svn commit: r185587 - head/sbin/newfs_msdos
Luigi Rizzo
luigi at FreeBSD.org
Wed Dec 3 10:22:37 PST 2008
Author: luigi
Date: Wed Dec 3 18:22:36 2008
New Revision: 185587
URL: http://svn.freebsd.org/changeset/base/185587
Log:
Some useful operational extensions to newfs_msdos, especially
when preparing images for emulators or flash devices:
+ option '-C size' to create the underlying image file with given size.
Saves doing a 'dd' before, and especially it creates a sparse file
+ option '-@ offset' to build the FAT image at the specified offset
in the image file or device;
+ make the cluster size adaptive on the filesystem size.
Previously the default was 4k which is really unconvenient with
large media; now it goes from 512 bytes to 32k depending on
filesystem size (i still need to check whether it makes sense
to go further up, to 64k or above);
+ fix default geometry when not specified on the command line,
use 63 sectors/255 heads by default.
Also trim the size so it exactly a multiple of a track, to avoid
complaints in some filesystem code.
+ document all the above, plus some manual page clarifications.
MFC after: 4 weeks
Modified:
head/sbin/newfs_msdos/newfs_msdos.8
head/sbin/newfs_msdos/newfs_msdos.c
Modified: head/sbin/newfs_msdos/newfs_msdos.8
==============================================================================
--- head/sbin/newfs_msdos/newfs_msdos.8 Wed Dec 3 17:54:09 2008 (r185586)
+++ head/sbin/newfs_msdos/newfs_msdos.8 Wed Dec 3 18:22:36 2008 (r185587)
@@ -34,7 +34,9 @@
.Sh SYNOPSIS
.Nm
.Op Fl N
+.Op Fl @ Ar offset
.Op Fl B Ar boot
+.Op Fl C Ar create-size
.Op Fl F Ar FAT-type
.Op Fl I Ar volid
.Op Fl L Ar label
@@ -59,7 +61,7 @@
.Sh DESCRIPTION
The
.Nm
-utility creates a FAT12, FAT16, or FAT32 file system on device
+utility creates a FAT12, FAT16, or FAT32 file system on device or file named
.Ar special ,
using
.Xr disktab 5
@@ -67,16 +69,39 @@ entry
.Ar disktype
to determine geometry, if required.
.Pp
+If
+.Ar special
+does not contain a
+.Ar / ,
+it is assumed to be a device name and
+.Ar /dev
+is prepended to the name to construct the actual device name.
+To work a file in the current directory use
+.Ar ./filename
+.Pp
The options are as follow:
.Bl -tag -width indent
.It Fl N
Do not create a file system: just print out parameters.
+.It Fl @ Ar offset
+Build the filesystem at the specified offset in bytes in the device or file.
+A suffix s, k, m, g (lower or upper case)
+appended to the offset specifies that the
+number is in sectors, kilobytes, megabytes or gigabytes, respectively.
.It Fl B Ar boot
Get bootstrap from file.
+.It Fl C Ar create-size
+Create the image file with the specified size. A suffix character appended
+to the size is interpreted as for the
+.Fl @
+option. The file is created by truncating any existing file with the
+same name, seeking just before the required size and writing
+a single 0 byte. As a consequence, the space occupied on disk
+may be smaller than the size specified as a parameter.
.It Fl F Ar FAT-type
FAT type (one of 12, 16, or 32).
.It Fl I Ar volid
-Volume ID.
+Volume ID, a 32 bit number in decimal or hexadecimal (0x...) format.
.It Fl L Ar label
Volume label (up to 11 characters).
The label should consist of
@@ -99,6 +124,9 @@ acceptable number of sectors per cluster
Sectors per cluster.
Acceptable values are powers of 2 in the range
1 through 128.
+If the block or cluster size are not specified, the code
+uses a cluster between 512 bytes and 32K depending on
+the filesystem size.
.It Fl e Ar dirents
Number of root directory entries (FAT12 and FAT16 only).
.It Fl f Ar format
@@ -132,6 +160,15 @@ File system size.
Number of sectors per track.
.El
.Sh NOTES
+If some parameters (e.g. size, number of sectors, etc.) are not specified
+through options or disktype, the program tries to generate them
+automatically. In particular, the size is determined as the
+device or file size minus the offset specified with the
+.Fl @
+option. When the geometry is not available, it is assumed to be
+63 sectors, 255 heads. The size is then rounded to become
+a multiple of the track size and avoid complaints by some filesystem code.
+.Pp
FAT file system parameters occupy a "Boot Sector BPB (BIOS Parameter
Block)" in the first of the "reserved" sectors which precede the actual
file system.
@@ -167,20 +204,25 @@ The maximum file size is 4GB, even if th
.Sh EXIT STATUS
Exit status is 0 on success and 1 on error.
.Sh EXAMPLES
+Create a file system, using default parameters, on
+.Pa /dev/ad0s1 :
.Bd -literal -offset indent
newfs_msdos /dev/ad0s1
.Ed
.Pp
-Create a file system, using default parameters, on
-.Pa /dev/ad0s1 .
+Create a standard 1.44M file system, with volume label
+.Ar foo ,
+on
+.Pa /dev/fd0 :
.Bd -literal -offset indent
newfs_msdos -f 1440 -L foo fd0
.Ed
.Pp
-Create a standard 1.44M file system, with volume label
-.Ar foo ,
-on
-.Pa /dev/fd0 .
+Create a 30MB image file, with the FAT partition starting
+63 sectors within the image file:
+.Bd -literal -offset indent
+newfs_msdos -C 30M - at 63s ./somefile
+.Ed
.Sh SEE ALSO
.Xr disktab 5 ,
.Xr disklabel 8 ,
Modified: head/sbin/newfs_msdos/newfs_msdos.c
==============================================================================
--- head/sbin/newfs_msdos/newfs_msdos.c Wed Dec 3 17:54:09 2008 (r185586)
+++ head/sbin/newfs_msdos/newfs_msdos.c Wed Dec 3 18:22:36 2008 (r185587)
@@ -219,6 +219,7 @@ static void getdiskinfo(int, const char
static void print_bpb(struct bpb *);
static u_int ckgeom(const char *, u_int, const char *);
static u_int argtou(const char *, u_int, u_int, const char *);
+static off_t argtooff(const char *, const char *);
static int oklabel(const char *);
static void mklabel(u_int8_t *, const char *);
static void setstr(u_int8_t *, const char *, size_t);
@@ -230,7 +231,7 @@ static void usage(void);
int
main(int argc, char *argv[])
{
- static char opts[] = "NB:F:I:L:O:S:a:b:c:e:f:h:i:k:m:n:o:r:s:u:";
+ static char opts[] = "@:NB:C:F:I:L:O:S:a:b:c:e:f:h:i:k:m:n:o:r:s:u:";
static const char *opt_B, *opt_L, *opt_O, *opt_f;
static u_int opt_F, opt_I, opt_S, opt_a, opt_b, opt_c, opt_e;
static u_int opt_h, opt_i, opt_k, opt_m, opt_n, opt_o, opt_r;
@@ -253,15 +254,22 @@ main(int argc, char *argv[])
time_t now;
u_int fat, bss, rds, cls, dir, lsn, x, x1, x2;
int ch, fd, fd1;
+ static off_t opt_create=0, opt_ofs=0;
while ((ch = getopt(argc, argv, opts)) != -1)
switch (ch) {
+ case '@':
+ opt_ofs = argtooff(optarg, "offset");
+ break;
case 'N':
opt_N = 1;
break;
case 'B':
opt_B = optarg;
break;
+ case 'C':
+ opt_create = argtooff(optarg, "create size");
+ break;
case 'F':
if (strcmp(optarg, "12") &&
strcmp(optarg, "16") &&
@@ -346,13 +354,27 @@ main(int argc, char *argv[])
err(1, NULL);
}
dtype = *argv;
- if ((fd = open(fname, opt_N ? O_RDONLY : O_RDWR)) == -1 ||
+ if (opt_create) {
+ off_t pos;
+
+ if (opt_N)
+ errx(1, "create (-C) is incompatible with -N");
+ fd = open(fname, O_RDWR | O_CREAT | O_TRUNC, 0644);
+ if (fd == -1)
+ errx(1, "failed to create %s", fname);
+ pos = lseek(fd, opt_create - 1, SEEK_SET);
+ if (write(fd, "\0", 1) != 1)
+ errx(1, "failed to initialize %lld bytes", opt_create);
+ pos = lseek(fd, 0, SEEK_SET);
+ } else if ((fd = open(fname, opt_N ? O_RDONLY : O_RDWR)) == -1 ||
fstat(fd, &sb))
err(1, "%s", fname);
if (!opt_N)
check_mounted(fname, sb.st_mode);
if (!S_ISCHR(sb.st_mode))
- warnx("warning: %s is not a character device", fname);
+ warnx("warning, %s is not a character device", fname);
+ if (opt_ofs && opt_ofs != lseek(fd, opt_ofs, SEEK_SET))
+ errx(1, "cannot seek to %lld", opt_ofs);
memset(&bpb, 0, sizeof(bpb));
if (opt_f) {
getstdfmt(opt_f, &bpb);
@@ -371,8 +393,29 @@ main(int argc, char *argv[])
bpb.bsec = opt_s;
if (oflag)
bpb.hid = opt_o;
- if (!(opt_f || (opt_h && opt_u && opt_S && opt_s && oflag)))
+ if (!(opt_f || (opt_h && opt_u && opt_S && opt_s && oflag))) {
+ off_t delta;
getdiskinfo(fd, fname, dtype, oflag, &bpb);
+ bpb.bsec -= (opt_ofs / bpb.bps);
+ delta = bpb.bsec % bpb.spt;
+ if (delta != 0) {
+ warnx("trim %d sectors to adjust to a multiple of %d",
+ (int)delta, bpb.spt);
+ bpb.bsec -= delta;
+ }
+ if (bpb.spc == 0) { /* set defaults */
+ if (bpb.bsec <= 6000) /* about 3MB -> 512 bytes */
+ bpb.spc = 1;
+ else if (bpb.bsec <= (1<<17)) /* 64M -> 4k */
+ bpb.spc = 8;
+ else if (bpb.bsec <= (1<<19)) /* 256M -> 8k */
+ bpb.spc = 16;
+ else if (bpb.bsec <= (1<<21)) /* 1G -> 16k */
+ bpb.spc = 32;
+ else
+ bpb.spc = 64; /* otherwise 32k */
+ }
+ }
if (!powerof2(bpb.bps))
errx(1, "bytes/sector (%u) is not a power of 2", bpb.bps);
if (bpb.bps < MINBPS)
@@ -561,7 +604,7 @@ main(int argc, char *argv[])
fat == 32 && bpb.bkbs != MAXU16 &&
bss <= bpb.bkbs && x >= bpb.bkbs) {
x -= bpb.bkbs;
- if (!x && lseek(fd1, 0, SEEK_SET))
+ if (!x && lseek(fd1, opt_ofs, SEEK_SET))
err(1, "%s", bname);
}
if (opt_B && x < bss) {
@@ -728,14 +771,13 @@ getdiskinfo(int fd, const char *fname, c
if (ioctl(fd, DIOCGMEDIASIZE, &ms) == -1) {
struct stat st;
- bzero(&st, sizeof(st));
if (fstat(fd, &st))
err(1, "Cannot get disk size");
/* create a fake geometry for a file image */
ms = st.st_size;
dlp.d_secsize = 512;
- dlp.d_nsectors = 64;
- dlp.d_ntracks = 32;
+ dlp.d_nsectors = 63;
+ dlp.d_ntracks = 255;
dlp.d_secperunit = ms / dlp.d_secsize;
lp = &dlp;
} else if (ioctl(fd, FD_GTYPE, &type) != -1) {
@@ -833,6 +875,56 @@ argtou(const char *arg, u_int lo, u_int
}
/*
+ * Same for off_t, with optional skmgpP suffix
+ */
+static off_t
+argtooff(const char *arg, const char *msg)
+{
+ char *s;
+ off_t x;
+
+ x = strtoll(arg, &s, 0);
+ /* allow at most one extra char */
+ if (errno || x < 0 || (s[0] && s[1]) )
+ errx(1, "%s: bad %s", arg, msg);
+ if (*s) { /* the extra char is the multiplier */
+ switch (*s) {
+ default:
+ errx(1, "%s: bad %s", arg, msg);
+ /* notreached */
+
+ case 's': /* sector */
+ case 'S':
+ x <<= 9; /* times 512 */
+ break;
+
+ case 'k': /* kilobyte */
+ case 'K':
+ x <<= 10; /* times 1024 */
+ break;
+
+ case 'm': /* megabyte */
+ case 'M':
+ x <<= 20; /* times 1024*1024 */
+ break;
+
+ case 'g': /* gigabyte */
+ case 'G':
+ x <<= 30; /* times 1024*1024*1024 */
+ break;
+
+ case 'p': /* partition start */
+ case 'P': /* partition start */
+ case 'l': /* partition length */
+ case 'L': /* partition length */
+ errx(1, "%s: not supported yet %s", arg, msg);
+ /* notreached */
+ }
+ }
+ return x;
+}
+
+/*
* Check a volume label.
*/
static int
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