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Correct fsck journal-recovery code to update a cylinder-group

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check-hash after making changes to the cylinder group. The problem
was that the journal-recovery code was calling the libufs bwrite()
function instead of the cgput() function. The cgput() function updates
the cylinder-group check-hash before writing the cylinder group.

This change required the additions of the cgget() and cgput() functions
to the libufs API to avoid a gratuitous bcopy of every cylinder group
to be read or written. These new functions have been added to the
libufs manual pages. This was the first opportunity that I have had
to use and document the use of the EDOOFUS error code.

Reviewed by: kib
Reported by: emaste and others
This commit is contained in:
Kirk McKusick 2018-01-17 17:58:24 +00:00
parent 64e12b4140
commit 72f854ce8f
7 changed files with 161 additions and 51 deletions
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3
lib/libufs/Makefile
View File

@ -12,7 +12,10 @@ MAN= bread.3 cgread.3 libufs.3 sbread.3 ufs_disk_close.3
MLINKS+= bread.3 bwrite.3
MLINKS+= bread.3 berase.3
MLINKS+= cgread.3 cgread1.3
MLINKS+= cgread.3 cgget.3
MLINKS+= cgread.3 cgwrite.3
MLINKS+= cgread.3 cgwrite1.3
MLINKS+= cgread.3 cgput.3
MLINKS+= sbread.3 sbwrite.3
MLINKS+= ufs_disk_close.3 ufs_disk_fillout.3
MLINKS+= ufs_disk_close.3 ufs_disk_fillout_blank.3

120
lib/libufs/cgread.3
View File

@ -2,19 +2,22 @@
.\" Date: June 04, 2003
.\" Description:
.\" Manual page for libufs functions:
.\" cgget(3)
.\" cgput(3)
.\" cgread(3)
.\" cgread1(3)
.\" cgwrite(3)
.\" cgwrite1(3)
.\"
.\" This file is in the public domain.
.\"
.\" $FreeBSD$
.\"
.Dd June 4, 2003
.Dd January 19, 2018
.Dt CGREAD 3
.Os
.Sh NAME
.Nm cgread , cgread1, cgwrite1
.Nm cgget , cgput , cgread , cgread1 , cgwrite , cgwrite1
.Nd read/write cylinder groups of UFS disks
.Sh LIBRARY
.Lb libufs
@ -26,30 +29,72 @@
.In ufs/ffs/fs.h
.In libufs.h
.Ft int
.Fn cgget "struct uufsd *disk" "int cg" "struct cg *cgp"
.Ft int
.Fn cgput "struct uufsd *disk" "struct cg *cgp"
.Ft int
.Fn cgread "struct uufsd *disk"
.Ft int
.Fn cgread1 "struct uufsd *disk" "int c"
.Fn cgread1 "struct uufsd *disk" "int cg"
.Ft int
.Fn cgwrite1 "struct uufsd *disk" "int c"
.Fn cgwrite "struct uufsd *disk"
.Ft int
.Fn cgwrite1 "struct uufsd *disk" "int cg"
.Sh DESCRIPTION
The
.Fn cgread
.Fn cgget ,
.Fn cgread ,
and
.Fn cgread1
functions provide cylinder group reads for
.Xr libufs 3
consumers.
The
.Fn cgput ,
.Fn cgwrite ,
and
.Fn cgwrite1
functions provide cylinder group writes for
.Xr libufs 3
consumers.
.Pp
The
.Fn cgget
function reads the cylinder group specified by
.Fa cg
into the buffer pointed to by
.Fa cgp
from the disk referenced by the user-land UFS-disk structure.
The
.Fn cgget
function is the only cylinder group read function that is safe to use
in threaded applications.
.Pp
The
.Fn cgput
function writes the cylinder group specified by
.Va cgp
to the disk referenced by the user-land UFS-disk structure.
The
.Fn cgput
function is the only cylinder group write function that is safe to use
in threaded applications.
Note that the
.Fn cgput
function needs to be called only if the cylinder group has been
modified and the on-disk copy needs to be updated.
.Pp
The
.Fn cgread1
function reads from one cylinder group, specified by
.Fa c
function reads from the cylinder group specified by
.Fa cg
into the
.Va d_cg
field of a userland UFS disk structure.
cylinder-group structure in a user-land UFS-disk structure.
It sets the
.Va d_lcg
field to the cylinder group number
.Fa c .
.Fa cg .
.Pp
The
.Fn cgread
@ -65,34 +110,57 @@ field, and then incrementing the
field.
.Pp
The
.Fn cgwrite1
function stores cylinder group specified by
.Fa c
from
.Fn cgwrite
function stores on disk the cylinder group held in the
.Va d_cg
field of a userland UFS disk structure on disk.
cylinder-group structure in a user-land UFS-disk structure.
.Pp
The
.Fn cgwrite1
function provides no additional functionality over the
.Fn cgwrite
function as there is only one place that a given cylinder group
can correctly be written.
If the caller gets the
.Fa cg
parameter wrong, the function fails with the error
.Er EDOOFUS .
This function remains only to provide backward compatibility.
.Sh RETURN VALUES
Both functions return 0 if there are no more cylinder groups to read,
1 if there are more cylinder groups, and \-1 on error.
.Sh ERRORS
The function
The
.Fn cgread
may fail and set
function returns 0 if there are no more cylinder groups to read,
1 if there are more cylinder groups, and \-1 on error.
The
.Fn cgread1
function returns 1 on success and \-1 on error.
The other functions return 0 on success and \-1 on error;
.Sh ERRORS
The
.Fn cgget ,
.Fn cgread ,
and
.Fn cgread1
functions may fail and set
.Va errno
for any of the errors specified for the library function
.Xr bread 3 .
.Pp
The function
.Fn cgread1
has semantically identical failure conditions to those of
.Fn cgread .
.Pp
The function
The
.Fn cgput ,
.Fn cgwrite ,
and
.Fn cgwrite1
may fail and set
functions may fail and set
.Va errno
for any of the errors specified for the library function
.Xr bwrite 3 .
Additionally the
.Fn cgwrite1
will return the
.Er EDOOFUS
error if the cylinder group specified does not match the
cylinder group that it is requesting to write.
.Sh SEE ALSO
.Xr bread 3 ,
.Xr bwrite 3 ,

68
lib/libufs/cgroup.c
View File

@ -182,47 +182,85 @@ cgialloc(struct uufsd *disk)
int
cgread(struct uufsd *disk)
{
if (disk->d_ccg >= disk->d_fs.fs_ncg)
return (0);
return (cgread1(disk, disk->d_ccg++));
}
int
cgread1(struct uufsd *disk, int c)
{
if ((cgget(disk, c, &disk->d_cg)) == 0)
return (1);
return (-1);
}
int
cgget(struct uufsd *disk, int cg, struct cg *cgp)
{
struct fs *fs;
uint32_t cghash, calchash;
fs = &disk->d_fs;
if ((unsigned)c >= fs->fs_ncg) {
return (0);
}
if (bread(disk, fsbtodb(fs, cgtod(fs, c)), disk->d_cgunion.d_buf,
fs->fs_bsize) == -1) {
if (bread(disk, fsbtodb(fs, cgtod(fs, cg)), (void *)cgp,
fs->fs_cgsize) == -1) {
ERROR(disk, "unable to read cylinder group");
return (-1);
}
disk->d_lcg = c;
return (1);
calchash = cgp->cg_ckhash;
if ((fs->fs_metackhash & CK_CYLGRP) != 0) {
cghash = cgp->cg_ckhash;
cgp->cg_ckhash = 0;
calchash = calculate_crc32c(~0L, (void *)cgp, fs->fs_cgsize);
cgp->cg_ckhash = cghash;
}
if (cgp->cg_ckhash != calchash || !cg_chkmagic(cgp) ||
cgp->cg_cgx != cg) {
ERROR(disk, "cylinder group checks failed");
errno = EIO;
return (-1);
}
disk->d_lcg = cg;
return (0);
}
int
cgwrite(struct uufsd *disk)
{
return (cgwrite1(disk, disk->d_lcg));
return (cgput(disk, &disk->d_cg));
}
int
cgwrite1(struct uufsd *disk, int c)
cgwrite1(struct uufsd *disk, int cg)
{
static char errmsg[BUFSIZ];
if (cg == disk->d_cg.cg_cgx)
return (cgput(disk, &disk->d_cg));
snprintf(errmsg, BUFSIZ, "Cylinder group %d in buffer does not match "
"the cylinder group %d that cgwrite1 requested",
disk->d_cg.cg_cgx, cg);
ERROR(disk, errmsg);
errno = EDOOFUS;
return (-1);
}
int
cgput(struct uufsd *disk, struct cg *cgp)
{
struct fs *fs;
fs = &disk->d_fs;
if ((fs->fs_metackhash & CK_CYLGRP) != 0) {
disk->d_cg.cg_ckhash = 0;
disk->d_cg.cg_ckhash =
calculate_crc32c(~0L, (void *)&disk->d_cg, fs->fs_cgsize);
cgp->cg_ckhash = 0;
cgp->cg_ckhash =
calculate_crc32c(~0L, (void *)cgp, fs->fs_cgsize);
}
if (bwrite(disk, fsbtodb(fs, cgtod(fs, c)),
disk->d_cgunion.d_buf, fs->fs_bsize) == -1) {
if (bwrite(disk, fsbtodb(fs, cgtod(fs, cgp->cg_cgx)), cgp,
fs->fs_cgsize) == -1) {
ERROR(disk, "unable to write cylinder group");
return (-1);
}

5
lib/libufs/libufs.3
View File

@ -7,7 +7,7 @@
.\"
.\" $FreeBSD$
.\"
.Dd June 4, 2003
.Dd January 19, 2018
.Dt LIBUFS 3
.Os
.Sh NAME
@ -55,8 +55,11 @@ to a string describing the error.
.Sh SEE ALSO
.Xr bread 3 ,
.Xr bwrite 3 ,
.Xr cgget 3 ,
.Xr cgput 3 ,
.Xr cgread 3 ,
.Xr cgread1 3 ,
.Xr cgwrite 3 ,
.Xr cgwrite1 3 ,
.Xr sbread 3 ,
.Xr sbwrite 3 ,

2
lib/libufs/libufs.h
View File

@ -111,6 +111,8 @@ int berase(struct uufsd *, ufs2_daddr_t, ufs2_daddr_t);
ufs2_daddr_t cgballoc(struct uufsd *);
int cgbfree(struct uufsd *, ufs2_daddr_t, long);
ino_t cgialloc(struct uufsd *);
int cgget(struct uufsd *, int, struct cg *);
int cgput(struct uufsd *, struct cg *);
int cgread(struct uufsd *);
int cgread1(struct uufsd *, int);
int cgwrite(struct uufsd *);

11
sbin/fsck_ffs/gjournal.c
View File

@ -134,9 +134,8 @@ getcg(int cg)
if (cgc == NULL)
err(1, "malloc(%zu)", sizeof(*cgc));
}
if (cgread1(disk, cg) == -1)
err(1, "cgread1(%d)", cg);
bcopy(&disk->d_cg, &cgc->cgc_cg, sizeof(cgc->cgc_union));
if (cgget(disk, cg, &cgc->cgc_cg) == -1)
err(1, "cgget(%d)", cg);
cgc->cgc_busy = 0;
cgc->cgc_dirty = 0;
LIST_INSERT_HEAD(&cglist, cgc, cgc_next);
@ -191,10 +190,8 @@ putcgs(void)
LIST_REMOVE(cgc, cgc_next);
ncgs--;
if (cgc->cgc_dirty) {
bcopy(&cgc->cgc_cg, &disk->d_cg,
sizeof(cgc->cgc_union));
if (cgwrite1(disk, cgc->cgc_cg.cg_cgx) == -1)
err(1, "cgwrite1(%d)", cgc->cgc_cg.cg_cgx);
if (cgput(disk, &cgc->cgc_cg) == -1)
err(1, "cgput(%d)", cgc->cgc_cg.cg_cgx);
//printf("%s: Wrote cg=%d\n", __func__,
// cgc->cgc_cg.cg_cgx);
}

3
sbin/fsck_ffs/suj.c
View File

@ -1892,8 +1892,7 @@ cg_write(struct suj_cg *sc)
* before writing the block.
*/
fs->fs_cs(fs, sc->sc_cgx) = cgp->cg_cs;
if (bwrite(disk, fsbtodb(fs, cgtod(fs, sc->sc_cgx)), sc->sc_cgbuf,
fs->fs_bsize) == -1)
if (cgput(disk, cgp) == -1)
err_suj("Unable to write cylinder group %d\n", sc->sc_cgx);
}