1 files changed, 512 insertions, 0 deletions

diff --git a/fs/jfs/jfs_mount.c b/fs/jfs/jfs_mount.c
new file mode 100644
index 000000000000..c535ffd638e8
--- /dev/null
+++ b/fs/jfs/jfs_mount.c
@@ -0,0 +1,512 @@
+/*
+ *   Copyright (C) International Business Machines Corp., 2000-2004
+ *
+ *   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 of the License, 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+/*
+ * Module: jfs_mount.c
+ *
+ * note: file system in transition to aggregate/fileset:
+ *
+ * file system mount is interpreted as the mount of aggregate, 
+ * if not already mounted, and mount of the single/only fileset in 
+ * the aggregate;
+ *
+ * a file system/aggregate is represented by an internal inode
+ * (aka mount inode) initialized with aggregate superblock;
+ * each vfs represents a fileset, and points to its "fileset inode 
+ * allocation map inode" (aka fileset inode):
+ * (an aggregate itself is structured recursively as a filset: 
+ * an internal vfs is constructed and points to its "fileset inode 
+ * allocation map inode" (aka aggregate inode) where each inode 
+ * represents a fileset inode) so that inode number is mapped to 
+ * on-disk inode in uniform way at both aggregate and fileset level;
+ *
+ * each vnode/inode of a fileset is linked to its vfs (to facilitate
+ * per fileset inode operations, e.g., unmount of a fileset, etc.);
+ * each inode points to the mount inode (to facilitate access to
+ * per aggregate information, e.g., block size, etc.) as well as
+ * its file set inode.
+ *
+ *   aggregate 
+ *   ipmnt
+ *   mntvfs -> fileset ipimap+ -> aggregate ipbmap -> aggregate ipaimap;
+ *             fileset vfs     -> vp(1) <-> ... <-> vp(n) <->vproot;
+ */
+
+#include <linux/fs.h>
+#include <linux/buffer_head.h>
+
+#include "jfs_incore.h"
+#include "jfs_filsys.h"
+#include "jfs_superblock.h"
+#include "jfs_dmap.h"
+#include "jfs_imap.h"
+#include "jfs_metapage.h"
+#include "jfs_debug.h"
+
+
+/*
+ * forward references
+ */
+static int chkSuper(struct super_block *);
+static int logMOUNT(struct super_block *sb);
+
+/*
+ * NAME:        jfs_mount(sb)
+ *
+ * FUNCTION:    vfs_mount()
+ *
+ * PARAMETER:   sb      - super block
+ *
+ * RETURN:      -EBUSY  - device already mounted or open for write
+ *              -EBUSY  - cvrdvp already mounted;
+ *              -EBUSY  - mount table full
+ *              -ENOTDIR- cvrdvp not directory on a device mount
+ *              -ENXIO  - device open failure
+ */
+int jfs_mount(struct super_block *sb)
+{
+        int rc = 0;             /* Return code          */
+        struct jfs_sb_info *sbi = JFS_SBI(sb);
+        struct inode *ipaimap = NULL;
+        struct inode *ipaimap2 = NULL;
+        struct inode *ipimap = NULL;
+        struct inode *ipbmap = NULL;
+
+        /*
+         * read/validate superblock 
+         * (initialize mount inode from the superblock)
+         */
+        if ((rc = chkSuper(sb))) {
+                goto errout20;
+        }
+
+        ipaimap = diReadSpecial(sb, AGGREGATE_I, 0);
+        if (ipaimap == NULL) {
+                jfs_err("jfs_mount: Faild to read AGGREGATE_I");
+                rc = -EIO;
+                goto errout20;
+        }
+        sbi->ipaimap = ipaimap;
+
+        jfs_info("jfs_mount: ipaimap:0x%p", ipaimap);
+
+        /*
+         * initialize aggregate inode allocation map
+         */
+        if ((rc = diMount(ipaimap))) {
+                jfs_err("jfs_mount: diMount(ipaimap) failed w/rc = %d", rc);
+                goto errout21;
+        }
+
+        /*
+         * open aggregate block allocation map
+         */
+        ipbmap = diReadSpecial(sb, BMAP_I, 0);
+        if (ipbmap == NULL) {
+                rc = -EIO;
+                goto errout22;
+        }
+
+        jfs_info("jfs_mount: ipbmap:0x%p", ipbmap);
+
+        sbi->ipbmap = ipbmap;
+
+        /*
+         * initialize aggregate block allocation map
+         */
+        if ((rc = dbMount(ipbmap))) {
+                jfs_err("jfs_mount: dbMount failed w/rc = %d", rc);
+                goto errout22;
+        }
+
+        /*
+         * open the secondary aggregate inode allocation map
+         *
+         * This is a duplicate of the aggregate inode allocation map.
+         *
+         * hand craft a vfs in the same fashion as we did to read ipaimap.
+         * By adding INOSPEREXT (32) to the inode number, we are telling
+         * diReadSpecial that we are reading from the secondary aggregate
+         * inode table.  This also creates a unique entry in the inode hash
+         * table.
+         */
+        if ((sbi->mntflag & JFS_BAD_SAIT) == 0) {
+                ipaimap2 = diReadSpecial(sb, AGGREGATE_I, 1);
+                if (ipaimap2 == 0) {
+                        jfs_err("jfs_mount: Faild to read AGGREGATE_I");
+                        rc = -EIO;
+                        goto errout35;
+                }
+                sbi->ipaimap2 = ipaimap2;
+
+                jfs_info("jfs_mount: ipaimap2:0x%p", ipaimap2);
+
+                /*
+                 * initialize secondary aggregate inode allocation map
+                 */
+                if ((rc = diMount(ipaimap2))) {
+                        jfs_err("jfs_mount: diMount(ipaimap2) failed, rc = %d",
+                                rc);
+                        goto errout35;
+                }
+        } else
+                /* Secondary aggregate inode table is not valid */
+                sbi->ipaimap2 = NULL;
+
+        /*
+         *      mount (the only/single) fileset
+         */
+        /*
+         * open fileset inode allocation map (aka fileset inode)
+         */
+        ipimap = diReadSpecial(sb, FILESYSTEM_I, 0);
+        if (ipimap == NULL) {
+                jfs_err("jfs_mount: Failed to read FILESYSTEM_I");
+                /* open fileset secondary inode allocation map */
+                rc = -EIO;
+                goto errout40;
+        }
+        jfs_info("jfs_mount: ipimap:0x%p", ipimap);
+
+        /* map further access of per fileset inodes by the fileset inode */
+        sbi->ipimap = ipimap;
+
+        /* initialize fileset inode allocation map */
+        if ((rc = diMount(ipimap))) {
+                jfs_err("jfs_mount: diMount failed w/rc = %d", rc);
+                goto errout41;
+        }
+
+        goto out;
+
+        /*
+         *      unwind on error
+         */
+      errout41:         /* close fileset inode allocation map inode */
+        diFreeSpecial(ipimap);
+
+      errout40:         /* fileset closed */
+
+        /* close secondary aggregate inode allocation map */
+        if (ipaimap2) {
+                diUnmount(ipaimap2, 1);
+                diFreeSpecial(ipaimap2);
+        }
+
+      errout35:
+
+        /* close aggregate block allocation map */
+        dbUnmount(ipbmap, 1);
+        diFreeSpecial(ipbmap);
+
+      errout22:         /* close aggregate inode allocation map */
+
+        diUnmount(ipaimap, 1);
+
+      errout21:         /* close aggregate inodes */
+        diFreeSpecial(ipaimap);
+      errout20:         /* aggregate closed */
+
+      out:
+
+        if (rc)
+                jfs_err("Mount JFS Failure: %d", rc);
+
+        return rc;
+}
+
+/*
+ * NAME:        jfs_mount_rw(sb, remount)
+ *
+ * FUNCTION:    Completes read-write mount, or remounts read-only volume
+ *              as read-write
+ */
+int jfs_mount_rw(struct super_block *sb, int remount)
+{
+        struct jfs_sb_info *sbi = JFS_SBI(sb);  
+        int rc;
+
+        /*
+         * If we are re-mounting a previously read-only volume, we want to
+         * re-read the inode and block maps, since fsck.jfs may have updated
+         * them.
+         */
+        if (remount) {
+                if (chkSuper(sb) || (sbi->state != FM_CLEAN))
+                        return -EINVAL;
+
+                truncate_inode_pages(sbi->ipimap->i_mapping, 0);
+                truncate_inode_pages(sbi->ipbmap->i_mapping, 0);
+                diUnmount(sbi->ipimap, 1);
+                if ((rc = diMount(sbi->ipimap))) {
+                        jfs_err("jfs_mount_rw: diMount failed!");
+                        return rc;
+                }
+
+                dbUnmount(sbi->ipbmap, 1);
+                if ((rc = dbMount(sbi->ipbmap))) {
+                        jfs_err("jfs_mount_rw: dbMount failed!");
+                        return rc;
+                }
+        }
+
+        /*
+         * open/initialize log
+         */
+        if ((rc = lmLogOpen(sb)))
+                return rc;
+
+        /*
+         * update file system superblock;
+         */
+        if ((rc = updateSuper(sb, FM_MOUNT))) {
+                jfs_err("jfs_mount: updateSuper failed w/rc = %d", rc);
+                lmLogClose(sb);
+                return rc;
+        }
+
+        /*
+         * write MOUNT log record of the file system
+         */
+        logMOUNT(sb);
+
+        /*
+         * Set page cache allocation policy
+         */
+        mapping_set_gfp_mask(sb->s_bdev->bd_inode->i_mapping, GFP_NOFS);
+
+        return rc;
+}
+
+/*
+ *      chkSuper()
+ *
+ * validate the superblock of the file system to be mounted and 
+ * get the file system parameters.
+ *
+ * returns
+ *      0 with fragsize set if check successful
+ *      error code if not successful
+ */
+static int chkSuper(struct super_block *sb)
+{
+        int rc = 0;
+        struct jfs_sb_info *sbi = JFS_SBI(sb);
+        struct jfs_superblock *j_sb;
+        struct buffer_head *bh;
+        int AIM_bytesize, AIT_bytesize;
+        int expected_AIM_bytesize, expected_AIT_bytesize;
+        s64 AIM_byte_addr, AIT_byte_addr, fsckwsp_addr;
+        s64 byte_addr_diff0, byte_addr_diff1;
+        s32 bsize;
+
+        if ((rc = readSuper(sb, &bh)))
+                return rc;
+        j_sb = (struct jfs_superblock *)bh->b_data;
+
+        /*
+         * validate superblock
+         */
+        /* validate fs signature */
+        if (strncmp(j_sb->s_magic, JFS_MAGIC, 4) ||
+            le32_to_cpu(j_sb->s_version) > JFS_VERSION) {
+                rc = -EINVAL;
+                goto out;
+        }
+
+        bsize = le32_to_cpu(j_sb->s_bsize);
+#ifdef _JFS_4K
+        if (bsize != PSIZE) {
+                jfs_err("Currently only 4K block size supported!");
+                rc = -EINVAL;
+                goto out;
+        }
+#endif                          /* _JFS_4K */
+
+        jfs_info("superblock: flag:0x%08x state:0x%08x size:0x%Lx",
+                 le32_to_cpu(j_sb->s_flag), le32_to_cpu(j_sb->s_state),
+                 (unsigned long long) le64_to_cpu(j_sb->s_size));
+
+        /* validate the descriptors for Secondary AIM and AIT */
+        if ((j_sb->s_flag & cpu_to_le32(JFS_BAD_SAIT)) !=
+            cpu_to_le32(JFS_BAD_SAIT)) {
+                expected_AIM_bytesize = 2 * PSIZE;
+                AIM_bytesize = lengthPXD(&(j_sb->s_aim2)) * bsize;
+                expected_AIT_bytesize = 4 * PSIZE;
+                AIT_bytesize = lengthPXD(&(j_sb->s_ait2)) * bsize;
+                AIM_byte_addr = addressPXD(&(j_sb->s_aim2)) * bsize;
+                AIT_byte_addr = addressPXD(&(j_sb->s_ait2)) * bsize;
+                byte_addr_diff0 = AIT_byte_addr - AIM_byte_addr;
+                fsckwsp_addr = addressPXD(&(j_sb->s_fsckpxd)) * bsize;
+                byte_addr_diff1 = fsckwsp_addr - AIT_byte_addr;
+                if ((AIM_bytesize != expected_AIM_bytesize) ||
+                    (AIT_bytesize != expected_AIT_bytesize) ||
+                    (byte_addr_diff0 != AIM_bytesize) ||
+                    (byte_addr_diff1 <= AIT_bytesize))
+                        j_sb->s_flag |= cpu_to_le32(JFS_BAD_SAIT);
+        }
+
+        if ((j_sb->s_flag & cpu_to_le32(JFS_GROUPCOMMIT)) !=
+            cpu_to_le32(JFS_GROUPCOMMIT))
+                j_sb->s_flag |= cpu_to_le32(JFS_GROUPCOMMIT);
+
+        /* validate fs state */
+        if (j_sb->s_state != cpu_to_le32(FM_CLEAN) &&
+            !(sb->s_flags & MS_RDONLY)) {
+                jfs_err("jfs_mount: Mount Failure: File System Dirty.");
+                rc = -EINVAL;
+                goto out;
+        }
+
+        sbi->state = le32_to_cpu(j_sb->s_state);
+        sbi->mntflag = le32_to_cpu(j_sb->s_flag);
+
+        /*
+         * JFS always does I/O by 4K pages.  Don't tell the buffer cache
+         * that we use anything else (leave s_blocksize alone).
+         */
+        sbi->bsize = bsize;
+        sbi->l2bsize = le16_to_cpu(j_sb->s_l2bsize);
+
+        /*
+         * For now, ignore s_pbsize, l2bfactor.  All I/O going through buffer
+         * cache.
+         */
+        sbi->nbperpage = PSIZE >> sbi->l2bsize;
+        sbi->l2nbperpage = L2PSIZE - sbi->l2bsize;
+        sbi->l2niperblk = sbi->l2bsize - L2DISIZE;
+        if (sbi->mntflag & JFS_INLINELOG)
+                sbi->logpxd = j_sb->s_logpxd;
+        else {
+                sbi->logdev = new_decode_dev(le32_to_cpu(j_sb->s_logdev));
+                memcpy(sbi->uuid, j_sb->s_uuid, sizeof(sbi->uuid));
+                memcpy(sbi->loguuid, j_sb->s_loguuid, sizeof(sbi->uuid));
+        }
+        sbi->fsckpxd = j_sb->s_fsckpxd;
+        sbi->ait2 = j_sb->s_ait2;
+
+      out:
+        brelse(bh);
+        return rc;
+}
+
+
+/*
+ *      updateSuper()
+ *
+ * update synchronously superblock if it is mounted read-write.
+ */
+int updateSuper(struct super_block *sb, uint state)
+{
+        struct jfs_superblock *j_sb;
+        struct jfs_sb_info *sbi = JFS_SBI(sb);
+        struct buffer_head *bh;
+        int rc;
+
+        if (sbi->flag & JFS_NOINTEGRITY) {
+                if (state == FM_DIRTY) {
+                        sbi->p_state = state;
+                        return 0;
+                } else if (state == FM_MOUNT) {
+                        sbi->p_state = sbi->state;
+                        state = FM_DIRTY;
+                } else if (state == FM_CLEAN) {
+                        state = sbi->p_state;
+                } else
+                        jfs_err("updateSuper: bad state");
+        } else if (sbi->state == FM_DIRTY)
+                return 0;
+        
+        if ((rc = readSuper(sb, &bh)))
+                return rc;
+
+        j_sb = (struct jfs_superblock *)bh->b_data;
+
+        j_sb->s_state = cpu_to_le32(state);
+        sbi->state = state;
+
+        if (state == FM_MOUNT) {
+                /* record log's dev_t and mount serial number */
+                j_sb->s_logdev = cpu_to_le32(new_encode_dev(sbi->log->bdev->bd_dev));
+                j_sb->s_logserial = cpu_to_le32(sbi->log->serial);
+        } else if (state == FM_CLEAN) {
+                /*
+                 * If this volume is shared with OS/2, OS/2 will need to
+                 * recalculate DASD usage, since we don't deal with it.
+                 */
+                if (j_sb->s_flag & cpu_to_le32(JFS_DASD_ENABLED))
+                        j_sb->s_flag |= cpu_to_le32(JFS_DASD_PRIME);
+        }
+
+        mark_buffer_dirty(bh);
+        sync_dirty_buffer(bh);
+        brelse(bh);
+
+        return 0;
+}
+
+
+/*
+ *      readSuper()
+ *
+ * read superblock by raw sector address
+ */
+int readSuper(struct super_block *sb, struct buffer_head **bpp)
+{
+        /* read in primary superblock */
+        *bpp = sb_bread(sb, SUPER1_OFF >> sb->s_blocksize_bits);
+        if (*bpp)
+                return 0;
+
+        /* read in secondary/replicated superblock */
+        *bpp = sb_bread(sb, SUPER2_OFF >> sb->s_blocksize_bits);
+        if (*bpp)
+                return 0;
+
+        return -EIO;
+}
+
+
+/*
+ *      logMOUNT()
+ *
+ * function: write a MOUNT log record for file system.
+ *
+ * MOUNT record keeps logredo() from processing log records
+ * for this file system past this point in log.
+ * it is harmless if mount fails.
+ *
+ * note: MOUNT record is at aggregate level, not at fileset level, 
+ * since log records of previous mounts of a fileset
+ * (e.g., AFTER record of extent allocation) have to be processed 
+ * to update block allocation map at aggregate level.
+ */
+static int logMOUNT(struct super_block *sb)
+{
+        struct jfs_log *log = JFS_SBI(sb)->log;
+        struct lrd lrd;
+
+        lrd.logtid = 0;
+        lrd.backchain = 0;
+        lrd.type = cpu_to_le16(LOG_MOUNT);
+        lrd.length = 0;
+        lrd.aggregate = cpu_to_le32(new_encode_dev(sb->s_bdev->bd_dev));
+        lmLog(log, NULL, &lrd, NULL);
+
+        return 0;
+}