diff options
Diffstat (limited to 'kernel/include/linux/shm.h')
-rw-r--r-- | kernel/include/linux/shm.h | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/kernel/include/linux/shm.h b/kernel/include/linux/shm.h new file mode 100644 index 000000000..6fb801686 --- /dev/null +++ b/kernel/include/linux/shm.h @@ -0,0 +1,81 @@ +#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_ */ |