[PATCH 0/2] nodiscard for device add

[PATCH 0/2] nodiscard for device add

[David Sterba]

David Sterba (2):
  btrfs-progs: use better name for nodiscard variable and flip the logic
  btrfs-progs: add nodiscard option to device add

 cmds-device.c  | 34 +++++++++++++++++++++++++++++-----
 man/btrfs.8.in | 11 +++++++++--
 mkfs.c         |  8 ++++----
 utils.c        |  6 ++++--
 utils.h        |  2 +-
 5 files changed, 47 insertions(+), 14 deletions(-)

-- 
1.8.3.1

[PATCH 1/2] btrfs-progs: use better name for nodiscard variable and flip the logic

[David Sterba]

Signed-off-by: David Sterba <dsterba@suse.cz>
---
 mkfs.c  | 8 ++++----
 utils.c | 4 ++--
 utils.h | 2 +-
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/mkfs.c b/mkfs.c
index 3ac00ba..40da546 100644
--- a/mkfs.c
+++ b/mkfs.c
@@ -1324,7 +1324,7 @@ int main(int ac, char **av)
 	int mixed = 0;
 	int data_profile_opt = 0;
 	int metadata_profile_opt = 0;
-	int nodiscard = 0;
+	int discard = 1;
 	int ssd = 0;
 	int force_overwrite = 0;
 
@@ -1409,7 +1409,7 @@ int main(int ac, char **av)
 				source_dir_set = 1;
 				break;
 			case 'K':
-				nodiscard=1;
+				discard = 0;
 				break;
 			default:
 				print_usage();
@@ -1507,7 +1507,7 @@ int main(int ac, char **av)
 		}
 		first_file = file;
 		ret = btrfs_prepare_device(fd, file, zero_end, &dev_block_count,
-					   block_count, &mixed, nodiscard);
+					   block_count, &mixed, discard);
 		if (block_count && block_count > dev_block_count) {
 			fprintf(stderr, "%s is smaller than requested size\n", file);
 			exit(1);
@@ -1614,7 +1614,7 @@ int main(int ac, char **av)
 			continue;
 		}
 		ret = btrfs_prepare_device(fd, file, zero_end, &dev_block_count,
-					   block_count, &mixed, nodiscard);
+					   block_count, &mixed, discard);
 		mixed = old_mixed;
 		BUG_ON(ret);
 
diff --git a/utils.c b/utils.c
index 134bf80..bb1bcdb 100644
--- a/utils.c
+++ b/utils.c
@@ -569,7 +569,7 @@ int btrfs_add_to_fsid(struct btrfs_trans_handle *trans,
 }
 
 int btrfs_prepare_device(int fd, char *file, int zero_end, u64 *block_count_ret,
-			   u64 max_block_count, int *mixed, int nodiscard)
+			   u64 max_block_count, int *mixed, int discard)
 {
 	u64 block_count;
 	u64 bytenr;
@@ -596,7 +596,7 @@ int btrfs_prepare_device(int fd, char *file, int zero_end, u64 *block_count_ret,
 		*mixed = 1;
 	}
 
-	if (!nodiscard) {
+	if (discard) {
 		/*
 		 * We intentionally ignore errors from the discard ioctl.  It is
 		 * not necessary for the mkfs functionality but just an optimization.
diff --git a/utils.h b/utils.h
index 6c2553a..6bf7880 100644
--- a/utils.h
+++ b/utils.h
@@ -34,7 +34,7 @@ int make_btrfs(int fd, const char *device, const char *label,
 int btrfs_make_root_dir(struct btrfs_trans_handle *trans,
 			struct btrfs_root *root, u64 objectid);
 int btrfs_prepare_device(int fd, char *file, int zero_end, u64 *block_count_ret,
-			 u64 max_block_count, int *mixed, int nodiscard);
+			 u64 max_block_count, int *mixed, int discard);
 int btrfs_add_to_fsid(struct btrfs_trans_handle *trans,
 		      struct btrfs_root *root, int fd, char *path,
 		      u64 block_count, u32 io_width, u32 io_align,
-- 
1.8.3.1

[PATCH 2/2] btrfs-progs: add nodiscard option to device add

[David Sterba]

Same as for mkfs.

Signed-off-by: David Sterba <dsterba@suse.cz>
---
 cmds-device.c  | 34 +++++++++++++++++++++++++++++-----
 man/btrfs.8.in | 11 +++++++++--
 utils.c        |  2 ++
 3 files changed, 40 insertions(+), 7 deletions(-)

diff --git a/cmds-device.c b/cmds-device.c
index 800a050..12c802e 100644
--- a/cmds-device.c
+++ b/cmds-device.c
@@ -22,6 +22,7 @@
 #include <sys/ioctl.h>
 #include <errno.h>
 #include <sys/stat.h>
+#include <getopt.h>
 
 #include "kerncompat.h"
 #include "ctree.h"
@@ -36,8 +37,9 @@ static const char * const device_cmd_group_usage[] = {
 };
 
 static const char * const cmd_add_dev_usage[] = {
-	"btrfs device add <device> [<device>...] <path>",
+	"btrfs device add [options] <device> [<device>...] <path>",
 	"Add a device to a filesystem",
+	"-K|--nodiscard    do not perform whole device TRIM",
 	NULL
 };
 
@@ -46,11 +48,33 @@ static int cmd_add_dev(int argc, char **argv)
 	char	*mntpnt;
 	int	i, fdmnt, ret=0, e;
 	DIR	*dirstream = NULL;
+	int discard = 1;
+
+	while (1) {
+		int long_index;
+		static struct option long_options[] = {
+			{ "nodiscard", optional_argument, NULL, 'K'},
+			{ 0, 0, 0, 0 }
+		};
+		int c = getopt_long(argc, argv, "K", long_options,
+					&long_index);
+		if (c < 0)
+			break;
+		switch (c) {
+		case 'K':
+			discard = 0;
+			break;
+		default:
+			usage(cmd_add_dev_usage);
+		}
+	}
 
-	if (check_argc_min(argc, 3))
+	argc = argc - optind;
+
+	if (check_argc_min(argc, 2))
 		usage(cmd_add_dev_usage);
 
-	mntpnt = argv[argc - 1];
+	mntpnt = argv[optind + argc - 1];
 
 	fdmnt = open_file_or_dir(mntpnt, &dirstream);
 	if (fdmnt < 0) {
@@ -58,7 +82,7 @@ static int cmd_add_dev(int argc, char **argv)
 		return 1;
 	}
 
-	for (i = 1; i < argc - 1; i++ ){
+	for (i = optind; i < optind + argc - 1; i++){
 		struct btrfs_ioctl_vol_args ioctl_args;
 		int	devfd, res;
 		u64 dev_block_count = 0;
@@ -99,7 +123,7 @@ static int cmd_add_dev(int argc, char **argv)
 		}
 
 		res = btrfs_prepare_device(devfd, argv[i], 1, &dev_block_count,
-					   0, &mixed, 0);
+					   0, &mixed, discard);
 		if (res) {
 			fprintf(stderr, "ERROR: Unable to init '%s'\n", argv[i]);
 			close(devfd);
diff --git a/man/btrfs.8.in b/man/btrfs.8.in
index 61ffe8d..03126b4 100644
--- a/man/btrfs.8.in
+++ b/man/btrfs.8.in
@@ -47,7 +47,7 @@ btrfs \- control a btrfs filesystem
 \fBbtrfs\fP \fB[filesystem] balance status\fP [-v] \fI<path>\fP
 .PP
 .PP
-\fBbtrfs\fP \fBdevice add\fP \fI<device>\fP [\fI<device>...\fP] \fI<path>\fP
+\fBbtrfs\fP \fBdevice add\fP [-K] \fI<device>\fP [\fI<device>...\fP] \fI<path>\fP
 .PP
 \fBbtrfs\fP \fBdevice delete\fP \fI<device>\fP [\fI<device>...\fP] \fI<path>\fP
 .PP
@@ -386,8 +386,15 @@ be verbose
 .RE
 .TP
 
-\fBdevice add\fR\fI <dev> \fP[\fI<dev>...\fP] \fI<path>\fR
+\fBdevice add\fR\fI [-K] <dev> \fP[\fI<dev>...\fP] \fI<path>\fR
 Add device(s) to the filesystem identified by \fI<path>\fR.
+If applicable, a whole device discard (TRIM) operation is performed.
+.RS
+
+\fIOptions\fR
+.IP "\fB-K|--nodiscard\fP" 5
+do not perform discard by default
+.RE
 .TP
 
 \fBdevice delete\fR\fI <dev> \fP[\fI<dev>...\fP] \fI<path>\fR
diff --git a/utils.c b/utils.c
index bb1bcdb..68aa534 100644
--- a/utils.c
+++ b/utils.c
@@ -597,6 +597,8 @@ int btrfs_prepare_device(int fd, char *file, int zero_end, u64 *block_count_ret,
 	}
 
 	if (discard) {
+		fprintf(stderr, "Performing full device TRIM (%s) ...\n",
+				pretty_size(block_count));
 		/*
 		 * We intentionally ignore errors from the discard ioctl.  It is
 		 * not necessary for the mkfs functionality but just an optimization.
-- 
1.8.3.1