1 files changed, 84 insertions, 59 deletions

diff --git a/drivers/staging/lustre/lustre/include/lprocfs_status.h b/drivers/staging/lustre/lustre/include/lprocfs_status.h
index d68e60e7fef7..cc0713ef8ae5 100644
--- a/drivers/staging/lustre/lustre/include/lprocfs_status.h
+++ b/drivers/staging/lustre/lustre/include/lprocfs_status.h
@@ -165,8 +165,10 @@ struct lprocfs_percpu {
 	struct lprocfs_counter lp_cntr[0];
 };
 
-#define LPROCFS_GET_NUM_CPU 0x0001
-#define LPROCFS_GET_SMP_ID  0x0002
+enum lprocfs_stats_lock_ops {
+	LPROCFS_GET_NUM_CPU	= 0x0001, /* number allocated per-CPU stats */
+	LPROCFS_GET_SMP_ID	= 0x0002, /* current stat to be updated */
+};
 
 enum lprocfs_stats_flags {
 	LPROCFS_STATS_FLAG_NONE     = 0x0000, /* per cpu counter */
@@ -363,82 +365,99 @@ static inline void s2dhms(struct dhms *ts, time64_t secs64)
 #define JOBSTATS_PROCNAME_UID		"procname_uid"
 #define JOBSTATS_NODELOCAL		"nodelocal"
 
+/* obd_config.c */
+void lustre_register_client_process_config(int (*cpc)(struct lustre_cfg *lcfg));
+
 int lprocfs_write_frac_helper(const char __user *buffer,
 			      unsigned long count, int *val, int mult);
 int lprocfs_read_frac_helper(char *buffer, unsigned long count,
 			     long val, int mult);
 int lprocfs_stats_alloc_one(struct lprocfs_stats *stats, unsigned int cpuid);
-/*
- * \return value
- *      < 0     : on error (only possible for opc as LPROCFS_GET_SMP_ID)
+
+/**
+ * Lock statistics structure for access, possibly only on this CPU.
+ *
+ * The statistics struct may be allocated with per-CPU structures for
+ * efficient concurrent update (usually only on server-wide stats), or
+ * as a single global struct (e.g. for per-client or per-job statistics),
+ * so the required locking depends on the type of structure allocated.
+ *
+ * For per-CPU statistics, pin the thread to the current cpuid so that
+ * will only access the statistics for that CPU.  If the stats structure
+ * for the current CPU has not been allocated (or previously freed),
+ * allocate it now.  The per-CPU statistics do not need locking since
+ * the thread is pinned to the CPU during update.
+ *
+ * For global statistics, lock the stats structure to prevent concurrent update.
+ *
+ * \param[in] stats	statistics structure to lock
+ * \param[in] opc	type of operation:
+ *			LPROCFS_GET_SMP_ID: "lock" and return current CPU index
+ *				for incrementing statistics for that CPU
+ *			LPROCFS_GET_NUM_CPU: "lock" and return number of used
+ *				CPU indices to iterate over all indices
+ * \param[out] flags	CPU interrupt saved state for IRQ-safe locking
+ *
+ * \retval cpuid of current thread or number of allocated structs
+ * \retval negative on error (only for opc LPROCFS_GET_SMP_ID + per-CPU stats)
  */
-static inline int lprocfs_stats_lock(struct lprocfs_stats *stats, int opc,
+static inline int lprocfs_stats_lock(struct lprocfs_stats *stats,
+				     enum lprocfs_stats_lock_ops opc,
 				     unsigned long *flags)
 {
-	int		rc = 0;
+	if (stats->ls_flags & LPROCFS_STATS_FLAG_NOPERCPU) {
+		if (stats->ls_flags & LPROCFS_STATS_FLAG_IRQ_SAFE)
+			spin_lock_irqsave(&stats->ls_lock, *flags);
+		else
+			spin_lock(&stats->ls_lock);
+		return opc == LPROCFS_GET_NUM_CPU ? 1 : 0;
+	}
 
 	switch (opc) {
-	default:
-		LBUG();
+	case LPROCFS_GET_SMP_ID: {
+		unsigned int cpuid = get_cpu();
 
-	case LPROCFS_GET_SMP_ID:
-		if (stats->ls_flags & LPROCFS_STATS_FLAG_NOPERCPU) {
-			if (stats->ls_flags & LPROCFS_STATS_FLAG_IRQ_SAFE)
-				spin_lock_irqsave(&stats->ls_lock, *flags);
-			else
-				spin_lock(&stats->ls_lock);
-			return 0;
-		} else {
-			unsigned int cpuid = get_cpu();
-
-			if (unlikely(!stats->ls_percpu[cpuid])) {
-				rc = lprocfs_stats_alloc_one(stats, cpuid);
-				if (rc < 0) {
-					put_cpu();
-					return rc;
-				}
+		if (unlikely(!stats->ls_percpu[cpuid])) {
+			int rc = lprocfs_stats_alloc_one(stats, cpuid);
+
+			if (rc < 0) {
+				put_cpu();
+				return rc;
 			}
-			return cpuid;
 		}
-
+		return cpuid;
+	}
 	case LPROCFS_GET_NUM_CPU:
-		if (stats->ls_flags & LPROCFS_STATS_FLAG_NOPERCPU) {
-			if (stats->ls_flags & LPROCFS_STATS_FLAG_IRQ_SAFE)
-				spin_lock_irqsave(&stats->ls_lock, *flags);
-			else
-				spin_lock(&stats->ls_lock);
-			return 1;
-		}
 		return stats->ls_biggest_alloc_num;
+	default:
+		LBUG();
 	}
 }
 
-static inline void lprocfs_stats_unlock(struct lprocfs_stats *stats, int opc,
+/**
+ * Unlock statistics structure after access.
+ *
+ * Unlock the lock acquired via lprocfs_stats_lock() for global statistics,
+ * or unpin this thread from the current cpuid for per-CPU statistics.
+ *
+ * This function must be called using the same arguments as used when calling
+ * lprocfs_stats_lock() so that the correct operation can be performed.
+ *
+ * \param[in] stats	statistics structure to unlock
+ * \param[in] opc	type of operation (current cpuid or number of structs)
+ * \param[in] flags	CPU interrupt saved state for IRQ-safe locking
+ */
+static inline void lprocfs_stats_unlock(struct lprocfs_stats *stats,
+					enum lprocfs_stats_lock_ops opc,
 					unsigned long *flags)
 {
-	switch (opc) {
-	default:
-		LBUG();
-
-	case LPROCFS_GET_SMP_ID:
-		if (stats->ls_flags & LPROCFS_STATS_FLAG_NOPERCPU) {
-			if (stats->ls_flags & LPROCFS_STATS_FLAG_IRQ_SAFE)
-				spin_unlock_irqrestore(&stats->ls_lock, *flags);
-			else
-				spin_unlock(&stats->ls_lock);
-		} else {
-			put_cpu();
-		}
-		return;
-
-	case LPROCFS_GET_NUM_CPU:
-		if (stats->ls_flags & LPROCFS_STATS_FLAG_NOPERCPU) {
-			if (stats->ls_flags & LPROCFS_STATS_FLAG_IRQ_SAFE)
-				spin_unlock_irqrestore(&stats->ls_lock, *flags);
-			else
-				spin_unlock(&stats->ls_lock);
-		}
-		return;
+	if (stats->ls_flags & LPROCFS_STATS_FLAG_NOPERCPU) {
+		if (stats->ls_flags & LPROCFS_STATS_FLAG_IRQ_SAFE)
+			spin_unlock_irqrestore(&stats->ls_lock, *flags);
+		else
+			spin_unlock(&stats->ls_lock);
+	} else if (opc == LPROCFS_GET_SMP_ID) {
+		put_cpu();
 	}
 }
 
@@ -496,7 +515,7 @@ static inline __u64 lprocfs_stats_collector(struct lprocfs_stats *stats,
 					    int idx,
 					    enum lprocfs_fields_flags field)
 {
-	int	      i;
+	unsigned int i;
 	unsigned int  num_cpu;
 	unsigned long flags	= 0;
 	__u64	      ret	= 0;
@@ -681,6 +700,12 @@ static struct lustre_attr lustre_attr_##name = __ATTR(name, mode, show, store)
 
 extern const struct sysfs_ops lustre_sysfs_ops;
 
+struct root_squash_info;
+int lprocfs_wr_root_squash(const char *buffer, unsigned long count,
+			   struct root_squash_info *squash, char *name);
+int lprocfs_wr_nosquash_nids(const char *buffer, unsigned long count,
+			     struct root_squash_info *squash, char *name);
+
 /* all quota proc functions */
 int lprocfs_quota_rd_bunit(char *page, char **start,
 			   loff_t off, int count,