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Message-ID: <20131204045736.GF20409@gmail.com> Date: Wed, 4 Dec 2013 12:57:36 +0800 From: Zheng Liu <gnehzuil.liu@...il.com> To: "Darrick J. Wong" <darrick.wong@...cle.com> Cc: linux-ext4@...r.kernel.org, Theodore Ts'o <tytso@....edu>, Zheng Liu <wenqing.lz@...bao.com> Subject: Re: [PATCH v2 09/28] libext2fs: handle inline data in dir iterator function On Tue, Dec 03, 2013 at 02:13:49PM -0800, Darrick J. Wong wrote: > On Tue, Dec 03, 2013 at 08:11:36PM +0800, Zheng Liu wrote: > > From: Zheng Liu <wenqing.lz@...bao.com> > > > > Inline_data is handled in dir iterator because a lot of commands use > > this function to traverse directory entries in debugfs. We need to > > handle inline_data individually because inline_data is saved in two > > places. One is in i_block, and another is in ibody extended attribute. > > > > After applied this commit, the following commands in debugfs can > > support the inline_data feature: > > - cd > > - chroot > > - link* > > - ls > > - ncheck > > - pwd > > - unlink > > > > * TODO: Inline_data doesn't expand to ibody extended attribute because > > link command doesn't handle DIR_NO_SPACE error until now. But if we > > have already expanded inline data to ibody ea area, link command can > > occupy this space. > > A patch for this TODO is coming, right? TBH, I don't have a patch for this because I don't know why ext2fs_link doesn't handle DIR_NO_SPACE error. So I will try to fix it later. > > > Signed-off-by: Theodore Ts'o <tytso@....edu> > > Signed-off-by: Zheng Liu <wenqing.lz@...bao.com> > > --- > > lib/ext2fs/Makefile.in | 8 +++ > > lib/ext2fs/Makefile.pq | 1 + > > lib/ext2fs/dir_iterate.c | 62 +++++++++++----- > > lib/ext2fs/ext2_err.et.in | 3 + > > lib/ext2fs/ext2_fs.h | 10 +++ > > lib/ext2fs/ext2fs.h | 1 + > > lib/ext2fs/ext2fsP.h | 11 +++ > > lib/ext2fs/inline_data.c | 175 +++++++++++++++++++++++++++++++++++++++++++++ > > lib/ext2fs/swapfs.c | 12 +++- > > 9 files changed, 265 insertions(+), 18 deletions(-) > > create mode 100644 lib/ext2fs/inline_data.c > > > > diff --git a/lib/ext2fs/Makefile.in b/lib/ext2fs/Makefile.in > > index e1e6216..4d011c9 100644 > > --- a/lib/ext2fs/Makefile.in > > +++ b/lib/ext2fs/Makefile.in > > @@ -59,6 +59,7 @@ OBJS= $(DEBUGFS_LIB_OBJS) $(RESIZE_LIB_OBJS) $(E2IMAGE_LIB_OBJS) \ > > ind_block.o \ > > initialize.o \ > > inline.o \ > > + inline_data.o \ > > inode.o \ > > io_manager.o \ > > ismounted.o \ > > @@ -133,6 +134,7 @@ SRCS= ext2_err.c \ > > $(srcdir)/ind_block.c \ > > $(srcdir)/initialize.c \ > > $(srcdir)/inline.c \ > > + $(srcdir)/inline_data.c \ > > $(srcdir)/inode.c \ > > $(srcdir)/inode_io.c \ > > $(srcdir)/imager.c \ > > @@ -758,6 +760,12 @@ inline.o: $(srcdir)/inline.c $(top_builddir)/lib/config.h \ > > $(srcdir)/ext2_fs.h $(srcdir)/ext3_extents.h $(top_srcdir)/lib/et/com_err.h \ > > $(srcdir)/ext2_io.h $(top_builddir)/lib/ext2fs/ext2_err.h \ > > $(srcdir)/ext2_ext_attr.h $(srcdir)/bitops.h > > +inline_data.o: $(srcdir)/inline_data.c $(top_builddir)/lib/config.h \ > > + $(top_builddir)/lib/dirpaths.h $(srcdir)/ext2_fs.h \ > > + $(top_builddir)/lib/ext2fs/ext2_types.h $(srcdir)/ext2fs.h \ > > + $(srcdir)/ext2_fs.h $(srcdir)/ext3_extents.h $(top_srcdir)/lib/et/com_err.h \ > > + $(srcdir)/ext2_io.h $(top_builddir)/lib/ext2fs/ext2_err.h \ > > + $(srcdir)/ext2_ext_attr.h $(srcdir)/bitops.h > > inode.o: $(srcdir)/inode.c $(top_builddir)/lib/config.h \ > > $(top_builddir)/lib/dirpaths.h $(srcdir)/ext2_fs.h \ > > $(top_builddir)/lib/ext2fs/ext2_types.h $(srcdir)/ext2fsP.h \ > > diff --git a/lib/ext2fs/Makefile.pq b/lib/ext2fs/Makefile.pq > > index 2f7b654..89082a7 100644 > > --- a/lib/ext2fs/Makefile.pq > > +++ b/lib/ext2fs/Makefile.pq > > @@ -27,6 +27,7 @@ OBJS= alloc.obj \ > > icount.obj \ > > initialize.obj \ > > inline.obj \ > > + inline_data.obj \ > > inode.obj \ > > ismounted.obj \ > > link.obj \ > > diff --git a/lib/ext2fs/dir_iterate.c b/lib/ext2fs/dir_iterate.c > > index 8be0ac2..1624371 100644 > > --- a/lib/ext2fs/dir_iterate.c > > +++ b/lib/ext2fs/dir_iterate.c > > @@ -127,6 +127,12 @@ errcode_t ext2fs_dir_iterate2(ext2_filsys fs, > > ext2fs_process_dir_block, &ctx); > > if (!block_buf) > > ext2fs_free_mem(&ctx.buf); > > + if (retval == EXT2_ET_INLINE_DATA_CANT_ITERATE) { > > + ctx.flags |= DIRENT_FLAG_INCLUDE_INLINE_DATA; > > + retval = ext2fs_inline_data_dir_iterate(fs, dir, > > + ext2fs_process_dir_block, > > + &ctx); > > + } > > if (retval) > > return retval; > > return ctx.errcode; > > @@ -189,30 +195,40 @@ int ext2fs_process_dir_block(ext2_filsys fs, > > int ret = 0; > > int changed = 0; > > int do_abort = 0; > > - unsigned int rec_len, size; > > + unsigned int rec_len, size, buflen; > > int entry; > > struct ext2_dir_entry *dirent; > > int csum_size = 0; > > + int inline_data; > > + errcode_t retval = 0; > > > > if (blockcnt < 0) > > return 0; > > > > entry = blockcnt ? DIRENT_OTHER_FILE : DIRENT_DOT_FILE; > > > > - ctx->errcode = ext2fs_read_dir_block4(fs, *blocknr, ctx->buf, 0, > > - ctx->dir); > > - if (ctx->errcode) > > - return BLOCK_ABORT; > > + /* If a dir has inline data, we don't need to read block */ > > + inline_data = !!(ctx->flags & DIRENT_FLAG_INCLUDE_INLINE_DATA); > > + if (!inline_data) { > > + ctx->errcode = ext2fs_read_dir_block4(fs, *blocknr, ctx->buf, 0, > > + ctx->dir); > > + if (ctx->errcode) > > + return BLOCK_ABORT; > > + /* If we handle a normal dir, we traverse the entire block */ > > + buflen = fs->blocksize; > > + } else { > > + buflen = ctx->buflen; > > Since we don't swap i_block[] when we're reading in the inode, who calls > ext2fs_dirent_swab_in()? Good catch! I will call this on ext2fs_inline_data_dir_iterate(). > > > + } > > > > if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super, > > EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) > > csum_size = sizeof(struct ext2_dir_entry_tail); > > > > - while (offset < fs->blocksize) { > > + while (offset < buflen) { > > dirent = (struct ext2_dir_entry *) (ctx->buf + offset); > > if (ext2fs_get_rec_len(fs, dirent, &rec_len)) > > return BLOCK_ABORT; > > - if (((offset + rec_len) > fs->blocksize) || > > + if (((offset + rec_len) > buflen) || > > (rec_len < 8) || > > ((rec_len % 4) != 0) || > > ((ext2fs_dirent_name_len(dirent)+8) > rec_len)) { > > @@ -220,7 +236,13 @@ int ext2fs_process_dir_block(ext2_filsys fs, > > return BLOCK_ABORT; > > } > > if (!dirent->inode) { > > - if ((offset == fs->blocksize - csum_size) && > > + /* > > + * We just need to check metadata_csum when this > > + * dir hasn't inline data. That means that 'buflen' > > + * should be blocksize. > > + */ > > + if (!inline_data && > > + (offset == buflen - csum_size) && > > (dirent->rec_len == csum_size) && > > (dirent->name_len == EXT2_DIR_NAME_LEN_CSUM)) { > > if (!(ctx->flags & DIRENT_FLAG_INCLUDE_CSUM)) > > @@ -234,7 +256,7 @@ int ext2fs_process_dir_block(ext2_filsys fs, > > (next_real_entry > offset) ? > > DIRENT_DELETED_FILE : entry, > > dirent, offset, > > - fs->blocksize, ctx->buf, > > + buflen, ctx->buf, > > ctx->priv_data); > > if (entry < DIRENT_OTHER_FILE) > > entry++; > > @@ -272,13 +294,21 @@ next: > > } > > > > if (changed) { > > - ctx->errcode = ext2fs_write_dir_block4(fs, *blocknr, ctx->buf, > > - 0, ctx->dir); > > - if (ctx->errcode) > > - return BLOCK_ABORT; > > + if (!inline_data) { > > + ctx->errcode = ext2fs_write_dir_block4(fs, *blocknr, > > + ctx->buf, > > + 0, ctx->dir); > > + if (ctx->errcode) > > + return BLOCK_ABORT; > > + } else { > > + /* > > + * return BLOCK_CHANGED to notify caller that inline > > + * data has been changed > > + */ > > I don't think I like overloading the meaning of BLOCK_CHANGED here. For a > non-inlinedata file, the iterator function returning BLOCK_CHANGED means that > the lblk->pblk mapping changed, whereas for an inline data file, it means that > the block *contents* have changed. > > At best, the two meanings ought to be documented wherever BLOCK_CHANGED is > defined, though I think I'd prefer a new flag BLOCK_INLINE_DATA_CHANGED to > handle this situation, because otherwise the meaning of the flag is > context-dependent and therefore more difficult to reason about. > > Separate flags also gives us the ability to check for programming errors, such > as someone returning BLOCK_CHANGED on inlinedata files or returning > BLOCK_INLINE_DATA_CHANGED on !inlinedata files. Fair enough. > > > + retval = BLOCK_CHANGED; > > Who calls ext2fs_dirent_swab_out()? Ditto. > > > + } > > } > > if (do_abort) > > - return BLOCK_ABORT; > > - return 0; > > + return retval | BLOCK_ABORT; > > + return retval; > > } > > - > > diff --git a/lib/ext2fs/ext2_err.et.in b/lib/ext2fs/ext2_err.et.in > > index b819a90..0781145 100644 > > --- a/lib/ext2fs/ext2_err.et.in > > +++ b/lib/ext2fs/ext2_err.et.in > > @@ -500,4 +500,7 @@ ec EXT2_ET_EA_KEY_NOT_FOUND, > > ec EXT2_ET_EA_NO_SPACE, > > "Insufficient space to store extended attribute data" > > > > +ec EXT2_ET_NO_INLINE_DATA, > > + "Inode doesn't have inline data" > > + > > end > > diff --git a/lib/ext2fs/ext2_fs.h b/lib/ext2fs/ext2_fs.h > > index 6a28d55..5ab16ae 100644 > > --- a/lib/ext2fs/ext2_fs.h > > +++ b/lib/ext2fs/ext2_fs.h > > @@ -914,4 +914,14 @@ struct mmp_struct { > > */ > > #define EXT4_MMP_MIN_CHECK_INTERVAL 5 > > > > +/* > > + * Minimum size of inline data. > > + */ > > +#define EXT4_MIN_INLINE_DATA_SIZE ((sizeof(__u32) * EXT2_N_BLOCKS)) > > + > > +/* > > + * Size of a parent inode in inline data directory. > > + */ > > +#define EXT4_INLINE_DATA_DOTDOT_SIZE (4) > > + > > #endif /* _LINUX_EXT2_FS_H */ > > diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h > > index e251435..c5b73fd 100644 > > --- a/lib/ext2fs/ext2fs.h > > +++ b/lib/ext2fs/ext2fs.h > > @@ -438,6 +438,7 @@ struct ext2_extent_info { > > #define DIRENT_FLAG_INCLUDE_EMPTY 1 > > #define DIRENT_FLAG_INCLUDE_REMOVED 2 > > #define DIRENT_FLAG_INCLUDE_CSUM 4 > > +#define DIRENT_FLAG_INCLUDE_INLINE_DATA 8 > > > > #define DIRENT_DOT_FILE 1 > > #define DIRENT_DOT_DOT_FILE 2 > > diff --git a/lib/ext2fs/ext2fsP.h b/lib/ext2fs/ext2fsP.h > > index 80d2d0a..5ab6084 100644 > > --- a/lib/ext2fs/ext2fsP.h > > +++ b/lib/ext2fs/ext2fsP.h > > @@ -50,6 +50,7 @@ struct dir_context { > > ext2_ino_t dir; > > int flags; > > char *buf; > > + unsigned int buflen; > > int (*func)(ext2_ino_t dir, > > int entry, > > struct ext2_dir_entry *dirent, > > @@ -87,6 +88,16 @@ extern int ext2fs_process_dir_block(ext2_filsys fs, > > int ref_offset, > > void *priv_data); > > > > +extern errcode_t ext2fs_inline_data_dir_iterate(ext2_filsys fs, > > + ext2_ino_t ino, > > + int (*func)(ext2_filsys fs, > > + blk64_t *blocknr, > > + e2_blkcnt_t blockcnt, > > + blk64_t ref_blk, > > + int ref_offset, > > + void *priv_data), > > + void *priv_data); > > + > > /* Generic numeric progress meter */ > > > > struct ext2fs_numeric_progress_struct { > > diff --git a/lib/ext2fs/inline_data.c b/lib/ext2fs/inline_data.c > > new file mode 100644 > > index 0000000..cc2954d > > --- /dev/null > > +++ b/lib/ext2fs/inline_data.c > > @@ -0,0 +1,175 @@ > > +/* > > + * inline_data.c --- data in inode > > + * > > + * Copyright (C) 2012 Zheng Liu <wenqing.lz@...bao.com> > > + * > > + * %Begin-Header% > > + * This file may be redistributed under the terms of the GNU library > > + * General Public License, version 2. > > + * %End-Header% > > + */ > > + > > +#include "config.h" > > +#include <stdio.h> > > +#include <time.h> > > + > > +#include "ext2_fs.h" > > +#include "ext2_ext_attr.h" > > + > > +#include "ext2fs.h" > > +#include "ext2fsP.h" > > + > > +struct ext2_inline_data { > > + ext2_filsys fs; > > + ext2_ino_t ino; > > + size_t ea_size; /* the size of inline data in ea area */ > > + char *ea_data; > > Should this be a void* since the file data type is opaque to the library? I will fix it. > > > +}; > > + > > +static errcode_t ext2fs_inline_data_ea_set(struct ext2_inline_data *data) > > +{ > > + struct ext2_xattr_handle *handle; > > + errcode_t retval; > > + > > + retval = ext2fs_xattrs_open(data->fs, data->ino, &handle); > > + if (retval) > > + return retval; > > + > > + retval = ext2fs_xattrs_read(handle); > > + if (retval) > > + goto err; > > + > > + retval = ext2fs_xattr_set(handle, "system.data", > > + data->ea_data, data->ea_size); > > + if (retval) > > + goto err; > > + > > + retval = ext2fs_xattrs_write(handle); > > + > > +err: > > + (void) ext2fs_xattrs_close(&handle); > > + return retval; > > +} > > + > > +errcode_t ext2fs_inline_data_ea_get(struct ext2_inline_data *data) > > +{ > > + struct ext2_xattr_handle *handle; > > + errcode_t retval; > > + > > + data->ea_size = 0; > > + data->ea_data = 0; > > + > > + retval = ext2fs_xattrs_open(data->fs, data->ino, &handle); > > + if (retval) > > + return retval; > > + > > + retval = ext2fs_xattrs_read(handle); > > + if (retval) > > + goto err; > > + > > + retval = ext2fs_xattr_get(handle, "system.data", > > + (void **)&data->ea_data, &data->ea_size); > > + if (retval) > > + goto err; > > + > > +err: > > + (void) ext2fs_xattrs_close(&handle); > > + return retval; > > +} > > + > > + > > +errcode_t ext2fs_inline_data_dir_iterate(ext2_filsys fs, > > + ext2_ino_t ino, > > + int (*func)(ext2_filsys fs, > > + blk64_t *blocknr, > > + e2_blkcnt_t blockcnt, > > + blk64_t ref_blk, > > + int ref_offset, > > + void *priv_data), > > + void *priv_data) > > +{ > > + struct dir_context *ctx; > > + struct ext2_inode inode; > > + struct ext2_dir_entry dirent; > > + struct ext2_inline_data data; > > + errcode_t retval = 0; > > + e2_blkcnt_t blockcnt = 0; > > + > > + ctx = (struct dir_context *)priv_data; > > + > > + retval = ext2fs_read_inode(fs, ino, &inode); > > + if (retval) > > + goto out; > > + > > + if (!(inode.i_flags & EXT4_INLINE_DATA_FL)) > > + return EXT2_ET_NO_INLINE_DATA; > > + > > + if (!LINUX_S_ISDIR(inode.i_mode)) { > > + retval = EXT2_ET_NO_DIRECTORY; > > + goto out; > > + } > > + > > + /* we first check '.' and '..' dir */ > > + dirent.inode = ino; > > + dirent.name_len = 1; > > + ext2fs_set_rec_len(fs, EXT2_DIR_REC_LEN(2), &dirent); > > + dirent.name[0] = '.'; > > + dirent.name[1] = '\0'; > > + ctx->buf = (char *)&dirent; > > + ext2fs_get_rec_len(fs, &dirent, &ctx->buflen); > > + retval |= (*func)(fs, 0, blockcnt++, 0, 0, priv_data); > > + if (retval & BLOCK_ABORT) > > + goto out; > > + > > + dirent.inode = ext2fs_le32_to_cpu(inode.i_block[0]); > > + dirent.name_len = 2; > > + ext2fs_set_rec_len(fs, EXT2_DIR_REC_LEN(3), &dirent); > > + dirent.name[0] = '.'; > > + dirent.name[1] = '.'; > > + dirent.name[2] = '\0'; > > + ctx->buf = (char *)&dirent; > > + ext2fs_get_rec_len(fs, &dirent, &ctx->buflen); > > + retval |= (*func)(fs, 0, blockcnt++, 0, 0, priv_data); > > + if (retval & BLOCK_CHANGED) { > > + errcode_t err; > > + > > + inode.i_block[0] = ext2fs_cpu_to_le32(dirent.inode); > > + err = ext2fs_write_inode(fs, ino, &inode); > > + if (err) > > + goto out; > > + } > > + if (retval & BLOCK_ABORT) > > + goto out; > > + > > + ctx->buf = (char *)inode.i_block + EXT4_INLINE_DATA_DOTDOT_SIZE; > > + ctx->buflen = EXT4_MIN_INLINE_DATA_SIZE - EXT4_INLINE_DATA_DOTDOT_SIZE; > > + retval |= (*func)(fs, 0, blockcnt++, 0, 0, priv_data); > > + if (retval & BLOCK_CHANGED) { > > + errcode_t err; > > + > > + err = ext2fs_write_inode(fs, ino, &inode); > > + if (err) > > + goto out; > > + } > > + if (retval & BLOCK_ABORT) > > + goto out; > > + > > + data.fs = fs; > > + data.ino = ino; > > + retval = ext2fs_inline_data_ea_get(&data); > > + if (retval) > > + goto out; > > + if (data.ea_size > 0) { > > + ctx->buf = data.ea_data; > > + ctx->buflen = data.ea_size; > > + retval |= (*func)(fs, 0, blockcnt++, 0, 0, priv_data); > > + if (retval & BLOCK_CHANGED) > > + ext2fs_inline_data_ea_set(&data); > > + ext2fs_free_mem(&data.ea_data); > > + ctx->buf = 0; > > + } > > + > > +out: > > + retval |= BLOCK_ERROR; > > + return retval & BLOCK_ERROR ? ctx->errcode : 0; > > +} > > diff --git a/lib/ext2fs/swapfs.c b/lib/ext2fs/swapfs.c > > index 1295e81..cfbe5dd 100644 > > --- a/lib/ext2fs/swapfs.c > > +++ b/lib/ext2fs/swapfs.c > > @@ -207,6 +207,7 @@ void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t, > > { > > unsigned i, has_data_blocks, extra_isize, attr_magic; > > int has_extents = 0; > > + int has_inline_data = 0; > > int islnk = 0; > > __u32 *eaf, *eat; > > > > @@ -233,12 +234,19 @@ void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t, > > (struct ext2_inode *) t); > > if (hostorder && (f->i_flags & EXT4_EXTENTS_FL)) > > has_extents = 1; > > + if (hostorder && (f->i_flags & EXT4_INLINE_DATA_FL)) > > + has_inline_data = 1; > > t->i_flags = ext2fs_swab32(f->i_flags); > > if (!hostorder && (t->i_flags & EXT4_EXTENTS_FL)) > > has_extents = 1; > > + if (!hostorder && (f->i_flags & EXT4_INLINE_DATA_FL)) > > + has_inline_data = 1; > > t->i_dir_acl = ext2fs_swab32(f->i_dir_acl); > > - /* extent data are swapped on access, not here */ > > - if (!has_extents && (!islnk || has_data_blocks)) { > > + /* > > + * Extent data are swapped on access, not here > > + * Inline data are not swapped beside parent ino is accessed > > From the other patches it looks like the parent ino is swapped on access too. > > I'm confused about what this comment is trying to say, though the code here > says that inline data is swapped on access (if at all). OK. I will clarify this. Thanks, - Zheng -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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