diff options
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/blkdev.h | 1 | ||||
| -rw-r--r-- | include/linux/fs.h | 26 | ||||
| -rw-r--r-- | include/linux/pagemap.h | 43 | ||||
| -rw-r--r-- | include/linux/sched/task.h | 6 |
4 files changed, 70 insertions, 6 deletions
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 9ab06ea26894..06ecb2c1492f 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1180,6 +1180,7 @@ struct blk_plug { struct list_head cb_list; /* md requires an unplug callback */ unsigned short rq_count; bool multiple_queues; + bool nowait; }; #define BLK_MAX_REQUEST_COUNT 16 #define BLK_PLUG_FLUSH_SIZE (128 * 1024) diff --git a/include/linux/fs.h b/include/linux/fs.h index cdfed8c99750..bd7ec3eaeed0 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -175,6 +175,9 @@ typedef int (dio_iodone_t)(struct kiocb *iocb, loff_t offset, /* File does not contribute to nr_files count */ #define FMODE_NOACCOUNT ((__force fmode_t)0x20000000) +/* File supports async buffered reads */ +#define FMODE_BUF_RASYNC ((__force fmode_t)0x40000000) + /* * Flag for rw_copy_check_uvector and compat_rw_copy_check_uvector * that indicates that they should check the contents of the iovec are @@ -315,6 +318,8 @@ enum rw_hint { #define IOCB_SYNC (1 << 5) #define IOCB_WRITE (1 << 6) #define IOCB_NOWAIT (1 << 7) +/* iocb->ki_waitq is valid */ +#define IOCB_WAITQ (1 << 8) #define IOCB_NOIO (1 << 9) struct kiocb { @@ -329,7 +334,10 @@ struct kiocb { int ki_flags; u16 ki_hint; u16 ki_ioprio; /* See linux/ioprio.h */ - unsigned int ki_cookie; /* for ->iopoll */ + union { + unsigned int ki_cookie; /* for ->iopoll */ + struct wait_page_queue *ki_waitq; /* for async buffered IO */ + }; randomized_struct_fields_end }; @@ -3275,22 +3283,28 @@ static inline int iocb_flags(struct file *file) static inline int kiocb_set_rw_flags(struct kiocb *ki, rwf_t flags) { + int kiocb_flags = 0; + + if (!flags) + return 0; if (unlikely(flags & ~RWF_SUPPORTED)) return -EOPNOTSUPP; if (flags & RWF_NOWAIT) { if (!(ki->ki_filp->f_mode & FMODE_NOWAIT)) return -EOPNOTSUPP; - ki->ki_flags |= IOCB_NOWAIT; + kiocb_flags |= IOCB_NOWAIT; } if (flags & RWF_HIPRI) - ki->ki_flags |= IOCB_HIPRI; + kiocb_flags |= IOCB_HIPRI; if (flags & RWF_DSYNC) - ki->ki_flags |= IOCB_DSYNC; + kiocb_flags |= IOCB_DSYNC; if (flags & RWF_SYNC) - ki->ki_flags |= (IOCB_DSYNC | IOCB_SYNC); + kiocb_flags |= (IOCB_DSYNC | IOCB_SYNC); if (flags & RWF_APPEND) - ki->ki_flags |= IOCB_APPEND; + kiocb_flags |= IOCB_APPEND; + + ki->ki_flags |= kiocb_flags; return 0; } diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index cf2468da68e9..d1f4eff605ad 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -496,8 +496,35 @@ static inline pgoff_t linear_page_index(struct vm_area_struct *vma, return pgoff; } +/* This has the same layout as wait_bit_key - see fs/cachefiles/rdwr.c */ +struct wait_page_key { + struct page *page; + int bit_nr; + int page_match; +}; + +struct wait_page_queue { + struct page *page; + int bit_nr; + wait_queue_entry_t wait; +}; + +static inline bool wake_page_match(struct wait_page_queue *wait_page, + struct wait_page_key *key) +{ + if (wait_page->page != key->page) + return false; + key->page_match = 1; + + if (wait_page->bit_nr != key->bit_nr) + return false; + + return true; +} + extern void __lock_page(struct page *page); extern int __lock_page_killable(struct page *page); +extern int __lock_page_async(struct page *page, struct wait_page_queue *wait); extern int __lock_page_or_retry(struct page *page, struct mm_struct *mm, unsigned int flags); extern void unlock_page(struct page *page); @@ -535,6 +562,22 @@ static inline int lock_page_killable(struct page *page) } /* + * lock_page_async - Lock the page, unless this would block. If the page + * is already locked, then queue a callback when the page becomes unlocked. + * This callback can then retry the operation. + * + * Returns 0 if the page is locked successfully, or -EIOCBQUEUED if the page + * was already locked and the callback defined in 'wait' was queued. + */ +static inline int lock_page_async(struct page *page, + struct wait_page_queue *wait) +{ + if (!trylock_page(page)) + return __lock_page_async(page, wait); + return 0; +} + +/* * lock_page_or_retry - Lock the page, unless this would block and the * caller indicated that it can handle a retry. * diff --git a/include/linux/sched/task.h b/include/linux/sched/task.h index 38359071236a..1301077f9c24 100644 --- a/include/linux/sched/task.h +++ b/include/linux/sched/task.h @@ -126,6 +126,12 @@ static inline void put_task_struct(struct task_struct *t) __put_task_struct(t); } +static inline void put_task_struct_many(struct task_struct *t, int nr) +{ + if (refcount_sub_and_test(nr, &t->usage)) + __put_task_struct(t); +} + void put_task_struct_rcu_user(struct task_struct *task); #ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT |