From e7f7fab95b2b37aa4498cadd4a3ccdd85eb192eb Mon Sep 17 00:00:00 2001 From: Miles Bader Date: Tue, 11 Apr 1995 21:48:12 +0000 Subject: Initial revision --- ext2fs/hyper.c | 193 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 193 insertions(+) create mode 100644 ext2fs/hyper.c (limited to 'ext2fs') diff --git a/ext2fs/hyper.c b/ext2fs/hyper.c new file mode 100644 index 00000000..8a556cef --- /dev/null +++ b/ext2fs/hyper.c @@ -0,0 +1,193 @@ +/* Fetching and storing the hypermetadata (superblock and cg summary info). + Copyright (C) 1994 Free Software Foundation + + This program is free software; you can redistribute it and/or + modify it under the terms of the GNU General Public License as + published by the Free Software Foundation; either version 2, or (at + your option) any later version. + + This program is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ + +#include "ufs.h" +#include +#include + +static int oldformat = 0; + +void +get_hypermetadata (void) +{ + sblock = malloc (SBSIZE); + + assert (!diskfs_catch_exception ()); + bcopy (disk_image + SBOFF, sblock, SBSIZE); + diskfs_end_catch_exception (); + + if (sblock->fs_magic != FS_MAGIC) + { + fprintf (stderr, "Bad magic number %#lx (should be %#x)\n", + sblock->fs_magic, FS_MAGIC); + exit (1); + } + if (sblock->fs_bsize > 8192) + { + fprintf (stderr, "Block size %ld is too big (max is 8192 bytes)\n", + sblock->fs_bsize); + exit (1); + } + if (sblock->fs_bsize < sizeof (struct fs)) + { + fprintf (stderr, "Block size %ld is too small (min is %ld bytes)\n", + sblock->fs_bsize, sizeof (struct fs)); + exit (1); + } + + if (sblock->fs_maxsymlinklen > (long)MAXSYMLINKLEN) + { + fprintf (stderr, "Max shortcut symlinklen %ld is too big (max is %ld)\n", + sblock->fs_maxsymlinklen, MAXSYMLINKLEN); + exit (1); + } + + assert ((__vm_page_size % DEV_BSIZE) == 0); + assert ((sblock->fs_bsize % DEV_BSIZE) == 0); + assert (__vm_page_size <= sblock->fs_bsize); + + /* If this is an old filesystem, then we have some more + work to do; some crucial constants might not be set; we + are therefore forced to set them here. */ + + if (sblock->fs_npsect < sblock->fs_nsect) + sblock->fs_npsect = sblock->fs_nsect; + + if (sblock->fs_interleave < 1) + sblock->fs_interleave = 1; + + if (sblock->fs_postblformat == FS_42POSTBLFMT) + sblock->fs_nrpos = 8; + + if (sblock->fs_inodefmt < FS_44INODEFMT) + { + quad_t sizepb = sblock->fs_bsize; + int i; + + oldformat = 1; + sblock->fs_maxfilesize = sblock->fs_bsize * NDADDR - 1; + for (i = 0; i < NIADDR; i++) + { + sizepb *= NINDIR (sblock); + sblock->fs_maxfilesize += sizepb; + } + sblock->fs_qbmask = ~sblock->fs_bmask; + sblock->fs_qfmask = ~sblock->fs_fmask; + } + + /* Find out if we support the 4.4 symlink/dirtype extension */ + if (sblock->fs_maxsymlinklen > 0) + direct_symlink_extension = 1; + else + direct_symlink_extension = 0; + + csum = malloc (fsaddr (sblock, howmany (sblock->fs_cssize, + sblock->fs_fsize))); + + assert (!diskfs_catch_exception ()); + bcopy (disk_image + fsaddr (sblock, sblock->fs_csaddr), + csum, + fsaddr (sblock, howmany (sblock->fs_cssize, sblock->fs_fsize))); + diskfs_end_catch_exception (); +} + +/* Write the csum data. This isn't backed by a pager because it is + taken from ordinary data blocks and might not be an even number + of pages; in that case writing it through the pager would nuke whatever + pages came after it on the disk and were backed by file pagers. */ +void +diskfs_set_hypermetadata (int wait, int clean) +{ + vm_address_t buf; + vm_size_t bufsize; + error_t err; + + spin_lock (&alloclock); + + if (!csum_dirty) + { + spin_unlock (&alloclock); + return; + } + + /* Copy into a page-aligned buffer to avoid bugs in kernel device code. */ + + bufsize = round_page (fragroundup (sblock, sblock->fs_cssize)); + + err = dev_read_sync (fsbtodb (sblock, sblock->fs_csaddr), &buf, bufsize); + if (!err) + { + bcopy (csum, (void *) buf, sblock->fs_cssize); + dev_write_sync (fsbtodb (sblock, sblock->fs_csaddr), buf, bufsize); + csum_dirty = 0; + vm_deallocate (mach_task_self (), buf, bufsize); + } + + spin_unlock (&alloclock); +} + +/* Copy the sblock into the disk */ +void +copy_sblock () +{ + int clean = 1; /* XXX wrong... */ + + assert (!diskfs_catch_exception ()); + + spin_lock (&alloclock); + + if (clean && !diskfs_readonly) + { + sblock->fs_clean = 1; + sblock_dirty = 1; + } + + if (sblock_dirty) + { + if (sblock->fs_postblformat == FS_42POSTBLFMT + || oldformat) + { + char sblockcopy[SBSIZE]; + struct fs *sbcopy = (struct fs *)sblockcopy; + bcopy (sblock, sblockcopy, SBSIZE); + if (sblock->fs_postblformat == FS_42POSTBLFMT) + sbcopy->fs_nrpos = -1; + if (oldformat) + { + sbcopy->fs_maxfilesize = -1; + sbcopy->fs_qbmask = -1; + sbcopy->fs_qfmask = -1; + } + bcopy (sbcopy, disk_image + SBOFF, SBSIZE); + } + else + bcopy (sblock, disk_image + SBOFF, SBSIZE); + record_poke (disk_image + SBOFF, SBSIZE); + sblock_dirty = 0; + } + + if (clean && !diskfs_readonly) + { + sblock->fs_clean = 0; + sblock_dirty = 1; + } + + spin_unlock (&alloclock); + diskfs_end_catch_exception (); +} + + -- cgit v1.2.3