On Thu, 20 Feb 2014, Darrick J. Wong wrote:
> Date: Thu, 20 Feb 2014 11:39:24 -0800
> From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> To: Lukas Czerner <lczerner@xxxxxxxxxx>
> Cc: linux-ext4@xxxxxxxxxxxxxxx, tytso@xxxxxxx
> Subject: Re: [PATCH] e2fsprogs: introduce ext2fs_close_free() helper
>
> On Thu, Feb 20, 2014 at 04:02:29PM +0100, Lukas Czerner wrote:
> > Currently there are many uses of ext2fs_close() which might be wrong.
> > First of all ext2fs_close() does not set the ext2_filsys pointer to NULL
> > so the caller is responsible for clearing it, however there are some
> > cases there we do not do it.
> >
> > Second of all very small number of users of ext2fs_close() actually
> > check the return value. If there is a problem in ext2fs_close() it will
> > not even free the ext2_filsys structure, but majority of users expect it
> > to do so.
> >
> > To fix both problems this commit introduces a new helper
> > ext2fs_close_free() which will not only check for the return value and
> > free the ext2_filsys structure if the call to ext2fs_close2() failed,
> > but it will also set the ext2_filsys pointer to NULL.
> >
> > Replace every use of ext2fs_close() in e2fsprogs tools with
> > ext2fs_close_free() - there is no real reason to keep using
> > ext2fs_close().
>
> I think I like this. :)
>
> Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Hi Ted,
are you planning to take this in ?
Thanks!
-Lukas
>
> --D
> >
> > Signed-off-by: Lukas Czerner <lczerner@xxxxxxxxxx>
> > ---
> > debugfs/debugfs.c | 6 ++----
> > e2fsck/scantest.c | 2 +-
> > e2fsck/unix.c | 20 ++++++++------------
> > e2fsck/util.c | 2 +-
> > lib/ext2fs/closefs.c | 12 ++++++++++++
> > lib/ext2fs/ext2fs.h | 1 +
> > lib/ext2fs/mkjournal.c | 2 +-
> > lib/ext2fs/tst_bitmaps.c | 12 ++++--------
> > misc/dumpe2fs.c | 6 +++---
> > misc/e2freefrag.c | 2 +-
> > misc/e2image.c | 4 ++--
> > misc/e4defrag.c | 2 +-
> > misc/mke2fs.c | 8 ++++----
> > misc/tune2fs.c | 6 +++---
> > resize/main.c | 2 +-
> > resize/resize2fs.c | 2 +-
> > 16 files changed, 46 insertions(+), 43 deletions(-)
> >
> > diff --git a/debugfs/debugfs.c b/debugfs/debugfs.c
> > index d8d6d76..7db6bda 100644
> > --- a/debugfs/debugfs.c
> > +++ b/debugfs/debugfs.c
> > @@ -131,10 +131,9 @@ static void open_filesystem(char *device, int open_flags, blk64_t superblock,
> > return;
> >
> > errout:
> > - retval = ext2fs_close(current_fs);
> > + retval = ext2fs_close_free(¤t_fs);
> > if (retval)
> > com_err(device, retval, "while trying to close filesystem");
> > - current_fs = NULL;
> > }
> >
> > void do_open_filesys(int argc, char **argv)
> > @@ -238,10 +237,9 @@ static void close_filesystem(NOARGS)
> > if (retval)
> > com_err("ext2fs_write_block_bitmap", retval, 0);
> > }
> > - retval = ext2fs_close(current_fs);
> > + retval = ext2fs_close_free(¤t_fs);
> > if (retval)
> > com_err("ext2fs_close", retval, 0);
> > - current_fs = NULL;
> > return;
> > }
> >
> > diff --git a/e2fsck/scantest.c b/e2fsck/scantest.c
> > index 16380b3..6131141 100644
> > --- a/e2fsck/scantest.c
> > +++ b/e2fsck/scantest.c
> > @@ -133,7 +133,7 @@ int main (int argc, char *argv[])
> > }
> >
> >
> > - ext2fs_close(fs);
> > + ext2fs_close_free(&fs);
> >
> > print_resource_track(&global_rtrack);
> >
> > diff --git a/e2fsck/unix.c b/e2fsck/unix.c
> > index 429f1cd..593106b 100644
> > --- a/e2fsck/unix.c
> > +++ b/e2fsck/unix.c
> > @@ -451,8 +451,7 @@ static void check_if_skip(e2fsck_t ctx)
> > }
> > log_out(ctx, "\n");
> > skip:
> > - ext2fs_close(fs);
> > - ctx->fs = NULL;
> > + ext2fs_close_free(&fs);
> > e2fsck_free_context(ctx);
> > exit(FSCK_OK);
> > }
> > @@ -1304,12 +1303,12 @@ restart:
> > orig_superblock = ctx->superblock;
> > get_backup_sb(ctx, fs, ctx->filesystem_name, io_ptr);
> > if (fs)
> > - ext2fs_close(fs);
> > + ext2fs_close_free(&fs);
> > orig_retval = retval;
> > retval = try_open_fs(ctx, flags, io_ptr, &fs);
> > if ((orig_retval == 0) && retval != 0) {
> > if (fs)
> > - ext2fs_close(fs);
> > + ext2fs_close_free(&fs);
> > log_out(ctx, _("%s: %s while using the "
> > "backup blocks"),
> > ctx->program_name,
> > @@ -1403,7 +1402,7 @@ failure:
> > * reopen the filesystem after we get the device size.
> > */
> > if (pctx.errcode == EBUSY) {
> > - ext2fs_close(fs);
> > + ext2fs_close_free(&fs);
> > need_restart++;
> > pctx.errcode =
> > ext2fs_get_device_size2(ctx->filesystem_name,
> > @@ -1460,8 +1459,7 @@ failure:
> > /*
> > * Restart in order to reopen fs but this time start mmp.
> > */
> > - ext2fs_close(fs);
> > - ctx->fs = NULL;
> > + ext2fs_close_free(&fs);
> > flags &= ~EXT2_FLAG_SKIP_MMP;
> > goto restart;
> > }
> > @@ -1511,8 +1509,7 @@ failure:
> > ctx->device_name);
> > fatal_error(ctx, 0);
> > }
> > - ext2fs_close(ctx->fs);
> > - ctx->fs = 0;
> > + ext2fs_close_free(&ctx->fs);
> > ctx->flags |= E2F_FLAG_RESTARTED;
> > goto restart;
> > }
> > @@ -1691,7 +1688,7 @@ no_journal:
> > _("while resetting context"));
> > fatal_error(ctx, 0);
> > }
> > - ext2fs_close(fs);
> > + ext2fs_close_free(&fs);
> > goto restart;
> > }
> > if (run_result & E2F_FLAG_CANCEL) {
> > @@ -1773,8 +1770,7 @@ no_journal:
> > io_channel_flush(ctx->fs->io);
> > print_resource_track(ctx, NULL, &ctx->global_rtrack, ctx->fs->io);
> >
> > - ext2fs_close(fs);
> > - ctx->fs = NULL;
> > + ext2fs_close_free(&fs);
> > free(ctx->journal_name);
> >
> > e2fsck_free_context(ctx);
> > diff --git a/e2fsck/util.c b/e2fsck/util.c
> > index e7e8704..784577f 100644
> > --- a/e2fsck/util.c
> > +++ b/e2fsck/util.c
> > @@ -321,7 +321,7 @@ void preenhalt(e2fsck_t ctx)
> > if (fs != NULL) {
> > fs->super->s_state |= EXT2_ERROR_FS;
> > ext2fs_mark_super_dirty(fs);
> > - ext2fs_close(fs);
> > + ext2fs_close_free(&fs);
> > }
> > exit(FSCK_UNCORRECTED);
> > }
> > diff --git a/lib/ext2fs/closefs.c b/lib/ext2fs/closefs.c
> > index c2eaec1..e7ec0ae 100644
> > --- a/lib/ext2fs/closefs.c
> > +++ b/lib/ext2fs/closefs.c
> > @@ -450,6 +450,18 @@ errout:
> > return retval;
> > }
> >
> > +errcode_t ext2fs_close_free(ext2_filsys *fs_ptr)
> > +{
> > + errcode_t ret;
> > + ext2_filsys fs = *fs_ptr;
> > +
> > + ret = ext2fs_close2(fs, 0);
> > + if (ret)
> > + ext2fs_free(fs);
> > + *fs_ptr = NULL;
> > + return ret;
> > +}
> > +
> > errcode_t ext2fs_close(ext2_filsys fs)
> > {
> > return ext2fs_close2(fs, 0);
> > diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
> > index 7f7fd1f..253244d 100644
> > --- a/lib/ext2fs/ext2fs.h
> > +++ b/lib/ext2fs/ext2fs.h
> > @@ -945,6 +945,7 @@ extern errcode_t ext2fs_check_desc(ext2_filsys fs);
> > /* closefs.c */
> > extern errcode_t ext2fs_close(ext2_filsys fs);
> > extern errcode_t ext2fs_close2(ext2_filsys fs, int flags);
> > +extern errcode_t ext2fs_close_free(ext2_filsys *fs);
> > extern errcode_t ext2fs_flush(ext2_filsys fs);
> > extern errcode_t ext2fs_flush2(ext2_filsys fs, int flags);
> > extern int ext2fs_bg_has_super(ext2_filsys fs, dgrp_t group_block);
> > diff --git a/lib/ext2fs/mkjournal.c b/lib/ext2fs/mkjournal.c
> > index 884d9c0..2331e9e 100644
> > --- a/lib/ext2fs/mkjournal.c
> > +++ b/lib/ext2fs/mkjournal.c
> > @@ -642,7 +642,7 @@ main(int argc, char **argv)
> > if (retval) {
> > printf("Warning, had trouble writing out superblocks.\n");
> > }
> > - ext2fs_close(fs);
> > + ext2fs_close_free(&fs);
> > exit(0);
> >
> > }
> > diff --git a/lib/ext2fs/tst_bitmaps.c b/lib/ext2fs/tst_bitmaps.c
> > index 4e02ade..574fb7a 100644
> > --- a/lib/ext2fs/tst_bitmaps.c
> > +++ b/lib/ext2fs/tst_bitmaps.c
> > @@ -187,8 +187,7 @@ static void setup_filesystem(const char *name,
> > return;
> >
> > errout:
> > - ext2fs_close(test_fs);
> > - test_fs = 0;
> > + ext2fs_close_free(&test_fs);
> > }
> >
> > void setup_cmd(int argc, char **argv)
> > @@ -199,10 +198,8 @@ void setup_cmd(int argc, char **argv)
> > unsigned int type = EXT2FS_BMAP64_BITARRAY;
> > int flags = EXT2_FLAG_64BITS;
> >
> > - if (test_fs) {
> > - ext2fs_close(test_fs);
> > - test_fs = 0;
> > - }
> > + if (test_fs)
> > + ext2fs_close_free(&test_fs);
> >
> > reset_getopt();
> > while ((c = getopt(argc, argv, "b:i:lt:")) != EOF) {
> > @@ -242,8 +239,7 @@ void close_cmd(int argc, char **argv)
> > if (check_fs_open(argv[0]))
> > return;
> >
> > - ext2fs_close(test_fs);
> > - test_fs = 0;
> > + ext2fs_close_free(&test_fs);
> > }
> >
> >
> > diff --git a/misc/dumpe2fs.c b/misc/dumpe2fs.c
> > index ae54f8a..f2f62bf 100644
> > --- a/misc/dumpe2fs.c
> > +++ b/misc/dumpe2fs.c
> > @@ -651,7 +651,7 @@ int main (int argc, char ** argv)
> > if (fs->super->s_feature_incompat &
> > EXT3_FEATURE_INCOMPAT_JOURNAL_DEV) {
> > print_journal_information(fs);
> > - ext2fs_close(fs);
> > + ext2fs_close_free(&fs);
> > exit(0);
> > }
> > if ((fs->super->s_feature_compat &
> > @@ -660,7 +660,7 @@ int main (int argc, char ** argv)
> > print_inline_journal_information(fs);
> > list_bad_blocks(fs, 0);
> > if (header_only) {
> > - ext2fs_close (fs);
> > + ext2fs_close_free(&fs);
> > exit (0);
> > }
> > retval = ext2fs_read_bitmaps (fs);
> > @@ -671,7 +671,7 @@ int main (int argc, char ** argv)
> > error_message(retval));
> > }
> > }
> > - ext2fs_close (fs);
> > + ext2fs_close_free(&fs);
> > remove_error_table(&et_ext2_error_table);
> > exit (0);
> > }
> > diff --git a/misc/e2freefrag.c b/misc/e2freefrag.c
> > index 612ca44..bb72c70 100644
> > --- a/misc/e2freefrag.c
> > +++ b/misc/e2freefrag.c
> > @@ -215,7 +215,7 @@ static errcode_t get_chunk_info(ext2_filsys fs, struct chunk_info *info,
> >
> > static void close_device(char *device_name, ext2_filsys fs)
> > {
> > - int retval = ext2fs_close(fs);
> > + int retval = ext2fs_close_free(&fs);
> >
> > if (retval)
> > com_err(device_name, retval, "while closing the filesystem.\n");
> > diff --git a/misc/e2image.c b/misc/e2image.c
> > index b768826..f8457ab 100644
> > --- a/misc/e2image.c
> > +++ b/misc/e2image.c
> > @@ -1415,7 +1415,7 @@ static void install_image(char *device, char *image_fn, int type)
> > }
> >
> > close(fd);
> > - ext2fs_close (fs);
> > + ext2fs_close_free(&fs);
> > }
> >
> > static struct ext2_qcow2_hdr *check_qcow2_image(int *fd, char *name)
> > @@ -1648,7 +1648,7 @@ skip_device:
> > else
> > write_image_file(fs, fd);
> >
> > - ext2fs_close (fs);
> > + ext2fs_close_free(&fs);
> > if (check)
> > printf(_("%d blocks already contained the data to be copied.\n"),
> > skipped_blocks);
> > diff --git a/misc/e4defrag.c b/misc/e4defrag.c
> > index c2695e8..89bdfb9 100644
> > --- a/misc/e4defrag.c
> > +++ b/misc/e4defrag.c
> > @@ -1852,7 +1852,7 @@ int main(int argc, char *argv[])
> > feature_incompat = fs->super->s_feature_incompat;
> > log_groups_per_flex = fs->super->s_log_groups_per_flex;
> >
> > - ext2fs_close(fs);
> > + ext2fs_close_free(&fs);
> > }
> >
> > switch (arg_type) {
> > diff --git a/misc/mke2fs.c b/misc/mke2fs.c
> > index facbe4c..90c214e 100644
> > --- a/misc/mke2fs.c
> > +++ b/misc/mke2fs.c
> > @@ -1774,7 +1774,7 @@ profile_error:
> > printf(_("Using journal device's blocksize: %d\n"), blocksize);
> > fs_param.s_log_block_size =
> > int_log2(blocksize >> EXT2_MIN_BLOCK_LOG_SIZE);
> > - ext2fs_close(jfs);
> > + ext2fs_close_free(&jfs);
> > }
> >
> > if (optind < argc) {
> > @@ -2789,7 +2789,7 @@ int main (int argc, char *argv[])
> > if (fs->super->s_feature_incompat &
> > EXT3_FEATURE_INCOMPAT_JOURNAL_DEV) {
> > create_journal_dev(fs);
> > - exit(ext2fs_close(fs) ? 1 : 0);
> > + exit(ext2fs_close_free(&fs) ? 1 : 0);
> > }
> >
> > if (bad_blocks_filename)
> > @@ -2909,7 +2909,7 @@ int main (int argc, char *argv[])
> > }
> > if (!quiet)
> > printf("%s", _("done\n"));
> > - ext2fs_close(jfs);
> > + ext2fs_close_free(&jfs);
> > free(journal_device);
> > } else if ((journal_size) ||
> > (fs_param.s_feature_compat &
> > @@ -2973,7 +2973,7 @@ no_journal:
> > "filesystem accounting information: "));
> > checkinterval = fs->super->s_checkinterval;
> > max_mnt_count = fs->super->s_max_mnt_count;
> > - retval = ext2fs_close(fs);
> > + retval = ext2fs_close_free(&fs);
> > if (retval) {
> > fprintf(stderr, "%s",
> > _("\nWarning, had trouble writing out superblocks."));
> > diff --git a/misc/tune2fs.c b/misc/tune2fs.c
> > index 8ff47d2..c651d55 100644
> > --- a/misc/tune2fs.c
> > +++ b/misc/tune2fs.c
> > @@ -1205,7 +1205,7 @@ static int add_journal(ext2_filsys fs)
> > fflush(stdout);
> >
> > retval = ext2fs_add_journal_device(fs, jfs);
> > - ext2fs_close(jfs);
> > + ext2fs_close_free(&jfs);
> > if (retval) {
> > com_err(program_name, retval,
> > _("while adding filesystem to journal on %s"),
> > @@ -2512,7 +2512,7 @@ retry_open:
> > goto closefs;
> > }
> > if (io_ptr != io_ptr_orig) {
> > - ext2fs_close(fs);
> > + ext2fs_close_free(&fs);
> > goto retry_open;
> > }
> > }
> > @@ -2805,5 +2805,5 @@ closefs:
> > exit(1);
> > }
> >
> > - return (ext2fs_close(fs) ? 1 : 0);
> > + return (ext2fs_close_free(&fs) ? 1 : 0);
> > }
> > diff --git a/resize/main.c b/resize/main.c
> > index 2b7abff..c575220 100644
> > --- a/resize/main.c
> > +++ b/resize/main.c
> > @@ -468,7 +468,7 @@ int main (int argc, char ** argv)
> > _("Please run 'e2fsck -fy %s' to fix the filesystem\n"
> > "after the aborted resize operation.\n"),
> > device_name);
> > - ext2fs_close(fs);
> > + ext2fs_close_free(&fs);
> > exit(1);
> > }
> > printf(_("The filesystem on %s is now %llu blocks long.\n\n"),
> > diff --git a/resize/resize2fs.c b/resize/resize2fs.c
> > index 8353338..9a51733 100644
> > --- a/resize/resize2fs.c
> > +++ b/resize/resize2fs.c
> > @@ -202,7 +202,7 @@ errcode_t resize_fs(ext2_filsys fs, blk64_t *new_size, int flags,
> > rfs->new_fs->flags &= ~EXT2_FLAG_MASTER_SB_ONLY;
> >
> > print_resource_track(rfs, &overall_track, fs->io);
> > - retval = ext2fs_close(rfs->new_fs);
> > + retval = ext2fs_close_free(&rfs->new_fs);
> > if (retval)
> > goto errout;
> >
> > --
> > 1.8.3.1
> >
> > --
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