobj;
struct module *owner;
const struct file_operations *ops;
struct list_head list;
dev_t dev;
unsigned int count;
};
struct scull_qset 位置：scull/scull.h
struct scull_qset {
void **data;
struct scull_qset *next;
};
struct seq_file 位置：/usr/src/linux-source/include/linux/sqe_file.h
struct seq_file {
char *buf;
size_t size;
size_t from;
size_t count;
loff_t index;
loff_t read_pos;
u64 version;
struct mutex lock;
const struct seq_operations *op;
int poll_event;
#ifdef CONFIG_USER_NS
struct user_namespace *user_ns;
#endif
void *private;
};
kmem_cache
位置：/usr/src/linux-source/include/linux/slab.h
struct kmem_cache {
unsigned int object_size;/* The original size of the object */
unsigned int size; /* The aligned/padded/added on size */
unsigned int align; /* Alignment as calculated */
unsigned long flags; /* Active flags on the slab */
const char *name; /* Slab name for sysfs */
int refcount; /* Use counter */
void (*ctor)(void *); /* Called on object slot creation */
struct list_head list; /* List of all slab caches on the system */
};
poll_table
位置：/usr/src/linux-source/include/linux/poll.h
typedef struct poll_table_struct {
poll_queue_proc _qproc;
unsigned long _key;
} poll_table;
work_struct
位置：/usr/src/linux-source/include/linux/workqueue.h
struct work_struct {
atomic_long_t data;
struct list_head entry;
work_func_t func;
#ifdef CONFIG_LOCKDEP
struct lockdep_map lockdep_map;
#endif
};
"也哭也笑，平凡着"
—— 平凡之路
