[PATCH v5 02/15] btrfs-progs: introduce raid parameters variables

From: Naohiro Aota <naohiro.aota@wdc.com>
To: linux-btrfs@vger.kernel.org, David Sterba <dsterba@suse.com>
Cc: Chris Mason <clm@fb.com>, Josef Bacik <josef@toxicpanda.com>,
	Nikolay Borisov <nborisov@suse.com>,
	Damien Le Moal <damien.lemoal@wdc.com>,
	Johannes Thumshirn <jthumshirn@suse.de>,
	Hannes Reinecke <hare@suse.com>,
	Anand Jain <anand.jain@oracle.com>,
	linux-fsdevel@vger.kernel.org,
	Naohiro Aota <naohiro.aota@wdc.com>
Subject: [PATCH v5 02/15] btrfs-progs: introduce raid parameters variables
Date: Wed,  4 Dec 2019 17:25:00 +0900	[thread overview]
Message-ID: <20191204082513.857320-3-naohiro.aota@wdc.com> (raw)
In-Reply-To: <20191204082513.857320-1-naohiro.aota@wdc.com>

Userland btrfs_alloc_chunk() and its kernel side counterpart
__btrfs_alloc_chunk() is so diverged that it's difficult to use the kernel
code as is.

This commit introduces some RAID parameter variables and read them from
btrfs_raid_array as the same as in kernel land.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 volumes.c | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/volumes.c b/volumes.c
index 143164f02ac0..8bfffa5586eb 100644
--- a/volumes.c
+++ b/volumes.c
@@ -1014,6 +1014,18 @@ int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 	int max_stripes = 0;
 	int min_stripes = 1;
 	int sub_stripes = 1;
+	int dev_stripes __attribute__((unused));
+				/* stripes per dev */
+	int devs_max;		/* max devs to use */
+	int devs_min __attribute__((unused));
+				/* min devs needed */
+	int devs_increment __attribute__((unused));
+				/* ndevs has to be a multiple of this */
+	int ncopies __attribute__((unused));
+				/* how many copies to data has */
+	int nparity __attribute__((unused));
+				/* number of stripes worth of bytes to
+				   store parity information */
 	int looped = 0;
 	int ret;
 	int index;
@@ -1025,6 +1037,18 @@ int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 		return -ENOSPC;
 	}
 
+	index = btrfs_bg_flags_to_raid_index(type);
+
+	sub_stripes = btrfs_raid_array[index].sub_stripes;
+	dev_stripes = btrfs_raid_array[index].dev_stripes;
+	devs_max = btrfs_raid_array[index].devs_max;
+	if (!devs_max)
+		devs_max = BTRFS_MAX_DEVS(info);
+	devs_min = btrfs_raid_array[index].devs_min;
+	devs_increment = btrfs_raid_array[index].devs_increment;
+	ncopies = btrfs_raid_array[index].ncopies;
+	nparity = btrfs_raid_array[index].nparity;
+
 	if (type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
 		if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
 			calc_size = SZ_8M;
@@ -1085,7 +1109,6 @@ int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 		if (num_stripes < 4)
 			return -ENOSPC;
 		num_stripes &= ~(u32)1;
-		sub_stripes = 2;
 		min_stripes = 4;
 	}
 	if (type & (BTRFS_BLOCK_GROUP_RAID5)) {
-- 
2.24.0

