1 files changed, 395 insertions, 0 deletions

diff --git a/fs/adfs/inode.c b/fs/adfs/inode.c
new file mode 100644
index 000000000000..a02802a30798
--- /dev/null
+++ b/fs/adfs/inode.c
@@ -0,0 +1,395 @@
+/*
+ *  linux/fs/adfs/inode.c
+ *
+ *  Copyright (C) 1997-1999 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/adfs_fs.h>
+#include <linux/time.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/smp_lock.h>
+#include <linux/module.h>
+#include <linux/buffer_head.h>
+
+#include "adfs.h"
+
+/*
+ * Lookup/Create a block at offset 'block' into 'inode'.  We currently do
+ * not support creation of new blocks, so we return -EIO for this case.
+ */
+static int
+adfs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh,
+               int create)
+{
+        if (block < 0)
+                goto abort_negative;
+
+        if (!create) {
+                if (block >= inode->i_blocks)
+                        goto abort_toobig;
+
+                block = __adfs_block_map(inode->i_sb, inode->i_ino, block);
+                if (block)
+                        map_bh(bh, inode->i_sb, block);
+                return 0;
+        }
+        /* don't support allocation of blocks yet */
+        return -EIO;
+
+abort_negative:
+        adfs_error(inode->i_sb, "block %d < 0", block);
+        return -EIO;
+
+abort_toobig:
+        return 0;
+}
+
+static int adfs_writepage(struct page *page, struct writeback_control *wbc)
+{
+        return block_write_full_page(page, adfs_get_block, wbc);
+}
+
+static int adfs_readpage(struct file *file, struct page *page)
+{
+        return block_read_full_page(page, adfs_get_block);
+}
+
+static int adfs_prepare_write(struct file *file, struct page *page, unsigned int from, unsigned int to)
+{
+        return cont_prepare_write(page, from, to, adfs_get_block,
+                &ADFS_I(page->mapping->host)->mmu_private);
+}
+
+static sector_t _adfs_bmap(struct address_space *mapping, sector_t block)
+{
+        return generic_block_bmap(mapping, block, adfs_get_block);
+}
+
+static struct address_space_operations adfs_aops = {
+        .readpage       = adfs_readpage,
+        .writepage      = adfs_writepage,
+        .sync_page      = block_sync_page,
+        .prepare_write  = adfs_prepare_write,
+        .commit_write   = generic_commit_write,
+        .bmap           = _adfs_bmap
+};
+
+static inline unsigned int
+adfs_filetype(struct inode *inode)
+{
+        unsigned int type;
+
+        if (ADFS_I(inode)->stamped)
+                type = (ADFS_I(inode)->loadaddr >> 8) & 0xfff;
+        else
+                type = (unsigned int) -1;
+
+        return type;
+}
+
+/*
+ * Convert ADFS attributes and filetype to Linux permission.
+ */
+static umode_t
+adfs_atts2mode(struct super_block *sb, struct inode *inode)
+{
+        unsigned int filetype, attr = ADFS_I(inode)->attr;
+        umode_t mode, rmask;
+        struct adfs_sb_info *asb = ADFS_SB(sb);
+
+        if (attr & ADFS_NDA_DIRECTORY) {
+                mode = S_IRUGO & asb->s_owner_mask;
+                return S_IFDIR | S_IXUGO | mode;
+        }
+
+        filetype = adfs_filetype(inode);
+
+        switch (filetype) {
+        case 0xfc0:     /* LinkFS */
+                return S_IFLNK|S_IRWXUGO;
+
+        case 0xfe6:     /* UnixExec */
+                rmask = S_IRUGO | S_IXUGO;
+                break;
+
+        default:
+                rmask = S_IRUGO;
+        }
+
+        mode = S_IFREG;
+
+        if (attr & ADFS_NDA_OWNER_READ)
+                mode |= rmask & asb->s_owner_mask;
+
+        if (attr & ADFS_NDA_OWNER_WRITE)
+                mode |= S_IWUGO & asb->s_owner_mask;
+
+        if (attr & ADFS_NDA_PUBLIC_READ)
+                mode |= rmask & asb->s_other_mask;
+
+        if (attr & ADFS_NDA_PUBLIC_WRITE)
+                mode |= S_IWUGO & asb->s_other_mask;
+        return mode;
+}
+
+/*
+ * Convert Linux permission to ADFS attribute.  We try to do the reverse
+ * of atts2mode, but there is not a 1:1 translation.
+ */
+static int
+adfs_mode2atts(struct super_block *sb, struct inode *inode)
+{
+        umode_t mode;
+        int attr;
+        struct adfs_sb_info *asb = ADFS_SB(sb);
+
+        /* FIXME: should we be able to alter a link? */
+        if (S_ISLNK(inode->i_mode))
+                return ADFS_I(inode)->attr;
+
+        if (S_ISDIR(inode->i_mode))
+                attr = ADFS_NDA_DIRECTORY;
+        else
+                attr = 0;
+
+        mode = inode->i_mode & asb->s_owner_mask;
+        if (mode & S_IRUGO)
+                attr |= ADFS_NDA_OWNER_READ;
+        if (mode & S_IWUGO)
+                attr |= ADFS_NDA_OWNER_WRITE;
+
+        mode = inode->i_mode & asb->s_other_mask;
+        mode &= ~asb->s_owner_mask;
+        if (mode & S_IRUGO)
+                attr |= ADFS_NDA_PUBLIC_READ;
+        if (mode & S_IWUGO)
+                attr |= ADFS_NDA_PUBLIC_WRITE;
+
+        return attr;
+}
+
+/*
+ * Convert an ADFS time to Unix time.  ADFS has a 40-bit centi-second time
+ * referenced to 1 Jan 1900 (til 2248)
+ */
+static void
+adfs_adfs2unix_time(struct timespec *tv, struct inode *inode)
+{
+        unsigned int high, low;
+
+        if (ADFS_I(inode)->stamped == 0)
+                goto cur_time;
+
+        high = ADFS_I(inode)->loadaddr << 24;
+        low  = ADFS_I(inode)->execaddr;
+
+        high |= low >> 8;
+        low  &= 255;
+
+        /* Files dated pre  01 Jan 1970 00:00:00. */
+        if (high < 0x336e996a)
+                goto too_early;
+
+        /* Files dated post 18 Jan 2038 03:14:05. */
+        if (high >= 0x656e9969)
+                goto too_late;
+
+        /* discard 2208988800 (0x336e996a00) seconds of time */
+        high -= 0x336e996a;
+
+        /* convert 40-bit centi-seconds to 32-bit seconds */
+        tv->tv_sec = (((high % 100) << 8) + low) / 100 + (high / 100 << 8);
+        tv->tv_nsec = 0;
+        return;
+
+ cur_time:
+        *tv = CURRENT_TIME_SEC;
+        return;
+
+ too_early:
+        tv->tv_sec = tv->tv_nsec = 0;
+        return;
+
+ too_late:
+        tv->tv_sec = 0x7ffffffd;
+        tv->tv_nsec = 0;
+        return;
+}
+
+/*
+ * Convert an Unix time to ADFS time.  We only do this if the entry has a
+ * time/date stamp already.
+ */
+static void
+adfs_unix2adfs_time(struct inode *inode, unsigned int secs)
+{
+        unsigned int high, low;
+
+        if (ADFS_I(inode)->stamped) {
+                /* convert 32-bit seconds to 40-bit centi-seconds */
+                low  = (secs & 255) * 100;
+                high = (secs / 256) * 100 + (low >> 8) + 0x336e996a;
+
+                ADFS_I(inode)->loadaddr = (high >> 24) |
+                                (ADFS_I(inode)->loadaddr & ~0xff);
+                ADFS_I(inode)->execaddr = (low & 255) | (high << 8);
+        }
+}
+
+/*
+ * Fill in the inode information from the object information.
+ *
+ * Note that this is an inode-less filesystem, so we can't use the inode
+ * number to reference the metadata on the media.  Instead, we use the
+ * inode number to hold the object ID, which in turn will tell us where
+ * the data is held.  We also save the parent object ID, and with these
+ * two, we can locate the metadata.
+ *
+ * This does mean that we rely on an objects parent remaining the same at
+ * all times - we cannot cope with a cross-directory rename (yet).
+ */
+struct inode *
+adfs_iget(struct super_block *sb, struct object_info *obj)
+{
+        struct inode *inode;
+
+        inode = new_inode(sb);
+        if (!inode)
+                goto out;
+
+        inode->i_uid     = ADFS_SB(sb)->s_uid;
+        inode->i_gid     = ADFS_SB(sb)->s_gid;
+        inode->i_ino     = obj->file_id;
+        inode->i_size    = obj->size;
+        inode->i_nlink   = 2;
+        inode->i_blksize = PAGE_SIZE;
+        inode->i_blocks  = (inode->i_size + sb->s_blocksize - 1) >>
+                            sb->s_blocksize_bits;
+
+        /*
+         * we need to save the parent directory ID so that
+         * write_inode can update the directory information
+         * for this file.  This will need special handling
+         * for cross-directory renames.
+         */
+        ADFS_I(inode)->parent_id = obj->parent_id;
+        ADFS_I(inode)->loadaddr  = obj->loadaddr;
+        ADFS_I(inode)->execaddr  = obj->execaddr;
+        ADFS_I(inode)->attr      = obj->attr;
+        ADFS_I(inode)->stamped    = ((obj->loadaddr & 0xfff00000) == 0xfff00000);
+
+        inode->i_mode    = adfs_atts2mode(sb, inode);
+        adfs_adfs2unix_time(&inode->i_mtime, inode);
+        inode->i_atime = inode->i_mtime;
+        inode->i_ctime = inode->i_mtime;
+
+        if (S_ISDIR(inode->i_mode)) {
+                inode->i_op     = &adfs_dir_inode_operations;
+                inode->i_fop    = &adfs_dir_operations;
+        } else if (S_ISREG(inode->i_mode)) {
+                inode->i_op     = &adfs_file_inode_operations;
+                inode->i_fop    = &adfs_file_operations;
+                inode->i_mapping->a_ops = &adfs_aops;
+                ADFS_I(inode)->mmu_private = inode->i_size;
+        }
+
+        insert_inode_hash(inode);
+
+out:
+        return inode;
+}
+
+/*
+ * Validate and convert a changed access mode/time to their ADFS equivalents.
+ * adfs_write_inode will actually write the information back to the directory
+ * later.
+ */
+int
+adfs_notify_change(struct dentry *dentry, struct iattr *attr)
+{
+        struct inode *inode = dentry->d_inode;
+        struct super_block *sb = inode->i_sb;
+        unsigned int ia_valid = attr->ia_valid;
+        int error;
+        
+        lock_kernel();
+
+        error = inode_change_ok(inode, attr);
+
+        /*
+         * we can't change the UID or GID of any file -
+         * we have a global UID/GID in the superblock
+         */
+        if ((ia_valid & ATTR_UID && attr->ia_uid != ADFS_SB(sb)->s_uid) ||
+            (ia_valid & ATTR_GID && attr->ia_gid != ADFS_SB(sb)->s_gid))
+                error = -EPERM;
+
+        if (error)
+                goto out;
+
+        if (ia_valid & ATTR_SIZE)
+                error = vmtruncate(inode, attr->ia_size);
+
+        if (error)
+                goto out;
+
+        if (ia_valid & ATTR_MTIME) {
+                inode->i_mtime = attr->ia_mtime;
+                adfs_unix2adfs_time(inode, attr->ia_mtime.tv_sec);
+        }
+        /*
+         * FIXME: should we make these == to i_mtime since we don't
+         * have the ability to represent them in our filesystem?
+         */
+        if (ia_valid & ATTR_ATIME)
+                inode->i_atime = attr->ia_atime;
+        if (ia_valid & ATTR_CTIME)
+                inode->i_ctime = attr->ia_ctime;
+        if (ia_valid & ATTR_MODE) {
+                ADFS_I(inode)->attr = adfs_mode2atts(sb, inode);
+                inode->i_mode = adfs_atts2mode(sb, inode);
+        }
+
+        /*
+         * FIXME: should we be marking this inode dirty even if
+         * we don't have any metadata to write back?
+         */
+        if (ia_valid & (ATTR_SIZE | ATTR_MTIME | ATTR_MODE))
+                mark_inode_dirty(inode);
+out:
+        unlock_kernel();
+        return error;
+}
+
+/*
+ * write an existing inode back to the directory, and therefore the disk.
+ * The adfs-specific inode data has already been updated by
+ * adfs_notify_change()
+ */
+int adfs_write_inode(struct inode *inode, int unused)
+{
+        struct super_block *sb = inode->i_sb;
+        struct object_info obj;
+        int ret;
+
+        lock_kernel();
+        obj.file_id     = inode->i_ino;
+        obj.name_len    = 0;
+        obj.parent_id   = ADFS_I(inode)->parent_id;
+        obj.loadaddr    = ADFS_I(inode)->loadaddr;
+        obj.execaddr    = ADFS_I(inode)->execaddr;
+        obj.attr        = ADFS_I(inode)->attr;
+        obj.size        = inode->i_size;
+
+        ret = adfs_dir_update(sb, &obj);
+        unlock_kernel();
+        return ret;
+}
+MODULE_LICENSE("GPL");