[mirror_ubuntu-bionic-kernel.git] / include / linux / shm.h

#ifndef _LINUX_SHM_H_
#define _LINUX_SHM_H_

#include <linux/list.h>
#include <asm/page.h>
#include <uapi/linux/shm.h>
#include <asm/shmparam.h>

struct shmid_kernel /* private to the kernel */
{	
	struct kern_ipc_perm	shm_perm;
	struct file		*shm_file;
	unsigned long		shm_nattch;
	unsigned long		shm_segsz;
	time_t			shm_atim;
	time_t			shm_dtim;
	time_t			shm_ctim;
	pid_t			shm_cprid;
	pid_t			shm_lprid;
	struct user_struct	*mlock_user;

	/* The task created the shm object.  NULL if the task is dead. */
	struct task_struct	*shm_creator;
	struct list_head	shm_clist;	/* list by creator */
};

/* shm_mode upper byte flags */
#define	SHM_DEST	01000	/* segment will be destroyed on last detach */
#define SHM_LOCKED      02000   /* segment will not be swapped */
#define SHM_HUGETLB     04000   /* segment will use huge TLB pages */
#define SHM_NORESERVE   010000  /* don't check for reservations */

/* Bits [26:31] are reserved */

/*
 * When SHM_HUGETLB is set bits [26:31] encode the log2 of the huge page size.
 * This gives us 6 bits, which is enough until someone invents 128 bit address
 * spaces.
 *
 * Assume these are all power of twos.
 * When 0 use the default page size.
 */
#define SHM_HUGE_SHIFT  26
#define SHM_HUGE_MASK   0x3f
#define SHM_HUGE_2MB    (21 << SHM_HUGE_SHIFT)
#define SHM_HUGE_1GB    (30 << SHM_HUGE_SHIFT)

#ifdef CONFIG_SYSVIPC
struct sysv_shm {
	struct list_head shm_clist;
};

long do_shmat(int shmid, char __user *shmaddr, int shmflg, unsigned long *addr,
	      unsigned long shmlba);
int is_file_shm_hugepages(struct file *file);
void exit_shm(struct task_struct *task);
#define shm_init_task(task) INIT_LIST_HEAD(&(task)->sysvshm.shm_clist)
#else
struct sysv_shm {
	/* empty */
};

static inline long do_shmat(int shmid, char __user *shmaddr,
			    int shmflg, unsigned long *addr,
			    unsigned long shmlba)
{
	return -ENOSYS;
}
static inline int is_file_shm_hugepages(struct file *file)
{
	return 0;
}
static inline void exit_shm(struct task_struct *task)
{
}
static inline void shm_init_task(struct task_struct *task)
{
}
#endif

#endif /* _LINUX_SHM_H_ */
Commit	Line	Data
1da177e4 LT	1	#ifndef _LINUX_SHM_H_
	2	#define _LINUX_SHM_H_
	3
ab602f79	4	#include <linux/list.h>
1da177e4	5	#include <asm/page.h>
607ca46e	6	#include <uapi/linux/shm.h>
1da177e4	7	#include <asm/shmparam.h>
060028ba	8
1da177e4 LT	9	struct shmid_kernel /* private to the kernel */
	10	{
	11	struct kern_ipc_perm shm_perm;
239521f3	12	struct file *shm_file;
1da177e4 LT	13	unsigned long shm_nattch;
	14	unsigned long shm_segsz;
	15	time_t shm_atim;
	16	time_t shm_dtim;
	17	time_t shm_ctim;
	18	pid_t shm_cprid;
	19	pid_t shm_lprid;
	20	struct user_struct *mlock_user;
5774ed01 VK	21
	22	/* The task created the shm object. NULL if the task is dead. */
	23	struct task_struct *shm_creator;
ab602f79	24	struct list_head shm_clist; /* list by creator */
1da177e4 LT	25	};
	26
	27	/* shm_mode upper byte flags */
	28	#define SHM_DEST 01000 /* segment will be destroyed on last detach */
	29	#define SHM_LOCKED 02000 /* segment will not be swapped */
	30	#define SHM_HUGETLB 04000 /* segment will use huge TLB pages */
bf8f972d	31	#define SHM_NORESERVE 010000 /* don't check for reservations */
1da177e4	32
42d7395f AK	33	/* Bits [26:31] are reserved */
	34
	35	/*
	36	* When SHM_HUGETLB is set bits [26:31] encode the log2 of the huge page size.
	37	* This gives us 6 bits, which is enough until someone invents 128 bit address
	38	* spaces.
	39	*
	40	* Assume these are all power of twos.
	41	* When 0 use the default page size.
	42	*/
	43	#define SHM_HUGE_SHIFT 26
	44	#define SHM_HUGE_MASK 0x3f
	45	#define SHM_HUGE_2MB (21 << SHM_HUGE_SHIFT)
	46	#define SHM_HUGE_1GB (30 << SHM_HUGE_SHIFT)
	47
1da177e4	48	#ifdef CONFIG_SYSVIPC
ab602f79 JM	49	struct sysv_shm {
	50	struct list_head shm_clist;
	51	};
	52
079a96ae WD	53	long do_shmat(int shmid, char __user shmaddr, int shmflg, unsigned long addr,
079a96ae WD	54	unsigned long shmlba);
2f137d66	55	int is_file_shm_hugepages(struct file *file);
ab602f79 JM	56	void exit_shm(struct task_struct *task);
ab602f79 JM	57	#define shm_init_task(task) INIT_LIST_HEAD(&(task)->sysvshm.shm_clist)
1da177e4	58	#else
ab602f79 JM	59	struct sysv_shm {
	60	/* empty */
	61	};
	62
1da177e4	63	static inline long do_shmat(int shmid, char __user *shmaddr,
079a96ae WD	64	int shmflg, unsigned long *addr,
079a96ae WD	65	unsigned long shmlba)
1da177e4 LT	66	{
	67	return -ENOSYS;
	68	}
516dffdc AL	69	static inline int is_file_shm_hugepages(struct file *file)
	70	{
	71	return 0;
	72	}
b34a6b1d VK	73	static inline void exit_shm(struct task_struct *task)
	74	{
	75	}
ab602f79 JM	76	static inline void shm_init_task(struct task_struct *task)
	77	{
	78	}
1da177e4 LT	79	#endif
1da177e4 LT	80
1da177e4	81	#endif /* _LINUX_SHM_H_ */