On Wed, Jan 20, 2021 at 01:26:26PM -0800, Harshad Shirwadkar wrote:
>
> - Fix compilation error by defining jbd2_journal_get_fc_num_blks (also
> rename it to jbd_get_fc_num_blks) as a preprocessor macro instead of
> inline function which gets compiled out when "-g" is passed
Unfortunately, this still doesn't quite fix things. The problem with
this approach is the preprocessor macro uses be32_to_cpu(), which gets
turned into ext2fs_swab32(). And the libe2p shared library is not
allowed to depend on libext2fs. Otherwise when we build with
configure --enable-elf-shlibs, the link of misc/chattr fails with:
<tytso@cwcc> {/build/e2fsprogs/misc}
1078% make V=1
../util/subst -f ../util/subst.conf /usr/projects/e2fsprogs/e2fsprogs/lib/dirpaths.h.in ../lib/dirpaths.h
gcc -Wl,-rpath-link,../lib -o chattr chattr.o ../lib/libe2p.so ../lib/libcom_err.so \
/bin/ld: ../lib/libe2p.so: undefined reference to `ext2fs_swab32'
collect2: error: ld returned 1 exit status
make: *** [Makefile:636: chattr] Error 1
We had already defined e2p_be32() and use it in other places in
lib/e2p/ljs.c.
So I fixed this by taking your Dec 10th version of the patch series,
and making the following change to patch 4/15:
diff --git a/lib/e2p/ljs.c b/lib/e2p/ljs.c
index 9f866c7e..59728198 100644
--- a/lib/e2p/ljs.c
+++ b/lib/e2p/ljs.c
@@ -36,6 +36,17 @@ static __u32 e2p_swab32(__u32 val)
#define e2p_be32(x) e2p_swab32(x)
#endif
+/*
+ * This function is copied from kernel-jbd.h's function
+ * jbd2_journal_get_num_fc_blks() to avoid inter-library dependencies.
+ */
+static inline int get_num_fc_blks(journal_superblock_t *jsb)
+{
+ int num_fc_blocks = e2p_be32(jsb->s_num_fc_blks);
+
+ return num_fc_blocks ? num_fc_blocks : JBD2_DEFAULT_FAST_COMMIT_BLOCKS;
+}
+
static const char *journal_checksum_type_str(__u8 type)
{
switch (type) {
@@ -58,7 +69,7 @@ void e2p_list_journal_super(FILE *f, char *journal_sb_buf,
int journal_blks = 0;
if (flags & E2P_LIST_JOURNAL_FLAG_FC)
- num_fc_blks = jbd2_journal_get_num_fc_blks((journal_superblock_t *)journal_sb_buf);
+ num_fc_blks = get_num_fc_blks((journal_superblock_t *)journal_sb_buf);
journal_blks = ntohl(jsb->s_maxlen) - num_fc_blks;
fprintf(f, "%s", "Journal features: ");
for (i=0, mask_ptr=&jsb->s_feature_compat; i <3; i++,mask_ptr++) {
