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From: Jaegeuk Kim <jaegeuk@kernel.org>
To: Chao Yu <chao@kernel.org>
Cc: kernel-team@android.com, Daeho Jeong <daehojeong@google.com>,
	Daniel Rosenberg <drosen@google.com>,
	linux-f2fs-devel@lists.sourceforge.net
Subject: Re: [f2fs-dev] [PATCH v4 1/2] dump.f2fs: Add ability to dump folders
Date: Thu, 30 May 2024 23:41:13 +0000	[thread overview]
Message-ID: <ZlkOmapurmR-yJk3@google.com> (raw)
In-Reply-To: <aa383858-655d-4876-b3bc-52a04067b0d2@kernel.org>

On 05/29, Chao Yu wrote:
> On 2024/5/24 6:46, Daniel Rosenberg wrote:
> > This adds the ability to dump folders as well as files. Folders are
> > dumped recursively. Additionally, dumped files/folders may be directed
> > to a folder specified by -o [path] instead of ./lost_found. The -r flag
> > will dump the entire fs from the root inode. -f or -y will skip the
> > prompt before dumping, and -P will preserve the mode/owner info for the
> > created file/folder.
> > 
> > Signed-off-by: Daniel Rosenberg <drosen@google.com>
> > Reviewed-by: Daeho Jeong <daehojeong@google.com>
> > ---
> >   fsck/dump.c     | 178 ++++++++++++++++++++++++++++++++++++++----------
> >   fsck/fsck.c     |   4 +-
> >   fsck/fsck.h     |   4 +-
> >   fsck/main.c     |  29 +++++++-
> >   man/dump.f2fs.8 |  17 ++++-
> >   5 files changed, 190 insertions(+), 42 deletions(-)
> > 
> > diff --git a/fsck/dump.c b/fsck/dump.c
> > index b2e990b..fa68456 100644
> > --- a/fsck/dump.c
> > +++ b/fsck/dump.c
> > @@ -247,7 +247,26 @@ out:
> >   		printf("\n");
> >   }
> > -static void dump_data_blk(struct f2fs_sb_info *sbi, __u64 offset, u32 blkaddr)
> > +static void dump_folder_contents(struct f2fs_sb_info *sbi, u8 *bitmap,
> > +				struct f2fs_dir_entry *dentry,
> > +				__u8 (*filenames)[F2FS_SLOT_LEN], int max)
> > +{
> > +	int i;
> > +	int name_len;
> > +
> > +	for (i = 0; i < max; i++) {
> > +		if (test_bit_le(i, bitmap) == 0)
> > +			continue;
> > +		name_len = le16_to_cpu(dentry[i].name_len);
> > +		if (name_len == 1 && filenames[i][0] == '.')
> > +			continue;
> > +		if (name_len == 2 && filenames[i][0] == '.' && filenames[i][1] == '.')
> > +			continue;
> > +		dump_node(sbi, le32_to_cpu(dentry[i].ino), 1, NULL, 0, 1);
> > +	}
> > +}
> > +
> > +static void dump_data_blk(struct f2fs_sb_info *sbi, __u64 offset, u32 blkaddr, bool is_folder)
> >   {
> >   	char buf[F2FS_BLKSIZE];
> > @@ -288,12 +307,19 @@ static void dump_data_blk(struct f2fs_sb_info *sbi, __u64 offset, u32 blkaddr)
> >   		ASSERT(ret >= 0);
> >   	}
> > -	/* write blkaddr */
> > -	dev_write_dump(buf, offset, F2FS_BLKSIZE);
> > +	if (is_folder) {
> > +		struct f2fs_dentry_block *d = (struct f2fs_dentry_block *) buf;
> > +
> > +		dump_folder_contents(sbi, d->dentry_bitmap, F2FS_DENTRY_BLOCK_DENTRIES(d),
> > +					F2FS_DENTRY_BLOCK_FILENAMES(d), NR_DENTRY_IN_BLOCK);
> > +	} else {
> > +		/* write blkaddr */
> > +		dev_write_dump(buf, offset, F2FS_BLKSIZE);
> > +	}
> >   }
> >   static void dump_node_blk(struct f2fs_sb_info *sbi, int ntype,
> > -				u32 nid, u32 addr_per_block, u64 *ofs)
> > +				u32 nid, u32 addr_per_block, u64 *ofs, int is_dir)
> >   {
> >   	struct node_info ni;
> >   	struct f2fs_node *node_blk;
> > @@ -330,20 +356,20 @@ static void dump_node_blk(struct f2fs_sb_info *sbi, int ntype,
> >   		switch (ntype) {
> >   		case TYPE_DIRECT_NODE:
> >   			dump_data_blk(sbi, *ofs * F2FS_BLKSIZE,
> > -					le32_to_cpu(node_blk->dn.addr[i]));
> > +					le32_to_cpu(node_blk->dn.addr[i]), is_dir);
> >   			(*ofs)++;
> >   			break;
> >   		case TYPE_INDIRECT_NODE:
> >   			dump_node_blk(sbi, TYPE_DIRECT_NODE,
> >   					le32_to_cpu(node_blk->in.nid[i]),
> >   					addr_per_block,
> > -					ofs);
> > +					ofs, is_dir);
> >   			break;
> >   		case TYPE_DOUBLE_INDIRECT_NODE:
> >   			dump_node_blk(sbi, TYPE_INDIRECT_NODE,
> >   					le32_to_cpu(node_blk->in.nid[i]),
> >   					addr_per_block,
> > -					ofs);
> > +					ofs, is_dir);
> >   			break;
> >   		}
> >   	}
> > @@ -435,8 +461,9 @@ static int dump_inode_blk(struct f2fs_sb_info *sbi, u32 nid,
> >   	u32 i = 0;
> >   	u64 ofs = 0;
> >   	u32 addr_per_block;
> > +	bool is_dir = S_ISDIR(le16_to_cpu(node_blk->i.i_mode));
> > -	if((node_blk->i.i_inline & F2FS_INLINE_DATA)) {
> > +	if ((node_blk->i.i_inline & F2FS_INLINE_DATA)) {
> >   		DBG(3, "ino[0x%x] has inline data!\n", nid);
> >   		/* recover from inline data */
> >   		dev_write_dump(((unsigned char *)node_blk) + INLINE_DATA_OFFSET,
> > @@ -444,13 +471,25 @@ static int dump_inode_blk(struct f2fs_sb_info *sbi, u32 nid,
> >   		return -1;
> >   	}
> > +	if ((node_blk->i.i_inline & F2FS_INLINE_DENTRY)) {
> > +		void *inline_dentry = inline_data_addr(node_blk);
> > +		struct f2fs_dentry_ptr d;
> > +
> > +		make_dentry_ptr(&d, node_blk, inline_dentry, 2);
> > +
> > +		DBG(3, "ino[0x%x] has inline dentries!\n", nid);
> > +		/* recover from inline dentry */
> > +		dump_folder_contents(sbi, d.bitmap, d.dentry, d.filename, d.max);
> > +		return -1;
> > +	}
> > +
> >   	c.show_file_map_max_offset = f2fs_max_file_offset(&node_blk->i);
> >   	addr_per_block = ADDRS_PER_BLOCK(&node_blk->i);
> >   	/* check data blocks in inode */
> >   	for (i = 0; i < ADDRS_PER_INODE(&node_blk->i); i++, ofs++)
> >   		dump_data_blk(sbi, ofs * F2FS_BLKSIZE, le32_to_cpu(
> > -			node_blk->i.i_addr[get_extra_isize(node_blk) + i]));
> > +			node_blk->i.i_addr[get_extra_isize(node_blk) + i]), is_dir);
> >   	/* check node blocks in inode */
> >   	for (i = 0; i < 5; i++) {
> > @@ -458,17 +497,20 @@ static int dump_inode_blk(struct f2fs_sb_info *sbi, u32 nid,
> >   			dump_node_blk(sbi, TYPE_DIRECT_NODE,
> >   					le32_to_cpu(F2FS_INODE_I_NID(&node_blk->i, i)),
> >   					addr_per_block,
> > -					&ofs);
> > +					&ofs,
> > +					is_dir);
> >   		else if (i == 2 || i == 3)
> >   			dump_node_blk(sbi, TYPE_INDIRECT_NODE,
> >   					le32_to_cpu(F2FS_INODE_I_NID(&node_blk->i, i)),
> >   					addr_per_block,
> > -					&ofs);
> > +					&ofs,
> > +					is_dir);
> >   		else if (i == 4)
> >   			dump_node_blk(sbi, TYPE_DOUBLE_INDIRECT_NODE,
> >   					le32_to_cpu(F2FS_INODE_I_NID(&node_blk->i, i)),
> >   					addr_per_block,
> > -					&ofs);
> > +					&ofs,
> > +					is_dir);
> >   		else
> >   			ASSERT(0);
> >   	}
> > @@ -479,8 +521,51 @@ static int dump_inode_blk(struct f2fs_sb_info *sbi, u32 nid,
> >   	return 0;
> >   }
> > -static int dump_file(struct f2fs_sb_info *sbi, struct node_info *ni,
> > -				struct f2fs_node *node_blk, int force)
> > +static void dump_file(struct f2fs_sb_info *sbi, struct node_info *ni,
> > +				struct f2fs_node *node_blk, char *path)
> > +{
> > +	struct f2fs_inode *inode = &node_blk->i;
> > +	int ret;
> > +
> > +	c.dump_fd = open(path, O_TRUNC|O_CREAT|O_RDWR, 0666);
> > +	ASSERT(c.dump_fd >= 0);
> > +
> > +	/* dump file's data */
> > +	dump_inode_blk(sbi, ni->ino, node_blk);
> > +
> > +	/* adjust file size */
> > +	ret = ftruncate(c.dump_fd, le32_to_cpu(inode->i_size));
> > +	ASSERT(ret >= 0);
> > +
> > +	close(c.dump_fd);
> > +}
> > +
> > +static void dump_folder(struct f2fs_sb_info *sbi, struct node_info *ni,
> > +				struct f2fs_node *node_blk, char *path, int is_root)
> > +{
> > +	if (!is_root) {
> > +#if defined(__MINGW32__)
> > +		if (mkdir(path) < 0 && errno != EEXIST) {
> > +			MSG(0, "Failed to create directory %s\n", path);
> > +			return;
> > +		}
> > +#else
> > +		if (mkdir(path, 0777) < 0 && errno != EEXIST) {
> > +			MSG(0, "Failed to create directory %s\n", path);
> > +			return;
> > +		}
> > +#endif
> > +		ASSERT(chdir(path) == 0);
> > +	}
> > +	/* dump folder data */
> > +	dump_inode_blk(sbi, ni->ino, node_blk);
> > +	if (!is_root)
> > +		ASSERT(chdir("..") == 0);
> > +}
> > +
> > +static int dump_filesystem(struct f2fs_sb_info *sbi, struct node_info *ni,
> > +				struct f2fs_node *node_blk, int force, char *base_path,
> > +				bool is_base, bool allow_folder)
> >   {
> >   	struct f2fs_inode *inode = &node_blk->i;
> >   	u32 imode = le16_to_cpu(inode->i_mode);
> > @@ -489,6 +574,7 @@ static int dump_file(struct f2fs_sb_info *sbi, struct node_info *ni,
> >   	char path[1024] = {0};
> >   	char ans[255] = {0};
> >   	int is_encrypted = file_is_encrypt(inode);
> > +	int is_root = sbi->root_ino_num == ni->nid;
> >   	int ret;
> >   	if (is_encrypted) {
> > @@ -496,11 +582,15 @@ static int dump_file(struct f2fs_sb_info *sbi, struct node_info *ni,
> >   		return -1;
> >   	}
> > -	if ((!S_ISREG(imode) && !S_ISLNK(imode)) ||
> > -				namelen == 0 || namelen > F2FS_NAME_LEN) {
> > -		MSG(force, "Not a regular file or wrong name info\n\n");
> > +	if ((!S_ISREG(imode) && !S_ISLNK(imode) && !(S_ISDIR(imode) && allow_folder))) {
> > +		MSG(force, "Not a valid file type\n\n");
> > +		return -1;
> > +	}
> > +	if (!is_root && (namelen == 0 || namelen > F2FS_NAME_LEN)) {
> > +		MSG(force, "Wrong name info\n\n");
> >   		return -1;
> >   	}
> > +	base_path = base_path ?: "./lost_found";
> >   	if (force)
> >   		goto dump;
> > @@ -508,31 +598,49 @@ static int dump_file(struct f2fs_sb_info *sbi, struct node_info *ni,
> >   	if (c.show_file_map)
> >   		return dump_inode_blk(sbi, ni->ino, node_blk);
> > -	printf("Do you want to dump this file into ./lost_found/? [Y/N] ");
> > +	printf("Do you want to dump this %s into %s/? [Y/N] ",
> > +			S_ISREG(imode) || S_ISLNK(imode) ? "file" : "folder",
> > +			base_path);
> >   	ret = scanf("%s", ans);
> >   	ASSERT(ret >= 0);
> >   	if (!strcasecmp(ans, "y")) {
> >   dump:
> > -		ret = system("mkdir -p ./lost_found");
> > -		ASSERT(ret >= 0);
> > -
> > -		/* make a file */
> > -		strncpy(name, (const char *)inode->i_name, namelen);
> > -		name[namelen] = 0;
> > -		sprintf(path, "./lost_found/%s", name);
> > +		if (is_base) {
> > +			ASSERT(getcwd(path, sizeof(path)) != NULL);
> > +#if defined(__MINGW32__)
> > +			ret = mkdir(base_path);
> > +#else
> > +			ret = mkdir(base_path, 0777);
> > +#endif
> > -		c.dump_fd = open(path, O_TRUNC|O_CREAT|O_RDWR, 0666);
> > -		ASSERT(c.dump_fd >= 0);
> > +			ASSERT(ret == 0 || errno == EEXIST);
> > +			ASSERT(chdir(base_path) == 0);
> > +		}
> > -		/* dump file's data */
> > -		dump_inode_blk(sbi, ni->ino, node_blk);
> > +		/* make a file */
> > +		if (!is_root) {
> > +			strncpy(name, (const char *)inode->i_name, namelen);
> > +			name[namelen] = 0;
> > +		}
> > -		/* adjust file size */
> > -		ret = ftruncate(c.dump_fd, le32_to_cpu(inode->i_size));
> > -		ASSERT(ret >= 0);
> > +		if (S_ISREG(imode) || S_ISLNK(imode)) {
> > +			dump_file(sbi, ni, node_blk, name);
> > +		} else {
> > +			dump_folder(sbi, ni, node_blk, name, is_root);
> > +		}
> > -		close(c.dump_fd);
> > +#if !defined(__MINGW32__)
> > +		/* fix up mode/owner */
> > +		if (c.preserve_perms) {
> > +			if (is_root)
> > +				strncpy(name, ".", 2);
> > +			ASSERT(chmod(name, imode) == 0);
> > +			ASSERT(chown(name, inode->i_uid, inode->i_gid) == 0);
> > +		}
> > +#endif
> > +		if (is_base)
> > +			ASSERT(chdir(path) == 0);
> >   	}
> >   	return 0;
> >   }
> > @@ -582,7 +690,7 @@ void dump_node_scan_disk(struct f2fs_sb_info *sbi, nid_t nid)
> >   	free(node_blk);
> >   }
> > -int dump_node(struct f2fs_sb_info *sbi, nid_t nid, int force)
> > +int dump_node(struct f2fs_sb_info *sbi, nid_t nid, int force, char *base_path, int base, int allow_folder)
> >   {
> >   	struct node_info ni;
> >   	struct f2fs_node *node_blk;
> > @@ -617,7 +725,7 @@ int dump_node(struct f2fs_sb_info *sbi, nid_t nid, int force)
> >   			print_node_info(sbi, node_blk, force);
> >   		if (ni.ino == ni.nid)
> > -			ret = dump_file(sbi, &ni, node_blk, force);
> > +			ret = dump_filesystem(sbi, &ni, node_blk, force, base_path, base, allow_folder);
> >   	} else {
> >   		print_node_info(sbi, node_blk, force);
> >   		MSG(force, "Invalid (i)node block\n\n");
> > diff --git a/fsck/fsck.c b/fsck/fsck.c
> > index 5d345d0..7400dcf 100644
> > --- a/fsck/fsck.c
> > +++ b/fsck/fsck.c
> > @@ -1651,7 +1651,7 @@ static void print_dentry(struct f2fs_sb_info *sbi, __u8 *name,
> >   			d = d->next;
> >   		}
> >   		printf("/%s", new);
> > -		if (dump_node(sbi, le32_to_cpu(dentry[idx].ino), 0))
> > +		if (dump_node(sbi, le32_to_cpu(dentry[idx].ino), 0, NULL, 0, 0))
> >   			printf("\33[2K\r");
> >   	} else {
> >   		for (i = 1; i < depth; i++)
> > @@ -3632,7 +3632,7 @@ int fsck_verify(struct f2fs_sb_info *sbi)
> >   		if (!strcasecmp(ans, "y")) {
> >   			for (i = 0; i < fsck->nr_nat_entries; i++) {
> >   				if (f2fs_test_bit(i, fsck->nat_area_bitmap))
> > -					dump_node(sbi, i, 1);
> > +					dump_node(sbi, i, 1, NULL, 1, 0);
> >   			}
> >   		}
> >   	}
> > diff --git a/fsck/fsck.h b/fsck/fsck.h
> > index f5282e2..6cac926 100644
> > --- a/fsck/fsck.h
> > +++ b/fsck/fsck.h
> > @@ -270,12 +270,14 @@ struct dump_option {
> >   	int end_ssa;
> >   	int32_t blk_addr;
> >   	nid_t scan_nid;
> > +	int use_root_nid;
> > +	char *base_path;
> >   };
> >   extern void nat_dump(struct f2fs_sb_info *, nid_t, nid_t);
> >   extern void sit_dump(struct f2fs_sb_info *, unsigned int, unsigned int);
> >   extern void ssa_dump(struct f2fs_sb_info *, int, int);
> > -extern int dump_node(struct f2fs_sb_info *, nid_t, int);
> > +extern int dump_node(struct f2fs_sb_info *, nid_t, int, char *, int, int);
> >   extern int dump_info_from_blkaddr(struct f2fs_sb_info *, u32);
> >   extern unsigned int start_bidx_of_node(unsigned int, struct f2fs_node *);
> >   extern void dump_node_scan_disk(struct f2fs_sb_info *sbi, nid_t nid);
> > diff --git a/fsck/main.c b/fsck/main.c
> > index c4d0956..6edc902 100644
> > --- a/fsck/main.c
> > +++ b/fsck/main.c
> > @@ -34,7 +34,7 @@ struct f2fs_fsck gfsck;
> >   INIT_FEATURE_TABLE;
> > -#ifdef WITH_SLOAD
> > +#if defined(WITH_SLOAD) || defined(WITH_DUMP)
> >   static char *absolute_path(const char *file)
> >   {
> >   	char *ret;
> > @@ -384,7 +384,7 @@ void f2fs_parse_options(int argc, char *argv[])
> >   		}
> >   	} else if (!strcmp("dump.f2fs", prog)) {
> >   #ifdef WITH_DUMP
> > -		const char *option_string = "d:i:I:n:Ms:Sa:b:V";
> > +		const char *option_string = "d:fi:I:n:Mo:Prs:Sa:b:Vy";
> >   		static struct dump_option dump_opt = {
> >   			.nid = 0,	/* default root ino */
> >   			.start_nat = -1,
> > @@ -395,6 +395,8 @@ void f2fs_parse_options(int argc, char *argv[])
> >   			.end_ssa = -1,
> >   			.blk_addr = -1,
> >   			.scan_nid = 0,
> > +			.use_root_nid = 0,
> > +			.base_path = NULL,
> >   		};
> >   		c.func = DUMP;
> > @@ -456,6 +458,24 @@ void f2fs_parse_options(int argc, char *argv[])
> >   					ret = sscanf(optarg, "%x",
> >   							&dump_opt.blk_addr);
> >   				break;
> > +			case 'y':
> > +			case 'f':
> > +				c.force = 1;
> > +				break;
> > +			case 'r':
> > +				dump_opt.use_root_nid = 1;
> > +				break;
> > +			case 'o':
> > +				dump_opt.base_path = absolute_path(optarg);
> > +				break;
> > +			case 'P':
> > +#if defined(__MINGW32__)
> > +				MSG(0, "-P not supported for Windows\n");
> > +				err = EWRONG_OPT;
> > +#else
> > +				c.preserve_perms = 1;
> > +#endif
> > +				break;
> >   			case 'V':
> >   				show_version(prog);
> >   				exit(0);
> > @@ -914,6 +934,9 @@ static void do_dump(struct f2fs_sb_info *sbi)
> >   	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
> >   	u32 flag = le32_to_cpu(ckpt->ckpt_flags);
> > +	if (opt->use_root_nid)
> > +		opt->nid = sbi->root_ino_num;
> > +
> >   	if (opt->end_nat == -1)
> >   		opt->end_nat = NM_I(sbi)->max_nid;
> >   	if (opt->end_sit == -1)
> > @@ -929,7 +952,7 @@ static void do_dump(struct f2fs_sb_info *sbi)
> >   	if (opt->blk_addr != -1)
> >   		dump_info_from_blkaddr(sbi, opt->blk_addr);
> >   	if (opt->nid)
> > -		dump_node(sbi, opt->nid, 0);
> > +		dump_node(sbi, opt->nid, c.force, opt->base_path, 1, 1);
> >   	if (opt->scan_nid)
> >   		dump_node_scan_disk(sbi, opt->scan_nid);
> > diff --git a/man/dump.f2fs.8 b/man/dump.f2fs.8
> > index 94bf5f3..60d6783 100644
> > --- a/man/dump.f2fs.8
> > +++ b/man/dump.f2fs.8
> > @@ -44,7 +44,8 @@ is used to retrieve f2fs metadata (usually in a disk partition).
> >   \fIdevice\fP is the special file corresponding to the device (e.g.
> >   \fI/dev/sdXX\fP).
> > -Currently, it can retrieve 1) a file given its inode number, 2) NAT
> > +Currently, it can retrieve 1) a file or folder given its inode number
> > +(folders are dumped recursively), 2) NAT
> >   entries into a file, 3) SIT entries into a file, 4) SSA entries into
> >   a file, 5) reverse information from the given block address.
> >   .PP
> > @@ -56,6 +57,20 @@ is 0 on success and -1 on failure.
> >   .BI \-i " inode number"
> >   Specify an inode number to dump out.
> >   .TP
> > +.BI \-r
> > +Dump out from the root inode.
> > +.TP
> > +.BI \-f
> > +Do not prompt before dumping
> > +.TP
> > +.BI \-y
> > +Alias for \-f
> > +.TP
> > +.BI \-o " path"
> > +Dump inodes to the given path
> > +.BI \-P
> > +Preserve mode/owner/group for dumped inode
> > +.TP
> 
> It needs to update dump_usage() as well.
> 
> Seems f2fs mailing list is out-of-response previously, so I resend it.

Chao, can I ask for your help to write a patch for this?

Thanks,

> 
> Thanks,
> 
> >   .BI \-I " inode number"
> >   Specify an inode number and scan full disk to dump out, include history inode block
> >   .TP
> > 
> > base-commit: 5da4e5241503b385e4a7e75b1b2bb3367b38be96


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  reply	other threads:[~2024-05-30 23:41 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-05-23 22:46 [f2fs-dev] [PATCH v4 1/2] dump.f2fs: Add ability to dump folders Daniel Rosenberg via Linux-f2fs-devel
2024-05-23 22:47 ` [f2fs-dev] [PATCH v4 2/2] dump.f2fs: Fix xattr dumping Daniel Rosenberg via Linux-f2fs-devel
2024-05-23 23:34   ` Daeho Jeong
2024-05-29  6:41   ` Chao Yu
2024-05-23 23:33 ` [f2fs-dev] [PATCH v4 1/2] dump.f2fs: Add ability to dump folders Daeho Jeong
2024-05-29  6:39 ` Chao Yu
2024-05-30 23:41   ` Jaegeuk Kim [this message]
2024-05-31  1:13     ` Chao Yu

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