> On Aug 13, 2016, at 10:15 PM, Zorro Lang <zlang@xxxxxxxxxx> wrote: > >> On Fri, Aug 12, 2016 at 06:30:03PM -0500, Eric Sandeen wrote: >> This adds a new "crc" command to xfs_db for CRC-enabled filesystems. >> >> If a structure has a CRC field, we can validate it, invalidate/corrupt >> it, or revalidate/rewrite it: >> >> xfs_db> sb 0 >> xfs_db> crc -v >> crc = 0x796c814f (correct) >> xfs_db> crc -i >> Metadata CRC error detected at block 0x0/0x200 >> crc = 0x796c8150 (bad) >> xfs_db> crc -r >> crc = 0x796c814f (correct) >> >> (-i and -r require "expert" write-capable mode) >> >> This requires temporarily replacing the write verifier with >> a dummy which won't recalculate the CRC on the way to disk. >> >> It also required me to write a new flist function, which is >> totally foreign to me, so hopefully done right - but it seems >> to work here. >> >> Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx> >> --- >> >> I found this very useful when working with a filesystem image >> which was consistent except for a corrupt CRC; the ability to >> rewrite the correct CRCs and run repair to validate the fs was >> very handy... > > Hi Eric, > > I agree that this feature is very useful when some hardware or > software problems make a bad CRC value. But is this patch a completed > patch? > > For example, flist_find_ftyp is created by this patch, by I can't find > where is it called in this patch. > Argh somehow guilt did not pick up the new files. I will resend. Thanks, Eric > I checked your original V1 patch: > https://www.marc.info/?l=linux-xfs&m=142662442506252&w=3 > > It has more content than this. Should I read/merge this patch with > other patches together? > > Thanks, > Zorro > >> >> V2: Fix whitespace damage, clarify write_cur() changes >> a bit w/ code & comments. >> >> V3: Be a bit more verbose with command output >> >> V4: Rebase patch to current tree >> >> diff --git a/db/Makefile b/db/Makefile >> index 8260da3..ba4b1a8 100644 >> --- a/db/Makefile >> +++ b/db/Makefile >> @@ -8,7 +8,7 @@ include $(TOPDIR)/include/builddefs >> LTCOMMAND = xfs_db >> >> HFILES = addr.h agf.h agfl.h agi.h attr.h attrshort.h bit.h block.h bmap.h \ >> - btblock.h bmroot.h check.h command.h convert.h debug.h \ >> + btblock.h bmroot.h check.h command.h convert.h crc.h debug.h \ >> dir2.h dir2sf.h dquot.h echo.h faddr.h field.h \ >> flist.h fprint.h frag.h freesp.h hash.h help.h init.h inode.h input.h \ >> io.h logformat.h malloc.h metadump.h output.h print.h quit.h sb.h \ >> diff --git a/db/command.c b/db/command.c >> index 3c17a1e..1848d64 100644 >> --- a/db/command.c >> +++ b/db/command.c >> @@ -49,6 +49,7 @@ >> #include "write.h" >> #include "malloc.h" >> #include "dquot.h" >> +#include "crc.h" >> >> cmdinfo_t *cmdtab; >> int ncmds; >> @@ -124,6 +125,7 @@ init_commands(void) >> bmap_init(); >> check_init(); >> convert_init(); >> + crc_init(); >> debug_init(); >> echo_init(); >> frag_init(); >> diff --git a/db/flist.c b/db/flist.c >> index 84065a2..2530baf 100644 >> --- a/db/flist.c >> +++ b/db/flist.c >> @@ -411,6 +411,40 @@ flist_split( >> return v; >> } >> >> +/* >> + * Given a set of fields, scan for a field of the given type. >> + * Return an flist leading to the first found field >> + * of that type. >> + * Return NULL if no field of the given type is found. >> + */ >> +flist_t * >> +flist_find_ftyp( >> + const field_t *fields, >> + fldt_t type) >> +{ >> + flist_t *fl; >> + const field_t *f; >> + const ftattr_t *fa; >> + >> + for (f = fields; f->name; f++) { >> + fl = flist_make(f->name); >> + fl->fld = f; >> + if (f->ftyp == type) >> + return fl; >> + fa = &ftattrtab[f->ftyp]; >> + if (fa->subfld) { >> + flist_t *nfl; >> + nfl = flist_find_ftyp(fa->subfld, type); >> + if (nfl) { >> + fl->child = nfl; >> + return fl; >> + } >> + } >> + flist_free(fl); >> + } >> + return NULL; >> +} >> + >> static void >> ftok_free( >> ftok_t *ft) >> diff --git a/db/flist.h b/db/flist.h >> index 5c9fba0..3f4b312 100644 >> --- a/db/flist.h >> +++ b/db/flist.h >> @@ -37,3 +37,4 @@ extern int flist_parse(const struct field *fields, flist_t *fl, void *obj, >> int startoff); >> extern void flist_print(flist_t *fl); >> extern flist_t *flist_scan(char *name); >> +extern flist_t *flist_find_ftyp(const field_t *fields, fldt_t type); >> diff --git a/db/io.c b/db/io.c >> index 91cab12..56b4414 100644 >> --- a/db/io.c >> +++ b/db/io.c >> @@ -27,6 +27,7 @@ >> #include "output.h" >> #include "init.h" >> #include "malloc.h" >> +#include "crc.h" >> >> static int pop_f(int argc, char **argv); >> static void pop_help(void); >> @@ -473,12 +474,14 @@ xfs_verify_recalc_crc( >> void >> write_cur(void) >> { >> + int skip_crc = (iocur_top->bp->b_ops->verify_write == xfs_dummy_verify); >> + >> if (iocur_sp < 0) { >> dbprintf(_("nothing to write\n")); >> return; >> } >> >> - if (xfs_sb_version_hascrc(&mp->m_sb) && iocur_top->ino_buf) { >> + if (xfs_sb_version_hascrc(&mp->m_sb) && iocur_top->ino_buf && !skip_crc) { >> libxfs_dinode_calc_crc(mp, iocur_top->data); >> iocur_top->ino_crc_ok = 1; >> } >> @@ -489,6 +492,19 @@ write_cur(void) >> write_cur_bbs(); >> else >> write_cur_buf(); >> + >> + /* If we didn't write the crc automatically, re-check validity */ >> + if (iocur_top->ino_buf && skip_crc) { >> + xfs_dinode_t *dip; >> + xfs_ino_t ino; >> + >> + dip = iocur_top->data; >> + ino = iocur_top->ino; >> + iocur_top->ino_crc_ok = xfs_verify_cksum((char *)dip, >> + mp->m_sb.sb_inodesize, >> + XFS_DINODE_CRC_OFF); >> + } >> + >> } >> >> void >> diff --git a/db/write.h b/db/write.h >> index 31e2665..664ddcc 100644 >> --- a/db/write.h >> +++ b/db/write.h >> @@ -20,5 +20,5 @@ struct field; >> >> extern void write_init(void); >> extern void write_block(const field_t *fields, int argc, char **argv); >> -extern void write_string(const field_t *fields, int argc, char **argv); >> extern void write_struct(const field_t *fields, int argc, char **argv); >> +extern void write_string(const field_t *fields, int argc, char **argv); >> diff --git a/man/man8/xfs_db.8 b/man/man8/xfs_db.8 >> index ff8f862..894a94e 100644 >> --- a/man/man8/xfs_db.8 >> +++ b/man/man8/xfs_db.8 >> @@ -87,16 +87,14 @@ or >> .I filename >> read-only. This option is required if the filesystem is mounted. >> It is only necessary to omit this flag if a command that changes data >> -.RB ( write ", " blocktrash ) >> +.RB ( write ", " blocktrash ", " crc ) >> is to be used. >> .TP >> .B \-x >> Specifies expert mode. >> This enables the >> -.B write >> -and >> -.B blocktrash >> -commands. >> +.RB ( write ", " blocktrash ", " crc >> +invalidate/revalidate) commands. >> .TP >> .B \-V >> Prints the version number and exits. >> @@ -422,6 +420,25 @@ conversions such as >> .I agb >> .BR fsblock . >> .TP >> +.B crc [\-i|\-r|\-v] >> +Invalidates, revalidates, or validates the CRC (checksum) >> +field of the current structure, if it has one. >> +This command is available only on CRC-enabled filesystems. >> +With no argument, validation is performed. >> +Each command will display the resulting CRC value and state. >> +.RS 1.0i >> +.TP 0.4i >> +.B \-i >> +Invalidate the structure's CRC value (incrementing it by one), >> +and write it to disk. >> +.TP >> +.B \-r >> +Recalculate the current structure's correct CRC value, and write it to disk. >> +.TP >> +.B \-v >> +Validate and display the current value and state of the structure's CRC. >> +.RE >> +.TP >> .BI "daddr [" d ] >> Set current address to the daddr (512 byte block) given by >> .IR d . >> >> _______________________________________________ >> xfs mailing list >> xfs@xxxxxxxxxxx >> http://oss.sgi.com/mailman/listinfo/xfs > > _______________________________________________ > xfs mailing list > xfs@xxxxxxxxxxx > http://oss.sgi.com/mailman/listinfo/xfs > _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
