diff mbox

[5/6] btrfs-progs: implement btrfs check --clear-space-cache v2

Message ID eb8a6a86e655b9d639b385ca6484cd6c5b932f08.1479064970.git.osandov@fb.com (mailing list archive)
State Accepted
Headers show

Commit Message

Omar Sandoval Nov. 13, 2016, 7:35 p.m. UTC 
From: Omar Sandoval <osandov@fb.com>

Signed-off-by: Omar Sandoval <osandov@fb.com>
---
 Documentation/btrfs-check.asciidoc | 14 +++++++++-----
 cmds-check.c                       | 34 +++++++++++++++++++++++++---------
 2 files changed, 34 insertions(+), 14 deletions(-)

Comments

Qu Wenruo Nov. 14, 2016, 1:44 a.m. UTC | #1 
At 11/14/2016 03:35 AM, Omar Sandoval wrote:
> From: Omar Sandoval <osandov@fb.com>
>
> Signed-off-by: Omar Sandoval <osandov@fb.com>

Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
> ---
>  Documentation/btrfs-check.asciidoc | 14 +++++++++-----
>  cmds-check.c                       | 34 +++++++++++++++++++++++++---------
>  2 files changed, 34 insertions(+), 14 deletions(-)
>
> diff --git a/Documentation/btrfs-check.asciidoc b/Documentation/btrfs-check.asciidoc
> index 5ef414e..633cbbf 100644
> --- a/Documentation/btrfs-check.asciidoc
> +++ b/Documentation/btrfs-check.asciidoc
> @@ -80,12 +80,16 @@ superblock is damaged.
>
>  --clear-space-cache v1|v2::
>  completely wipe all free space cache of given type
> -
> -NOTE: Only v1 free space cache supported is implemented.
>  +
> -Kernel mount option 'clear_cache' is only designed to rebuild free space cache
> -which is modified during the lifetime of that mount option.  It doesn't rebuild
> -all free space cache, nor clear them out.
> +For free space cache 'v1', the 'clear_cache' kernel mount option only rebuilds
> +the free space cache for block groups that are modified while the filesystem is
> +mounted with that option. Thus, using this option with 'v1' makes it possible
> +to actually clear the entire free space cache.
> ++
> +For free space cache 'v2', the 'clear_cache' kernel mount option does destroy
> +the entire free space cache. This option with 'v2' provides an alternative
> +method of clearing the free space cache that doesn't require mounting the
> +filesystem.

This is quite helpful.

The behavior of clear_cache should be the correct one.

Thanks,
Qu

>
>
>  DANGEROUS OPTIONS
> diff --git a/cmds-check.c b/cmds-check.c
> index 57c4300..0eca102 100644
> --- a/cmds-check.c
> +++ b/cmds-check.c
> @@ -11170,7 +11170,6 @@ const char * const cmd_check_usage[] = {
>  	"--chunk-root <bytenr>       use the given bytenr for the chunk tree root",
>  	"-p|--progress               indicate progress",
>  	"--clear-space-cache v1|v2   clear space cache for v1 or v2",
> -	"                            NOTE: v1 support implemented",
>  	NULL
>  };
>
> @@ -11292,13 +11291,16 @@ int cmd_check(int argc, char **argv)
>  				}
>  				break;
>  			case GETOPT_VAL_CLEAR_SPACE_CACHE:
> -				if (strcmp(optarg, "v1") != 0) {
> -					error(
> -			"only v1 support implmented, unrecognized value %s",
> -			optarg);
> +				if (strcmp(optarg, "v1") == 0) {
> +					clear_space_cache = 1;
> +				} else if (strcmp(optarg, "v2") == 0) {
> +					clear_space_cache = 2;
> +					ctree_flags |= OPEN_CTREE_INVALIDATE_FST;
> +				} else {
> +					error("invalid argument to --clear-space-cache; "
> +					      "must be v1 or v2");
>  					exit(1);
>  				}
> -				clear_space_cache = 1;
>  				ctree_flags |= OPEN_CTREE_WRITES;
>  				break;
>  		}
> @@ -11352,11 +11354,10 @@ int cmd_check(int argc, char **argv)
>
>  	global_info = info;
>  	root = info->fs_root;
> -	if (clear_space_cache) {
> +	if (clear_space_cache == 1) {
>  		if (btrfs_fs_compat_ro(info,
>  				BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE)) {
> -			error(
> -			"free space cache v2 detected, clearing not implemented");
> +			error("free space cache v2 detected; use --clear-space-cache v2");
>  			ret = 1;
>  			goto close_out;
>  		}
> @@ -11369,6 +11370,21 @@ int cmd_check(int argc, char **argv)
>  			printf("Free space cache cleared\n");
>  		}
>  		goto close_out;
> +	} else if (clear_space_cache == 2) {
> +		if (!btrfs_fs_compat_ro(info, BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE)) {
> +			printf("No free space cache v2 to clear\n");
> +			ret = 0;
> +			goto close_out;
> +		}
> +		printf("Clear free space cache v2\n");
> +		ret = btrfs_clear_free_space_tree(info);
> +		if (ret) {
> +			error("Failed to clear free space cache v2");
> +			ret = 1;
> +		} else {
> +			printf("Free space cache v2 cleared\n");
> +		}
> +		goto close_out;
>  	}
>
>  	/*
>


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diff mbox

Patch

diff --git a/Documentation/btrfs-check.asciidoc b/Documentation/btrfs-check.asciidoc
index 5ef414e..633cbbf 100644
--- a/Documentation/btrfs-check.asciidoc
+++ b/Documentation/btrfs-check.asciidoc
@@ -80,12 +80,16 @@  superblock is damaged.
 
 --clear-space-cache v1|v2::
 completely wipe all free space cache of given type
-
-NOTE: Only v1 free space cache supported is implemented.
 +
-Kernel mount option 'clear_cache' is only designed to rebuild free space cache
-which is modified during the lifetime of that mount option.  It doesn't rebuild
-all free space cache, nor clear them out.
+For free space cache 'v1', the 'clear_cache' kernel mount option only rebuilds
+the free space cache for block groups that are modified while the filesystem is
+mounted with that option. Thus, using this option with 'v1' makes it possible
+to actually clear the entire free space cache.
++
+For free space cache 'v2', the 'clear_cache' kernel mount option does destroy
+the entire free space cache. This option with 'v2' provides an alternative
+method of clearing the free space cache that doesn't require mounting the
+filesystem.
 
 
 DANGEROUS OPTIONS
diff --git a/cmds-check.c b/cmds-check.c
index 57c4300..0eca102 100644
--- a/cmds-check.c
+++ b/cmds-check.c
@@ -11170,7 +11170,6 @@  const char * const cmd_check_usage[] = {
 	"--chunk-root <bytenr>       use the given bytenr for the chunk tree root",
 	"-p|--progress               indicate progress",
 	"--clear-space-cache v1|v2   clear space cache for v1 or v2",
-	"                            NOTE: v1 support implemented",
 	NULL
 };
 
@@ -11292,13 +11291,16 @@  int cmd_check(int argc, char **argv)
 				}
 				break;
 			case GETOPT_VAL_CLEAR_SPACE_CACHE:
-				if (strcmp(optarg, "v1") != 0) {
-					error(
-			"only v1 support implmented, unrecognized value %s",
-			optarg);
+				if (strcmp(optarg, "v1") == 0) {
+					clear_space_cache = 1;
+				} else if (strcmp(optarg, "v2") == 0) {
+					clear_space_cache = 2;
+					ctree_flags |= OPEN_CTREE_INVALIDATE_FST;
+				} else {
+					error("invalid argument to --clear-space-cache; "
+					      "must be v1 or v2");
 					exit(1);
 				}
-				clear_space_cache = 1;
 				ctree_flags |= OPEN_CTREE_WRITES;
 				break;
 		}
@@ -11352,11 +11354,10 @@  int cmd_check(int argc, char **argv)
 
 	global_info = info;
 	root = info->fs_root;
-	if (clear_space_cache) {
+	if (clear_space_cache == 1) {
 		if (btrfs_fs_compat_ro(info,
 				BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE)) {
-			error(
-			"free space cache v2 detected, clearing not implemented");
+			error("free space cache v2 detected; use --clear-space-cache v2");
 			ret = 1;
 			goto close_out;
 		}
@@ -11369,6 +11370,21 @@  int cmd_check(int argc, char **argv)
 			printf("Free space cache cleared\n");
 		}
 		goto close_out;
+	} else if (clear_space_cache == 2) {
+		if (!btrfs_fs_compat_ro(info, BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE)) {
+			printf("No free space cache v2 to clear\n");
+			ret = 0;
+			goto close_out;
+		}
+		printf("Clear free space cache v2\n");
+		ret = btrfs_clear_free_space_tree(info);
+		if (ret) {
+			error("Failed to clear free space cache v2");
+			ret = 1;
+		} else {
+			printf("Free space cache v2 cleared\n");
+		}
+		goto close_out;
 	}
 
 	/*