staging/lustre/llite: move llite/max_read_ahead_whole_mb to sysfs

Move max_read_ahead_whole_mb file from /proc/fs/lustre/llite/*
to /sys/fs/lustre/llite/*/
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/llite/lproc_llite.c

@@ -312,10 +312,12 @@ static ssize_t max_read_ahead_per_file_mb_store(struct kobject *kobj,
 }
 LUSTRE_RW_ATTR(max_read_ahead_per_file_mb);
 
-static int ll_max_read_ahead_whole_mb_seq_show(struct seq_file *m, void *unused)
+static ssize_t max_read_ahead_whole_mb_show(struct kobject *kobj,
+					    struct attribute *attr,
+					    char *buf)
 {
-	struct super_block *sb = m->private;
-	struct ll_sb_info *sbi = ll_s2sbi(sb);
+	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
+					      ll_kobj);
 	long pages_number;
 	int mult;
 
@@ -324,26 +326,26 @@ static int ll_max_read_ahead_whole_mb_seq_show(struct seq_file *m, void *unused)
 	spin_unlock(&sbi->ll_lock);
 
 	mult = 1 << (20 - PAGE_CACHE_SHIFT);
-	return lprocfs_seq_read_frac_helper(m, pages_number, mult);
+	return lprocfs_read_frac_helper(buf, PAGE_SIZE, pages_number, mult);
 }
 
-static ssize_t ll_max_read_ahead_whole_mb_seq_write(struct file *file,
-						const char __user *buffer,
-						size_t count, loff_t *off)
+static ssize_t max_read_ahead_whole_mb_store(struct kobject *kobj,
+					     struct attribute *attr,
+					     const char  *buffer,
+					     size_t count)
 {
-	struct super_block *sb = ((struct seq_file *)file->private_data)->private;
-	struct ll_sb_info *sbi = ll_s2sbi(sb);
-	int mult, rc, pages_number;
+	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
+					      ll_kobj);
+	int rc;
+	unsigned long pages_number;
 
-	mult = 1 << (20 - PAGE_CACHE_SHIFT);
-	rc = lprocfs_write_frac_helper(buffer, count, &pages_number, mult);
+	rc = kstrtoul(buffer, 10, &pages_number);
 	if (rc)
 		return rc;
 
 	/* Cap this at the current max readahead window size, the readahead
 	 * algorithm does this anyway so it's pointless to set it larger. */
-	if (pages_number < 0 ||
-	    pages_number > sbi->ll_ra_info.ra_max_pages_per_file) {
+	if (pages_number > sbi->ll_ra_info.ra_max_pages_per_file) {
 		CERROR("can't set max_read_ahead_whole_mb more than max_read_ahead_per_file_mb: %lu\n",
 		       sbi->ll_ra_info.ra_max_pages_per_file >> (20 - PAGE_CACHE_SHIFT));
 		return -ERANGE;
@@ -355,7 +357,7 @@ static ssize_t ll_max_read_ahead_whole_mb_seq_write(struct file *file,
 
 	return count;
 }
-LPROC_SEQ_FOPS(ll_max_read_ahead_whole_mb);
+LUSTRE_RW_ATTR(max_read_ahead_whole_mb);
 
 static int ll_max_cached_mb_seq_show(struct seq_file *m, void *v)
 {
@@ -847,7 +849,6 @@ static struct lprocfs_vars lprocfs_llite_obd_vars[] = {
 	/* { "mntpt_path",   ll_rd_path,	     0, 0 }, */
 	{ "site",	  &ll_site_stats_fops,    NULL, 0 },
 	/* { "filegroups",   lprocfs_rd_filegroups,  0, 0 }, */
-	{ "max_read_ahead_whole_mb", &ll_max_read_ahead_whole_mb_fops, NULL },
 	{ "max_cached_mb",    &ll_max_cached_mb_fops, NULL },
 	{ "checksum_pages",   &ll_checksum_fops, NULL },
 	{ "max_rw_chunk",     &ll_max_rw_chunk_fops, NULL },
@@ -881,6 +882,7 @@ static struct attribute *llite_attrs[] = {
 	&lustre_attr_uuid.attr,
 	&lustre_attr_max_read_ahead_mb.attr,
 	&lustre_attr_max_read_ahead_per_file_mb.attr,
+	&lustre_attr_max_read_ahead_whole_mb.attr,
 	NULL,
 };
 

drivers/staging/lustre/sysfs-fs-lustre

@@ -110,3 +110,10 @@ Date:		May 2015
 Contact:	"Oleg Drokin" <oleg.drokin@intel.com>
 Description:
 		Sets maximum number of megabytes to read-ahead for a single file
+
+What:		/sys/fs/lustre/llite/<fsname>-<uuid>/max_read_ahead_whole_mb
+Date:		May 2015
+Contact:	"Oleg Drokin" <oleg.drokin@intel.com>
+Description:
+		For small reads, how many megabytes to actually request from
+		the server as initial read-ahead.