[1/2] Update btrfs filesystem df command

Commit Message

Goffredo Baroncelli Oct. 3, 2012, 11:43 a.m. UTC

The  command  btrfs  filesystem  df is used to query the
status of the chunks, how many space on the disk(s) are used  by
the  chunks,  how many space are available in the chunks, and an
estimation of the free space of the filesystem.
---
 cmds-filesystem.c |  264 +++++++++++++++++++++++++++++++++++++++++++----------
 1 file changed, 215 insertions(+), 49 deletions(-)

Comments

Ilya Dryomov Oct. 3, 2012, 3:02 p.m. UTC | #1

On Wed, Oct 03, 2012 at 01:43:15PM +0200, Goffredo Baroncelli wrote:
> The  command  btrfs  filesystem  df is used to query the
> status of the chunks, how many space on the disk(s) are used  by
> the  chunks,  how many space are available in the chunks, and an
> estimation of the free space of the filesystem.
> ---
>  cmds-filesystem.c |  264 +++++++++++++++++++++++++++++++++++++++++++----------
>  1 file changed, 215 insertions(+), 49 deletions(-)
> 
> diff --git a/cmds-filesystem.c b/cmds-filesystem.c
> index b1457de..6c3ebdc 100644
> --- a/cmds-filesystem.c
> +++ b/cmds-filesystem.c

(snipped)

> +static int cmd_disk_free(int argc, char **argv)
> +{
> +
> +	int 	flags=DF_SHOW_SUMMARY|DF_SHOW_DETAIL|DF_HUMAN_UNIT;
> +	int	i, more_than_one=0;
> +
> +	if (check_argc_min(argc, 2))
> +		usage(cmd_disk_free_usage);
> +
> +	for(i=1; i< argc ; i++){
> +		if(!strcmp(argv[i],"-d"))
> +			flags &= ~DF_SHOW_DETAIL;
> +		else if(!strcmp(argv[i],"-s"))
> +			flags &= ~DF_SHOW_SUMMARY;
> +		else if(!strcmp(argv[i],"-k"))
> +			flags &= ~DF_HUMAN_UNIT;
> +		else{
> +			int r;
> +			if(more_than_one)
> +				printf("\n");
> +			r = _cmd_disk_free(argv[i], flags);
> +			if( r ) return r;
> +			more_than_one=1;
> +		}

Is there any reason getopt(), or better yet, getopt_long() won't work?

> +
> +	}
> +
> +	return 0;
> +}	
> +	
> +
> +	
>  static int uuid_search(struct btrfs_fs_devices *fs_devices, char *search)
>  {
>  	char uuidbuf[37];
> @@ -529,7 +695,7 @@ static int cmd_label(int argc, char **argv)
>  
>  const struct cmd_group filesystem_cmd_group = {
>  	filesystem_cmd_group_usage, NULL, {
> -		{ "df", cmd_df, cmd_df_usage, NULL, 0 },
> +		{ "df", cmd_disk_free, cmd_disk_free_usage, NULL, 0 },

If this command is going to replace df, you should change the function
name back to cmd_df.

Thanks,

		Ilya
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Goffredo Baroncelli Oct. 3, 2012, 4:34 p.m. UTC | #2

On 10/03/2012 05:02 PM, Ilya Dryomov wrote:
> On Wed, Oct 03, 2012 at 01:43:15PM +0200, Goffredo Baroncelli wrote:
>> The  command  btrfs  filesystem  df is used to query the
>> status of the chunks, how many space on the disk(s) are used  by
>> the  chunks,  how many space are available in the chunks, and an
>> estimation of the free space of the filesystem.
>> ---
>>   cmds-filesystem.c |  264 +++++++++++++++++++++++++++++++++++++++++++----------
>>   1 file changed, 215 insertions(+), 49 deletions(-)
>>
>> diff --git a/cmds-filesystem.c b/cmds-filesystem.c
>> index b1457de..6c3ebdc 100644
>> --- a/cmds-filesystem.c
>> +++ b/cmds-filesystem.c
>
> (snipped)
>
>> +static int cmd_disk_free(int argc, char **argv)
>> +{
>> +
>> +	int 	flags=DF_SHOW_SUMMARY|DF_SHOW_DETAIL|DF_HUMAN_UNIT;
>> +	int	i, more_than_one=0;
>> +
>> +	if (check_argc_min(argc, 2))
>> +		usage(cmd_disk_free_usage);
>> +
>> +	for(i=1; i<  argc ; i++){
>> +		if(!strcmp(argv[i],"-d"))
>> +			flags&= ~DF_SHOW_DETAIL;
>> +		else if(!strcmp(argv[i],"-s"))
>> +			flags&= ~DF_SHOW_SUMMARY;
>> +		else if(!strcmp(argv[i],"-k"))
>> +			flags&= ~DF_HUMAN_UNIT;
>> +		else{
>> +			int r;
>> +			if(more_than_one)
>> +				printf("\n");
>> +			r = _cmd_disk_free(argv[i], flags);
>> +			if( r ) return r;
>> +			more_than_one=1;
>> +		}
>
> Is there any reason getopt(), or better yet, getopt_long() won't work?

In the beginning there were also the switches +d, +s, +k, then I dropped 
them. So I leaved this style. The code is simple enough to not justify a 
change.

>
>> +
>> +	}
>> +
>> +	return 0;
>> +}	
>> +	
>> +
>> +	
>>   static int uuid_search(struct btrfs_fs_devices *fs_devices, char *search)
>>   {
>>   	char uuidbuf[37];
>> @@ -529,7 +695,7 @@ static int cmd_label(int argc, char **argv)
>>
>>   const struct cmd_group filesystem_cmd_group = {
>>   	filesystem_cmd_group_usage, NULL, {
>> -		{ "df", cmd_df, cmd_df_usage, NULL, 0 },
>> +		{ "df", cmd_disk_free, cmd_disk_free_usage, NULL, 0 },
>
> If this command is going to replace df, you should change the function
> name back to cmd_df.

I was never convinced to use 'df'. At the beginning when I wrote the 
first parser of btrfs, was suggested (not by me) to use "long" command 
and allow the parser to match a contracted command until there was any 
ambiguity. I suggested to use disk-free, but everybody were confortable 
with df.. so I leaved it as "official name". But I prefer for the 
internal code a more verbose name.


>
> Thanks,

Thanks you for your review.

>
> 		Ilya
>

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Goffredo Baroncelli Oct. 3, 2012, 5:09 p.m. UTC | #3

On 10/03/2012 05:02 PM, Ilya Dryomov wrote:
>> +static int cmd_disk_free(int argc, char **argv)
>> >  +{
>> >  +
>> >  +	int 	flags=DF_SHOW_SUMMARY|DF_SHOW_DETAIL|DF_HUMAN_UNIT;
>> >  +	int	i, more_than_one=0;
>> >  +
>> >  +	if (check_argc_min(argc, 2))
>> >  +		usage(cmd_disk_free_usage);
>> >  +
>> >  +	for(i=1; i<  argc ; i++){
>> >  +		if(!strcmp(argv[i],"-d"))
>> >  +			flags&= ~DF_SHOW_DETAIL;
>> >  +		else if(!strcmp(argv[i],"-s"))
>> >  +			flags&= ~DF_SHOW_SUMMARY;
>> >  +		else if(!strcmp(argv[i],"-k"))
>> >  +			flags&= ~DF_HUMAN_UNIT;
>> >  +		else{
>> >  +			int r;
>> >  +			if(more_than_one)
>> >  +				printf("\n");
>> >  +			r = _cmd_disk_free(argv[i], flags);
>> >  +			if( r ) return r;
>> >  +			more_than_one=1;
>> >  +		}
> Is there any reason getopt(), or better yet, getopt_long() won't work?

I re-changed idea: I will use getopt()


>

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Ilya Dryomov Oct. 3, 2012, 5:20 p.m. UTC | #4

On Wed, Oct 03, 2012 at 06:34:38PM +0200, Goffredo Baroncelli wrote:
> On 10/03/2012 05:02 PM, Ilya Dryomov wrote:
> >On Wed, Oct 03, 2012 at 01:43:15PM +0200, Goffredo Baroncelli wrote:
> >>The  command  btrfs  filesystem  df is used to query the
> >>status of the chunks, how many space on the disk(s) are used  by
> >>the  chunks,  how many space are available in the chunks, and an
> >>estimation of the free space of the filesystem.
> >>---
> >>  cmds-filesystem.c |  264 +++++++++++++++++++++++++++++++++++++++++++----------
> >>  1 file changed, 215 insertions(+), 49 deletions(-)
> >>
> >>diff --git a/cmds-filesystem.c b/cmds-filesystem.c
> >>index b1457de..6c3ebdc 100644
> >>--- a/cmds-filesystem.c
> >>+++ b/cmds-filesystem.c
> >
> >(snipped)
> >
> >>+static int cmd_disk_free(int argc, char **argv)
> >>+{
> >>+
> >>+	int 	flags=DF_SHOW_SUMMARY|DF_SHOW_DETAIL|DF_HUMAN_UNIT;
> >>+	int	i, more_than_one=0;
> >>+
> >>+	if (check_argc_min(argc, 2))
> >>+		usage(cmd_disk_free_usage);
> >>+
> >>+	for(i=1; i<  argc ; i++){
> >>+		if(!strcmp(argv[i],"-d"))
> >>+			flags&= ~DF_SHOW_DETAIL;
> >>+		else if(!strcmp(argv[i],"-s"))
> >>+			flags&= ~DF_SHOW_SUMMARY;
> >>+		else if(!strcmp(argv[i],"-k"))
> >>+			flags&= ~DF_HUMAN_UNIT;
> >>+		else{
> >>+			int r;
> >>+			if(more_than_one)
> >>+				printf("\n");
> >>+			r = _cmd_disk_free(argv[i], flags);
> >>+			if( r ) return r;
> >>+			more_than_one=1;
> >>+		}
> >
> >Is there any reason getopt(), or better yet, getopt_long() won't work?
> 
> In the beginning there were also the switches +d, +s, +k, then I
> dropped them. So I leaved this style. The code is simple enough to
> not justify a change.

It's not a matter of style.  It is generally expected that several short
options can be specified after one dash.  Further, if somebody else were
to add an option with an optional parameter, they'd have to spend time
rewriting your stuff.

In addition to that, other parts of progs already use getopt() in
similar situations.  One example would be the scrub subgroup: scrub
commands are equally simple (a few short switches, no parameters), and
yet getopt() is used.

> 
> >
> >>+
> >>+	}
> >>+
> >>+	return 0;
> >>+}	
> >>+	
> >>+
> >>+	
> >>  static int uuid_search(struct btrfs_fs_devices *fs_devices, char *search)
> >>  {
> >>  	char uuidbuf[37];
> >>@@ -529,7 +695,7 @@ static int cmd_label(int argc, char **argv)
> >>
> >>  const struct cmd_group filesystem_cmd_group = {
> >>  	filesystem_cmd_group_usage, NULL, {
> >>-		{ "df", cmd_df, cmd_df_usage, NULL, 0 },
> >>+		{ "df", cmd_disk_free, cmd_disk_free_usage, NULL, 0 },
> >
> >If this command is going to replace df, you should change the function
> >name back to cmd_df.
> 
> I was never convinced to use 'df'. At the beginning when I wrote the
> first parser of btrfs, was suggested (not by me) to use "long"
> command and allow the parser to match a contracted command until
> there was any ambiguity. I suggested to use disk-free, but everybody
> were confortable with df.. so I leaved it as "official name". But I
> prefer for the internal code a more verbose name.

Well, all your patch is doing is extending the functionality of an
existing command.  The "official name" for that command is "df", and you
are not changing its name.  Why change the name of an existing function?

Thanks,

		Ilya
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Goffredo Baroncelli Oct. 3, 2012, 5:38 p.m. UTC | #5

Hi,
On 10/03/2012 07:20 PM, Ilya Dryomov wrote:
>>>>   	filesystem_cmd_group_usage, NULL, {
>>>> >  >>-		{ "df", cmd_df, cmd_df_usage, NULL, 0 },
>>>> >  >>+		{ "df", cmd_disk_free, cmd_disk_free_usage, NULL, 0 },
>>> >  >
>>> >  >If this command is going to replace df, you should change the function
>>> >  >name back to cmd_df.
>> >
>> >  I was never convinced to use 'df'. At the beginning when I wrote the
>> >  first parser of btrfs, was suggested (not by me) to use "long"
>> >  command and allow the parser to match a contracted command until
>> >  there was any ambiguity. I suggested to use disk-free, but everybody
>> >  were confortable with df.. so I leaved it as "official name". But I
>> >  prefer for the internal code a more verbose name.
> Well, all your patch is doing is extending the functionality of an
> existing command.  The "official name" for that command is "df", and you
> are not changing its name.

I would like change the name of the command from df to disk-free. 
Unfortunately (for me) Chris ask to leaved the old name...

 > Why change the name of an existing function?

Strictly speaking, I never changed the name of the function. At the 
beginning I added another command (who was named disk-usage), then Chris 
asked to replace df with the new one. So I removed the old one.
Seeing the patch it seems that I changed the name, but the truth is that 
I added a new one then  removed the old one. Due to how the patch is 
generated it seems another thing.
But this doesn't change too much.

The point is that the function name doesn't match the command name. It 
is not the single case: look at the function cmd_send_start() 
(associated to the send command), cmd_defrag() )associated to the 
command defragment....)


BR
G.Baroncelli
>
> Thanks,
>
> 		Ilya
>

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Patch

diff --git a/cmds-filesystem.c b/cmds-filesystem.c
index b1457de..6c3ebdc 100644
--- a/cmds-filesystem.c
+++ b/cmds-filesystem.c
@@ -22,6 +22,7 @@ 
 #include <errno.h>
 #include <uuid/uuid.h>
 #include <ctype.h>
+#include <sys/vfs.h>
 
 #include "kerncompat.h"
 #include "ctree.h"
@@ -39,25 +40,55 @@  static const char * const filesystem_cmd_group_usage[] = {
 	NULL
 };
 
-static const char * const cmd_df_usage[] = {
-	"btrfs filesystem df <path>",
-	"Show space usage information for a mount point",
-	NULL
-};
+static u64 disk_size( char *path){
+	struct statfs	sfs;
+
+	if( statfs(path, &sfs) < 0 )
+		return 0;
+	else
+		return sfs.f_bsize * sfs.f_blocks;
+
+}
+
+static void print_string(char *s, int w)
+{
+	int	i;
+
+	printf("%s", s);
+	for( i = strlen(s) ; i < w ; i++ ) 
+		putchar(' ');
+}
+
+#define DF_SHOW_SUMMARY 	(1<<1)
+#define DF_SHOW_DETAIL		(1<<2)
+#define DF_HUMAN_UNIT		(1<<3)
+
+static void pretty_sizes_r(u64 size, int w, int mode)
+{
+	if( mode & DF_HUMAN_UNIT ){
+		char *s = pretty_sizes(size);
+		printf("%*s", w, s);
+		free(s);
+	} else {
+		printf("%*llu", w, size/1024);
+
+	}
+}
 
-static int cmd_df(int argc, char **argv)
+static int _cmd_disk_free(char *path, int mode)
 {
 	struct btrfs_ioctl_space_args *sargs;
 	u64 count = 0, i;
 	int ret;
 	int fd;
-	int e;
-	char *path;
-
-	if (check_argc_exact(argc, 2))
-		usage(cmd_df_usage);
-
-	path = argv[1];
+	int e, width;
+	u64  total_disk;		/* fielsystem size == sum of
+					   disk sizes */
+	u64  total_chunks;		/* sum of chunks sizes on disk(s) */
+	u64  total_used;		/* logical space used */
+	u64  total_free;		/* logical space un-used */
+	double K;
+	
 
 	fd = open_file_or_dir(path);
 	if (fd < 0) {
@@ -103,56 +134,191 @@  static int cmd_df(int argc, char **argv)
 		return ret;
 	}
 
-	for (i = 0; i < sargs->total_spaces; i++) {
-		char description[80];
-		char *total_bytes;
-		char *used_bytes;
-		int written = 0;
-		u64 flags = sargs->spaces[i].flags;
+	total_disk = disk_size(path);
+	e = errno;
+	if( total_disk == 0 ){
+		fprintf(stderr, "ERROR: couldn't get space info on '%s' - %s\n",
+			path, strerror(e));
+		close(fd);
+		free(sargs);
+		return ret;
+	}
+		
+	total_chunks = total_used = total_free = 0;
 
-		memset(description, 0, 80);
+	for (i = 0; i < sargs->total_spaces; i++) {
+		int  ratio=1;
+		u64  allocated;
 
-		if (flags & BTRFS_BLOCK_GROUP_DATA) {
-			if (flags & BTRFS_BLOCK_GROUP_METADATA) {
-				snprintf(description, 14, "%s",
-					 "Data+Metadata");
-				written += 13;
-			} else {
-				snprintf(description, 5, "%s", "Data");
-				written += 4;
-			}
-		} else if (flags & BTRFS_BLOCK_GROUP_SYSTEM) {
-			snprintf(description, 7, "%s", "System");
-			written += 6;
-		} else if (flags & BTRFS_BLOCK_GROUP_METADATA) {
-			snprintf(description, 9, "%s", "Metadata");
-			written += 8;
-		}
+		u64 flags = sargs->spaces[i].flags;
 
 		if (flags & BTRFS_BLOCK_GROUP_RAID0) {
-			snprintf(description+written, 8, "%s", ", RAID0");
-			written += 7;
+			ratio=1;
 		} else if (flags & BTRFS_BLOCK_GROUP_RAID1) {
-			snprintf(description+written, 8, "%s", ", RAID1");
-			written += 7;
+			ratio=2;
 		} else if (flags & BTRFS_BLOCK_GROUP_DUP) {
-			snprintf(description+written, 6, "%s", ", DUP");
-			written += 5;
+			ratio=2;
 		} else if (flags & BTRFS_BLOCK_GROUP_RAID10) {
-			snprintf(description+written, 9, "%s", ", RAID10");
-			written += 8;
+			ratio=2;
+		} else {
+			ratio=1;
 		}
 
-		total_bytes = pretty_sizes(sargs->spaces[i].total_bytes);
-		used_bytes = pretty_sizes(sargs->spaces[i].used_bytes);
-		printf("%s: total=%s, used=%s\n", description, total_bytes,
-		       used_bytes);
+		allocated = sargs->spaces[i].total_bytes * ratio;
+
+		total_chunks += allocated;
+		total_used += sargs->spaces[i].used_bytes;
+		total_free += (sargs->spaces[i].total_bytes - 
+					sargs->spaces[i].used_bytes);
+
+	}
+	K = ((double)total_used + (double)total_free) /
+	                (double)total_chunks;
+
+	if( mode & DF_HUMAN_UNIT )
+		width = 12;
+	else
+		width = 18;
+
+	printf("Path: %s\n", path);
+	if( mode & DF_SHOW_SUMMARY ){
+		printf("Summary:\n");
+		printf("  Disk_size:\t\t");
+		pretty_sizes_r(total_disk, width, mode);
+		printf("\n  Disk_allocated:\t");
+		pretty_sizes_r(total_chunks, width, mode);
+		printf("\n  Disk_unallocated:\t"); 
+		pretty_sizes_r(total_disk-total_chunks, width, mode);
+		printf("\n  Logical_size:\t\t"); 
+		pretty_sizes_r(total_used+total_free, width, mode);
+		printf("\n  Used:\t\t\t"); 
+		pretty_sizes_r(total_used, width, mode);
+		printf("\n  Free_(Estimated):\t");
+		pretty_sizes_r((u64)(K*total_disk-total_used), width, mode);
+		printf("\t(Max: ");
+		pretty_sizes_r(total_disk-total_chunks+total_free, 
+				0, mode );
+		printf(", Min: ");
+		pretty_sizes_r((total_disk-total_chunks)/2+total_free, 
+				0, mode );
+		printf(")\n  Data_to_disk_ratio:\t%*.0f %%\n",
+			width-2, K*100);
+	}
+
+	if( ( mode & DF_SHOW_DETAIL ) && ( mode & DF_SHOW_SUMMARY ) )
+		printf("\n");
+
+	if( mode & DF_SHOW_DETAIL ){
+		/* Remember: the terminals have maximum 80 columns
+		   do not believe to who says otherwise */
+		printf("Details:\n");
+		printf("  %-12s%-8s%*s%*s%*s\n",
+			"Chunk-type", 
+			"Mode",
+			width, "Chunk-size", 
+			1+width, "Logical-size", 
+			width, "Used"
+		);
+
+		for (i = 0; i < sargs->total_spaces; i++) {
+			char *description="";
+			int  ratio=1;
+			char *r_mode;
+			u64 allocated;
+
+			u64 flags = sargs->spaces[i].flags;
+
+			if (flags & BTRFS_BLOCK_GROUP_DATA) {
+				if (flags & BTRFS_BLOCK_GROUP_METADATA){
+					description = "Data+M.data";
+				} else {
+					description = "Data";
+				}
+			} else if (flags & BTRFS_BLOCK_GROUP_SYSTEM) {
+				description = "System";
+			} else if (flags & BTRFS_BLOCK_GROUP_METADATA) {
+				description = "Metadata";
+			}
+
+			if (flags & BTRFS_BLOCK_GROUP_RAID0) {
+				r_mode = "RAID0";
+				ratio=1;
+			} else if (flags & BTRFS_BLOCK_GROUP_RAID1) {
+				r_mode = "RAID1";
+				ratio=2;
+			} else if (flags & BTRFS_BLOCK_GROUP_DUP) {
+				r_mode = "DUP";
+				ratio=2;
+			} else if (flags & BTRFS_BLOCK_GROUP_RAID10) {
+				r_mode = "RAID10";
+				ratio=2;
+			} else {
+				r_mode = "Single";
+				ratio=1;
+			}
+
+			allocated = sargs->spaces[i].total_bytes * ratio;
+
+			printf("  ");
+			print_string(description,12);
+			print_string(r_mode, 8);
+			pretty_sizes_r(allocated, width, mode);
+			pretty_sizes_r(sargs->spaces[i].total_bytes ,
+				    width+1, mode);
+	
+			pretty_sizes_r(sargs->spaces[i].used_bytes, 
+						width, mode);
+			printf("\n");
+
+		}
 	}
 	free(sargs);
 
 	return 0;
 }
 
+static const char * const cmd_disk_free_usage[] = {
+	"btrfs filesystem df [-d][-s][-k] <path> [<path>..]",
+	"Show space usage information for a mount point(s).",
+	"",
+	"-k\tSet KB (1024 bytes) as unit",
+	"-s\tDon't show the summary section",
+	"-d\tDon't show the detail section",
+	NULL
+};
+
+static int cmd_disk_free(int argc, char **argv)
+{
+
+	int 	flags=DF_SHOW_SUMMARY|DF_SHOW_DETAIL|DF_HUMAN_UNIT;
+	int	i, more_than_one=0;
+
+	if (check_argc_min(argc, 2))
+		usage(cmd_disk_free_usage);
+
+	for(i=1; i< argc ; i++){
+		if(!strcmp(argv[i],"-d"))
+			flags &= ~DF_SHOW_DETAIL;
+		else if(!strcmp(argv[i],"-s"))
+			flags &= ~DF_SHOW_SUMMARY;
+		else if(!strcmp(argv[i],"-k"))
+			flags &= ~DF_HUMAN_UNIT;
+		else{
+			int r;
+			if(more_than_one)
+				printf("\n");
+			r = _cmd_disk_free(argv[i], flags);
+			if( r ) return r;
+			more_than_one=1;
+		}
+
+	}
+
+	return 0;
+}	
+	
+
+	
 static int uuid_search(struct btrfs_fs_devices *fs_devices, char *search)
 {
 	char uuidbuf[37];
@@ -529,7 +695,7 @@  static int cmd_label(int argc, char **argv)
 
 const struct cmd_group filesystem_cmd_group = {
 	filesystem_cmd_group_usage, NULL, {
-		{ "df", cmd_df, cmd_df_usage, NULL, 0 },
+		{ "df", cmd_disk_free, cmd_disk_free_usage, NULL, 0 },
 		{ "show", cmd_show, cmd_show_usage, NULL, 0 },
 		{ "sync", cmd_sync, cmd_sync_usage, NULL, 0 },
 		{ "defragment", cmd_defrag, cmd_defrag_usage, NULL, 0 },