Linux 4.18 compat: inode timespec -> timespec64

Commit torvalds/linux@95582b0 changes the inode i_atime, i_mtime,
and i_ctime members form timespec's to timespec64's to make them
2038 safe.  As part of this change the current_time() function was
also updated to return the timespec64 type.

Resolve this issue by introducing a new inode_timespec_t type which
is defined to match the timespec type used by the inode.  It should
be used when working with inode timestamps to ensure matching types.

The timestruc_t type under Illumos was used in a similar fashion but
was specified to always be a timespec_t.  Rather than incorrectly
define this type all timespec_t types have been replaced by the new
inode_timespec_t type.

Finally, the kernel and user space 'sys/time.h' headers were aligned
with each other.  They define as appropriate for the context several
constants as macros and include static inline implementation of
gethrestime(), gethrestime_sec(), and gethrtime().

Reviewed-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #7643

include/spl/sys/condvar.h

@@ -30,6 +30,7 @@
 #include <sys/mutex.h>
 #include <sys/callo.h>
 #include <sys/wait.h>
+#include <sys/time.h>
 
 /*
  * The kcondvar_t struct is protected by mutex taken externally before

include/spl/sys/time.h

@@ -54,13 +54,26 @@
 
 static const int hz = HZ;
 
+typedef longlong_t		hrtime_t;
+typedef struct timespec		timespec_t;
+
 #define	TIMESPEC_OVERFLOW(ts)		\
 	((ts)->tv_sec < TIME_MIN || (ts)->tv_sec > TIME_MAX)
 
+#if defined(HAVE_INODE_TIMESPEC64_TIMES)
+typedef struct timespec64	inode_timespec_t;
+#else
+typedef struct timespec		inode_timespec_t;
+#endif
+
 static inline void
-gethrestime(timestruc_t *now)
+gethrestime(inode_timespec_t *ts)
 {
-	*now = current_kernel_time();
+#if defined(HAVE_INODE_TIMESPEC64_TIMES)
+	*ts = current_kernel_time64();
+#else
+	*ts = current_kernel_time();
+#endif
 }
 
 static inline time_t
@@ -74,9 +87,9 @@ gethrestime_sec(void)
 static inline hrtime_t
 gethrtime(void)
 {
-	struct timespec now;
-	getrawmonotonic(&now);
-	return (((hrtime_t)now.tv_sec * NSEC_PER_SEC) + now.tv_nsec);
+	struct timespec ts;
+	getrawmonotonic(&ts);
+	return (((hrtime_t)ts.tv_sec * NSEC_PER_SEC) + ts.tv_nsec);
 }
 
 #endif  /* _SPL_TIME_H */

include/spl/sys/types.h

@@ -53,10 +53,6 @@ typedef unsigned long long	rlim64_t;
 typedef struct task_struct	kthread_t;
 typedef struct task_struct	proc_t;
 
-typedef struct timespec		timestruc_t;
-typedef struct timespec		timespec_t;
-typedef longlong_t		hrtime_t;
-
 typedef int			id_t;
 typedef short			pri_t;
 typedef short			index_t;

include/spl/sys/vnode.h

@@ -128,9 +128,9 @@ typedef struct vattr {
 	long		va_nodeid;	/* node # */
 	uint32_t	va_nlink;	/* # links */
 	uint64_t	va_size;	/* file size */
-	struct timespec	va_atime;	/* last acc */
-	struct timespec	va_mtime;	/* last mod */
-	struct timespec	va_ctime;	/* last chg */
+	inode_timespec_t va_atime;	/* last acc */
+	inode_timespec_t va_mtime;	/* last mod */
+	inode_timespec_t va_ctime;	/* last chg */
 	dev_t		va_rdev;	/* dev */
 	uint64_t	va_nblocks;	/* space used */
 	uint32_t	va_blksize;	/* block size */

include/sys/dmu.h

@@ -962,7 +962,7 @@ uint64_t dmu_objset_fsid_guid(objset_t *os);
 /*
  * Get the [cm]time for an objset's snapshot dir
  */
-timestruc_t dmu_objset_snap_cmtime(objset_t *os);
+inode_timespec_t dmu_objset_snap_cmtime(objset_t *os);
 
 int dmu_objset_is_snapshot(objset_t *os);
 

include/sys/dmu_objset.h

@@ -211,7 +211,7 @@ int dmu_objset_find_dp(struct dsl_pool *dp, uint64_t ddobj,
     int func(struct dsl_pool *, struct dsl_dataset *, void *),
     void *arg, int flags);
 void dmu_objset_evict_dbufs(objset_t *os);
-timestruc_t dmu_objset_snap_cmtime(objset_t *os);
+inode_timespec_t dmu_objset_snap_cmtime(objset_t *os);
 
 /* called from dsl */
 void dmu_objset_sync(objset_t *os, zio_t *zio, dmu_tx_t *tx);

include/sys/dsl_dir.h

@@ -108,7 +108,7 @@ struct dsl_dir {
 	/* Protected by dd_lock */
 	kmutex_t dd_lock;
 	list_t dd_props; /* list of dsl_prop_record_t's */
-	timestruc_t dd_snap_cmtime; /* last time snapshot namespace changed */
+	inode_timespec_t dd_snap_cmtime; /* last snapshot namespace change */
 	uint64_t dd_origin_txg;
 
 	/* gross estimate of space used by in-flight tx's */
@@ -180,7 +180,7 @@ boolean_t dsl_dir_is_clone(dsl_dir_t *dd);
 void dsl_dir_new_refreservation(dsl_dir_t *dd, struct dsl_dataset *ds,
     uint64_t reservation, cred_t *cr, dmu_tx_t *tx);
 void dsl_dir_snap_cmtime_update(dsl_dir_t *dd);
-timestruc_t dsl_dir_snap_cmtime(dsl_dir_t *dd);
+inode_timespec_t dsl_dir_snap_cmtime(dsl_dir_t *dd);
 void dsl_dir_set_reservation_sync_impl(dsl_dir_t *dd, uint64_t value,
     dmu_tx_t *tx);
 void dsl_dir_zapify(dsl_dir_t *dd, dmu_tx_t *tx);

include/sys/spa_impl.h

@@ -224,7 +224,7 @@ struct spa {
 	uint64_t	spa_freeze_txg;		/* freeze pool at this txg */
 	uint64_t	spa_load_max_txg;	/* best initial ub_txg */
 	uint64_t	spa_claim_max_txg;	/* highest claimed birth txg */
-	timespec_t	spa_loaded_ts;		/* 1st successful open time */
+	inode_timespec_t spa_loaded_ts;		/* 1st successful open time */
 	objset_t	*spa_meta_objset;	/* copy of dp->dp_meta_objset */
 	kmutex_t	spa_evicting_os_lock;	/* Evicting objset list lock */
 	list_t		spa_evicting_os_list;	/* Objsets being evicted. */

include/sys/xvattr.h

@@ -48,7 +48,7 @@
  * Structure of all optional attributes.
  */
 typedef struct xoptattr {
-	timestruc_t	xoa_createtime;	/* Create time of file */
+	inode_timespec_t xoa_createtime;	/* Create time of file */
 	uint8_t		xoa_archive;
 	uint8_t		xoa_system;
 	uint8_t		xoa_readonly;

include/sys/zfs_context.h

@@ -483,7 +483,7 @@ extern char *vn_dumpdir;
 #define	AV_SCANSTAMP_SZ	32		/* length of anti-virus scanstamp */
 
 typedef struct xoptattr {
-	timestruc_t	xoa_createtime;	/* Create time of file */
+	inode_timespec_t xoa_createtime;	/* Create time of file */
 	uint8_t		xoa_archive;
 	uint8_t		xoa_system;
 	uint8_t		xoa_readonly;
@@ -596,13 +596,6 @@ extern void delay(clock_t ticks);
 #define	USEC_TO_TICK(usec)	((usec) / (MICROSEC / hz))
 #define	NSEC_TO_TICK(usec)	((usec) / (NANOSEC / hz))
 
-#define	gethrestime_sec() time(NULL)
-#define	gethrestime(t) \
-	do {\
-		(t)->tv_sec = gethrestime_sec();\
-		(t)->tv_nsec = 0;\
-	} while (0);
-
 #define	max_ncpus	64
 #define	boot_ncpus	(sysconf(_SC_NPROCESSORS_ONLN))
 

include/sys/zfs_znode.h

@@ -291,19 +291,36 @@ zfs_inherit_projid(znode_t *dzp)
 
 extern unsigned int zfs_object_mutex_size;
 
-/* Encode ZFS stored time values from a struct timespec */
+/*
+ * Encode ZFS stored time values from a struct timespec / struct timespec64.
+ */
 #define	ZFS_TIME_ENCODE(tp, stmp)		\
-{						\
+do {						\
 	(stmp)[0] = (uint64_t)(tp)->tv_sec;	\
 	(stmp)[1] = (uint64_t)(tp)->tv_nsec;	\
-}
+} while (0)
 
-/* Decode ZFS stored time values to a struct timespec */
+#if defined(HAVE_INODE_TIMESPEC64_TIMES)
+/*
+ * Decode ZFS stored time values to a struct timespec64
+ * 4.18 and newer kernels.
+ */
 #define	ZFS_TIME_DECODE(tp, stmp)		\
-{						\
-	(tp)->tv_sec = (time_t)(stmp)[0];		\
-	(tp)->tv_nsec = (long)(stmp)[1];		\
-}
+do {						\
+	(tp)->tv_sec = (time64_t)(stmp)[0];	\
+	(tp)->tv_nsec = (long)(stmp)[1];	\
+} while (0)
+#else
+/*
+ * Decode ZFS stored time values to a struct timespec
+ * 4.17 and older kernels.
+ */
+#define	ZFS_TIME_DECODE(tp, stmp)		\
+do {						\
+	(tp)->tv_sec = (time_t)(stmp)[0];	\
+	(tp)->tv_nsec = (long)(stmp)[1];	\
+} while (0)
+#endif /* HAVE_INODE_TIMESPEC64_TIMES */
 
 /*
  * Timestamp defines

include/sys/zpl.h

@@ -188,4 +188,13 @@ zpl_dir_emit_dots(struct file *file, zpl_dir_context_t *ctx)
 }
 #endif /* HAVE_VFS_ITERATE */
 
+/*
+ * Linux 4.18, inode times converted from timespec to timespec64.
+ */
+#if defined(HAVE_INODE_TIMESPEC64_TIMES)
+#define	zpl_inode_timespec_trunc(ts, gran)	timespec64_trunc(ts, gran)
+#else
+#define	zpl_inode_timespec_trunc(ts, gran)	timespec_trunc(ts, gran)
+#endif
+
 #endif	/* _SYS_ZPL_H */