Re: [RFC PATCH 2/2] erofs-utils: dump: support fragments

[Yue Hu <zbestahu@gmail.com>]

Hi Xiang,

Thanks for the reviewing. I'm planning to send v2.

On Wed, 4 Jan 2023 11:13:55 +0800
Xiang Gao <hsiangkao@linux.alibaba.com> wrote:

> On 2022/12/19 17:50, Yue Hu wrote:
> > From: Yue Hu <huyue2@coolpad.com>
> > 
> > Add compressed fragments support for dump feature.
> > 
> > Signed-off-by: Yue Hu <huyue2@coolpad.com>
> > ---
> >   dump/main.c              | 78 ++++++++++++++++++++++++++++++++--------
> >   include/erofs/internal.h |  1 +
> >   lib/zmap.c               |  2 +-
> >   3 files changed, 65 insertions(+), 16 deletions(-)
> > 
> > diff --git a/dump/main.c b/dump/main.c
> > index bc4f047..d387841 100644
> > --- a/dump/main.c
> > +++ b/dump/main.c
> > @@ -14,6 +14,8 @@
> >   #include "erofs/inode.h"
> >   #include "erofs/io.h"
> >   #include "erofs/dir.h"
> > +#include "erofs/compress.h"
> > +#include "erofs/fragments.h"
> >   #include "../lib/liberofs_private.h"
> >   
> >   #ifdef HAVE_LIBUUID
> > @@ -96,6 +98,7 @@ static struct erofsdump_feature feature_lists[] = {
> >   	{ false, EROFS_FEATURE_INCOMPAT_CHUNKED_FILE, "chunked_file" },
> >   	{ false, EROFS_FEATURE_INCOMPAT_DEVICE_TABLE, "device_table" },
> >   	{ false, EROFS_FEATURE_INCOMPAT_ZTAILPACKING, "ztailpacking" },
> > +	{ false, EROFS_FEATURE_INCOMPAT_FRAGMENTS, "fragments" },
> >   };
> >   
> >   static int erofsdump_readdir(struct erofs_dir_context *ctx);
> > @@ -285,10 +288,12 @@ static int erofsdump_readdir(struct erofs_dir_context *ctx)
> >   	}
> >   
> >   	if (S_ISREG(vi.i_mode)) {
> > -		stats.files_total_origin_size += vi.i_size;
> > -		inc_file_extension_count(ctx->dname, ctx->de_namelen);
> > +		if (!erofs_is_packed_inode(&vi)) {
> > +			stats.files_total_origin_size += vi.i_size;
> > +			inc_file_extension_count(ctx->dname, ctx->de_namelen);
> > +			update_file_size_statistics(vi.i_size, true);
> > +		}
> >   		stats.files_total_size += occupied_size;
> > -		update_file_size_statistics(vi.i_size, true);
> >   		update_file_size_statistics(occupied_size, false);
> >   	}
> >   
> > @@ -320,6 +325,10 @@ static void erofsdump_show_fileinfo(bool show_extent)
> >   		"%4d: %8" PRIu64 "..%8" PRIu64 " | %7" PRIu64 " : %10" PRIu64 "..%10" PRIu64 " | %7" PRIu64 "\n",
> >   		"%4d: %8" PRIu64 "..%8" PRIu64 " | %7" PRIu64 " : %10" PRIu64 "..%10" PRIu64 " | %7" PRIu64 "  # device %u\n"
> >   	};
> > +	const char *frag_ext_fmt[] = {
> > +		"%4d: %8" PRIu64 "..%8" PRIu64 " | %7" PRIu64 "\n",
> > +		"%4d: %8" PRIu64 "..%8" PRIu64 " | %7" PRIu64 "  # device %u\n"
> > +	};  
> 
> Why do we need another fmt rather than just fill fragment extent with 

I also plan to remove this fmt in v2.

> physical addr 0?

Okay. Just leave latter physical length as empty?

> 
> >   	int err, i;
> >   	erofs_off_t size;
> >   	u16 access_mode;
> > @@ -348,16 +357,31 @@ static void erofsdump_show_fileinfo(bool show_extent)
> >   		}
> >   	}
> >   
> > +	if (erofs_inode_is_data_compressed(inode.datalayout)) {
> > +		err = z_erofs_fill_inode_lazy(&inode);
> > +		if (err) {
> > +			erofs_err("read inode map header failed @ nid %llu",
> > +				  inode.nid | 0ULL);
> > +			return;
> > +		}
> > +	}  
> 
> Why do we need to call z_erofs_fill_inode_lazy here?

Used to check if the file has fragment. If yes, i think 'Compression ratio' can not be showed
exactly. 

So, I'd like to show fragment information related instead as below:

NID: 715   Links: 1   Layout: 1   Fragment: entire file

NID: 715   Links: 1   Layout: 3   Fragment: tail of file

> 
> > +
> >   	err = erofs_get_occupied_size(&inode, &size);
> >   	if (err) {
> >   		erofs_err("get file size failed @ nid %llu", inode.nid | 0ULL);
> >   		return;
> >   	}
> >   
> > -	err = erofs_get_pathname(inode.nid, path, sizeof(path));
> > -	if (err < 0) {
> > -		erofs_err("file path not found @ nid %llu", inode.nid | 0ULL);
> > -		return;  
> 
> Can we just ignore pathname if it doesn't exist?

Okay.

> 
> > +	if (erofs_is_packed_inode(&inode) { > +		strncpy(path, EROFS_PACKED_INODE, sizeof(path) - 1);
> > +		path[sizeof(path) - 1] = '\0';
> > +	} else {
> > +		err = erofs_get_pathname(inode.nid, path, sizeof(path));
> > +		if (err < 0) {
> > +			erofs_err("file path not found @ nid %llu",
> > +				  inode.nid | 0ULL);
> > +			return;
> > +		}
> >   	}
> >   
> >   	strftime(timebuf, sizeof(timebuf),
> > @@ -372,9 +396,13 @@ static void erofsdump_show_fileinfo(bool show_extent)
> >   		file_category_types[erofs_mode_to_ftype(inode.i_mode)]);
> >   	fprintf(stdout, "NID: %" PRIu64 "   ", inode.nid);
> >   	fprintf(stdout, "Links: %u   ", inode.i_nlink);
> > -	fprintf(stdout, "Layout: %d   Compression ratio: %.2f%%\n",
> > -		inode.datalayout,
> > -		(double)(100 * size) / (double)(inode.i_size));
> > +	if (inode.z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER)
> > +		fprintf(stdout, "Layout: %d   Fragment: %s\n",
> > +			inode.datalayout, size ? "partial" : "full");
> > +	else
> > +		fprintf(stdout, "Layout: %d   Compression ratio: %.2f%%\n",
> > +			inode.datalayout,
> > +			(double)(100 * size) / (double)(inode.i_size));
> >   	fprintf(stdout, "Inode size: %d   ", inode.inode_isize);
> >   	fprintf(stdout, "Extent size: %u   ", inode.extent_isize);
> >   	fprintf(stdout,	"Xattr size: %u\n", inode.xattr_isize);
> > @@ -404,7 +432,8 @@ static void erofsdump_show_fileinfo(bool show_extent)
> >   	if (!dumpcfg.show_extent)
> >   		return;
> >   
> > -	fprintf(stdout, "\n Ext:   logical offset   |  length :     physical offset    |  length\n");
> > +	fprintf(stdout, "\n Ext:   logical offset   |  length%s\n",
> > +			size ? " :     physical offset    |  length" : "");
> >   	while (map.m_la < inode.i_size) {
> >   		struct erofs_map_dev mdev;
> >   
> > @@ -425,10 +454,17 @@ static void erofsdump_show_fileinfo(bool show_extent)
> >   			return;
> >   		}
> >   
> > -		fprintf(stdout, ext_fmt[!!mdev.m_deviceid], extent_count++,
> > -			map.m_la, map.m_la + map.m_llen, map.m_llen,
> > -			mdev.m_pa, mdev.m_pa + map.m_plen, map.m_plen,
> > -			mdev.m_deviceid);
> > +		if (map.m_flags & EROFS_MAP_FRAGMENT)
> > +			fprintf(stdout, frag_ext_fmt[!!mdev.m_deviceid],
> > +				extent_count++,
> > +				map.m_la, map.m_la + map.m_llen, map.m_llen,
> > +				mdev.m_deviceid);  
> 
> except for the last fragment extent, the other extents all have physical 
> addr and length...

It's true.

What bothers me is how to better show fragment extent based on current format (especially
no physical address and offset for fragment extent).

Now, i think the fragment extent should be showed like below (just use a '0' to represent it)?

a) the whole file is a fragment:

 Ext:   logical offset   |  length :     physical offset    |  length
   1:        0..    1046 |    1046 :    0

b) the tail of file is a fragment:

 Ext:   logical offset   |  length :     physical offset    |  length
   0:        0..   19672 |   19672 :    1314816..   1323008 |    8192
    ...
  13:   165989..  182474 |   16485 :    1421312..   1429504 |    8192
  14:   182474..  196435 |   13961 :    0

> 
> > +		else
> > +			fprintf(stdout, ext_fmt[!!mdev.m_deviceid],
> > +				extent_count++,
> > +				map.m_la, map.m_la + map.m_llen, map.m_llen,
> > +				mdev.m_pa, mdev.m_pa + map.m_plen, map.m_plen,
> > +				mdev.m_deviceid);
> >   		map.m_la += map.m_llen;
> >   	}
> >   	fprintf(stdout, "%s: %d extents found\n", path, extent_count);
> > @@ -537,6 +573,15 @@ static void erofsdump_print_statistic(void)
> >   		erofs_err("read dir failed");
> >   		return;
> >   	}
> > +	if (erofs_sb_has_fragments()) {
> > +		err = erofsdump_readdir(&(struct erofs_dir_context) {
> > +					.de_nid = sbi.packed_nid
> > +					});  
> 
> why do we need this?

Since some status need to be updated such as stats.files_total_size.

> 
> Thanks,
> Gao Xiang
> 
> > +		if (err) {
> > +			erofs_err("read packed inode failed");
> > +			return;
> > +		}
> > +	}
> >   	erofsdump_file_statistic();
> >   	erofsdump_filesize_distribution("Original",
> >   			stats.file_original_size,
> > @@ -563,6 +608,9 @@ static void erofsdump_show_superblock(void)
> >   			sbi.xattr_blkaddr);
> >   	fprintf(stdout, "Filesystem root nid:                          %llu\n",
> >   			sbi.root_nid | 0ULL);
> > +	if (erofs_sb_has_fragments())
> > +		fprintf(stdout, "Filesystem packed nid:                        %llu\n",
> > +				sbi.packed_nid | 0ULL);
> >   	fprintf(stdout, "Filesystem inode count:                       %llu\n",
> >   			sbi.inos | 0ULL);
> >   	fprintf(stdout, "Filesystem created:                           %s",
> > diff --git a/include/erofs/internal.h b/include/erofs/internal.h
> > index 206913c..947894d 100644
> > --- a/include/erofs/internal.h
> > +++ b/include/erofs/internal.h
> > @@ -383,6 +383,7 @@ int erofs_listxattr(struct erofs_inode *vi, char *buffer, size_t buffer_size);
> >   
> >   /* zmap.c */
> >   int z_erofs_fill_inode(struct erofs_inode *vi);
> > +int z_erofs_fill_inode_lazy(struct erofs_inode *vi);
> >   int z_erofs_map_blocks_iter(struct erofs_inode *vi,
> >   			    struct erofs_map_blocks *map, int flags);
> >   
> > diff --git a/lib/zmap.c b/lib/zmap.c
> > index 89e9da1..41e0713 100644
> > --- a/lib/zmap.c
> > +++ b/lib/zmap.c
> > @@ -29,7 +29,7 @@ int z_erofs_fill_inode(struct erofs_inode *vi)
> >   	return 0;
> >   }
> >   
> > -static int z_erofs_fill_inode_lazy(struct erofs_inode *vi)
> > +int z_erofs_fill_inode_lazy(struct erofs_inode *vi)
> >   {
> >   	int ret;
> >   	erofs_off_t pos;