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root/fs/affs/inode.c

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DEFINITIONS

This source file includes following definitions.
  1. affs_iget
  2. affs_write_inode
  3. affs_notify_change
  4. affs_delete_inode
  5. affs_clear_inode
  6. affs_new_inode
  7. affs_add_entry

/*
 *  linux/fs/affs/inode.c
 *
 *  (c) 1996  Hans-Joachim Widmaier - Rewritten
 *
 *  (C) 1993  Ray Burr - Modified for Amiga FFS filesystem.
 *
 *  (C) 1992  Eric Youngdale Modified for ISO9660 filesystem.
 *
 *  (C) 1991  Linus Torvalds - minix filesystem
 */
#include <linux/sched.h>
#include "affs.h"

extern const struct inode_operations affs_symlink_inode_operations;
extern struct timezone sys_tz;

struct inode *affs_iget(struct super_block *sb, unsigned long ino)
{
        struct affs_sb_info     *sbi = AFFS_SB(sb);
        struct buffer_head      *bh;
        struct affs_head        *head;
        struct affs_tail        *tail;
        struct inode            *inode;
        u32                      block;
        u32                      size;
        u32                      prot;
        u16                      id;

        inode = iget_locked(sb, ino);
        if (!inode)
                return ERR_PTR(-ENOMEM);
        if (!(inode->i_state & I_NEW))
                return inode;

        pr_debug("AFFS: affs_iget(%lu)\n", inode->i_ino);

        block = inode->i_ino;
        bh = affs_bread(sb, block);
        if (!bh) {
                affs_warning(sb, "read_inode", "Cannot read block %d", block);
                goto bad_inode;
        }
        if (affs_checksum_block(sb, bh) || be32_to_cpu(AFFS_HEAD(bh)->ptype) != T_SHORT) {
                affs_warning(sb,"read_inode",
                           "Checksum or type (ptype=%d) error on inode %d",
                           AFFS_HEAD(bh)->ptype, block);
                goto bad_inode;
        }

        head = AFFS_HEAD(bh);
        tail = AFFS_TAIL(sb, bh);
        prot = be32_to_cpu(tail->protect);

        inode->i_size = 0;
        inode->i_nlink = 1;
        inode->i_mode = 0;
        AFFS_I(inode)->i_extcnt = 1;
        AFFS_I(inode)->i_ext_last = ~1;
        AFFS_I(inode)->i_protect = prot;
        atomic_set(&AFFS_I(inode)->i_opencnt, 0);
        AFFS_I(inode)->i_blkcnt = 0;
        AFFS_I(inode)->i_lc = NULL;
        AFFS_I(inode)->i_lc_size = 0;
        AFFS_I(inode)->i_lc_shift = 0;
        AFFS_I(inode)->i_lc_mask = 0;
        AFFS_I(inode)->i_ac = NULL;
        AFFS_I(inode)->i_ext_bh = NULL;
        AFFS_I(inode)->mmu_private = 0;
        AFFS_I(inode)->i_lastalloc = 0;
        AFFS_I(inode)->i_pa_cnt = 0;

        if (sbi->s_flags & SF_SETMODE)
                inode->i_mode = sbi->s_mode;
        else
                inode->i_mode = prot_to_mode(prot);

        id = be16_to_cpu(tail->uid);
        if (id == 0 || sbi->s_flags & SF_SETUID)
                inode->i_uid = sbi->s_uid;
        else if (id == 0xFFFF && sbi->s_flags & SF_MUFS)
                inode->i_uid = 0;
        else
                inode->i_uid = id;

        id = be16_to_cpu(tail->gid);
        if (id == 0 || sbi->s_flags & SF_SETGID)
                inode->i_gid = sbi->s_gid;
        else if (id == 0xFFFF && sbi->s_flags & SF_MUFS)
                inode->i_gid = 0;
        else
                inode->i_gid = id;

        switch (be32_to_cpu(tail->stype)) {
        case ST_ROOT:
                inode->i_uid = sbi->s_uid;
                inode->i_gid = sbi->s_gid;
                /* fall through */
        case ST_USERDIR:
                if (be32_to_cpu(tail->stype) == ST_USERDIR ||
                    sbi->s_flags & SF_SETMODE) {
                        if (inode->i_mode & S_IRUSR)
                                inode->i_mode |= S_IXUSR;
                        if (inode->i_mode & S_IRGRP)
                                inode->i_mode |= S_IXGRP;
                        if (inode->i_mode & S_IROTH)
                                inode->i_mode |= S_IXOTH;
                        inode->i_mode |= S_IFDIR;
                } else
                        inode->i_mode = S_IRUGO | S_IXUGO | S_IWUSR | S_IFDIR;
                /* Maybe it should be controlled by mount parameter? */
                //inode->i_mode |= S_ISVTX;
                inode->i_op = &affs_dir_inode_operations;
                inode->i_fop = &affs_dir_operations;
                break;
        case ST_LINKDIR:
#if 0
                affs_warning(sb, "read_inode", "inode is LINKDIR");
                goto bad_inode;
#else
                inode->i_mode |= S_IFDIR;
                inode->i_op = NULL;
                inode->i_fop = NULL;
                break;
#endif
        case ST_LINKFILE:
                affs_warning(sb, "read_inode", "inode is LINKFILE");
                goto bad_inode;
        case ST_FILE:
                size = be32_to_cpu(tail->size);
                inode->i_mode |= S_IFREG;
                AFFS_I(inode)->mmu_private = inode->i_size = size;
                if (inode->i_size) {
                        AFFS_I(inode)->i_blkcnt = (size - 1) /
                                               sbi->s_data_blksize + 1;
                        AFFS_I(inode)->i_extcnt = (AFFS_I(inode)->i_blkcnt - 1) /
                                               sbi->s_hashsize + 1;
                }
                if (tail->link_chain)
                        inode->i_nlink = 2;
                inode->i_mapping->a_ops = (sbi->s_flags & SF_OFS) ? &affs_aops_ofs : &affs_aops;
                inode->i_op = &affs_file_inode_operations;
                inode->i_fop = &affs_file_operations;
                break;
        case ST_SOFTLINK:
                inode->i_mode |= S_IFLNK;
                inode->i_op = &affs_symlink_inode_operations;
                inode->i_data.a_ops = &affs_symlink_aops;
                break;
        }

        inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec
                       = (be32_to_cpu(tail->change.days) * (24 * 60 * 60) +
                         be32_to_cpu(tail->change.mins) * 60 +
                         be32_to_cpu(tail->change.ticks) / 50 +
                         ((8 * 365 + 2) * 24 * 60 * 60)) +
                         sys_tz.tz_minuteswest * 60;
        inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = inode->i_atime.tv_nsec = 0;
        affs_brelse(bh);
        unlock_new_inode(inode);
        return inode;

bad_inode:
        affs_brelse(bh);
        iget_failed(inode);
        return ERR_PTR(-EIO);
}

int
affs_write_inode(struct inode *inode, int unused)
{
        struct super_block      *sb = inode->i_sb;
        struct buffer_head      *bh;
        struct affs_tail        *tail;
        uid_t                    uid;
        gid_t                    gid;

        pr_debug("AFFS: write_inode(%lu)\n",inode->i_ino);

        if (!inode->i_nlink)
                // possibly free block
                return 0;
        bh = affs_bread(sb, inode->i_ino);
        if (!bh) {
                affs_error(sb,"write_inode","Cannot read block %lu",inode->i_ino);
                return -EIO;
        }
        tail = AFFS_TAIL(sb, bh);
        if (tail->stype == cpu_to_be32(ST_ROOT)) {
                secs_to_datestamp(inode->i_mtime.tv_sec,&AFFS_ROOT_TAIL(sb, bh)->root_change);
        } else {
                tail->protect = cpu_to_be32(AFFS_I(inode)->i_protect);
                tail->size = cpu_to_be32(inode->i_size);
                secs_to_datestamp(inode->i_mtime.tv_sec,&tail->change);
                if (!(inode->i_ino == AFFS_SB(sb)->s_root_block)) {
                        uid = inode->i_uid;
                        gid = inode->i_gid;
                        if (AFFS_SB(sb)->s_flags & SF_MUFS) {
                                if (inode->i_uid == 0 || inode->i_uid == 0xFFFF)
                                        uid = inode->i_uid ^ ~0;
                                if (inode->i_gid == 0 || inode->i_gid == 0xFFFF)
                                        gid = inode->i_gid ^ ~0;
                        }
                        if (!(AFFS_SB(sb)->s_flags & SF_SETUID))
                                tail->uid = cpu_to_be16(uid);
                        if (!(AFFS_SB(sb)->s_flags & SF_SETGID))
                                tail->gid = cpu_to_be16(gid);
                }
        }
        affs_fix_checksum(sb, bh);
        mark_buffer_dirty_inode(bh, inode);
        affs_brelse(bh);
        affs_free_prealloc(inode);
        return 0;
}

int
affs_notify_change(struct dentry *dentry, struct iattr *attr)
{
        struct inode *inode = dentry->d_inode;
        int error;

        pr_debug("AFFS: notify_change(%lu,0x%x)\n",inode->i_ino,attr->ia_valid);

        error = inode_change_ok(inode,attr);
        if (error)
                goto out;

        if (((attr->ia_valid & ATTR_UID) && (AFFS_SB(inode->i_sb)->s_flags & SF_SETUID)) ||
            ((attr->ia_valid & ATTR_GID) && (AFFS_SB(inode->i_sb)->s_flags & SF_SETGID)) ||
            ((attr->ia_valid & ATTR_MODE) &&
             (AFFS_SB(inode->i_sb)->s_flags & (SF_SETMODE | SF_IMMUTABLE)))) {
                if (!(AFFS_SB(inode->i_sb)->s_flags & SF_QUIET))
                        error = -EPERM;
                goto out;
        }

        error = inode_setattr(inode, attr);
        if (!error && (attr->ia_valid & ATTR_MODE))
                mode_to_prot(inode);
out:
        return error;
}

void
affs_delete_inode(struct inode *inode)
{
        pr_debug("AFFS: delete_inode(ino=%lu, nlink=%u)\n", inode->i_ino, inode->i_nlink);
        truncate_inode_pages(&inode->i_data, 0);
        inode->i_size = 0;
        affs_truncate(inode);
        clear_inode(inode);
        affs_free_block(inode->i_sb, inode->i_ino);
}

void
affs_clear_inode(struct inode *inode)
{
        unsigned long cache_page;

        pr_debug("AFFS: clear_inode(ino=%lu, nlink=%u)\n", inode->i_ino, inode->i_nlink);

        affs_free_prealloc(inode);
        cache_page = (unsigned long)AFFS_I(inode)->i_lc;
        if (cache_page) {
                pr_debug("AFFS: freeing ext cache\n");
                AFFS_I(inode)->i_lc = NULL;
                AFFS_I(inode)->i_ac = NULL;
                free_page(cache_page);
        }
        affs_brelse(AFFS_I(inode)->i_ext_bh);
        AFFS_I(inode)->i_ext_last = ~1;
        AFFS_I(inode)->i_ext_bh = NULL;
}

struct inode *
affs_new_inode(struct inode *dir)
{
        struct super_block      *sb = dir->i_sb;
        struct inode            *inode;
        u32                      block;
        struct buffer_head      *bh;

        if (!(inode = new_inode(sb)))
                goto err_inode;

        if (!(block = affs_alloc_block(dir, dir->i_ino)))
                goto err_block;

        bh = affs_getzeroblk(sb, block);
        if (!bh)
                goto err_bh;
        mark_buffer_dirty_inode(bh, inode);
        affs_brelse(bh);

        inode->i_uid     = current->fsuid;
        inode->i_gid     = current->fsgid;
        inode->i_ino     = block;
        inode->i_nlink   = 1;
        inode->i_mtime   = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
        atomic_set(&AFFS_I(inode)->i_opencnt, 0);
        AFFS_I(inode)->i_blkcnt = 0;
        AFFS_I(inode)->i_lc = NULL;
        AFFS_I(inode)->i_lc_size = 0;
        AFFS_I(inode)->i_lc_shift = 0;
        AFFS_I(inode)->i_lc_mask = 0;
        AFFS_I(inode)->i_ac = NULL;
        AFFS_I(inode)->i_ext_bh = NULL;
        AFFS_I(inode)->mmu_private = 0;
        AFFS_I(inode)->i_protect = 0;
        AFFS_I(inode)->i_lastalloc = 0;
        AFFS_I(inode)->i_pa_cnt = 0;
        AFFS_I(inode)->i_extcnt = 1;
        AFFS_I(inode)->i_ext_last = ~1;

        insert_inode_hash(inode);

        return inode;

err_bh:
        affs_free_block(sb, block);
err_block:
        iput(inode);
err_inode:
        return NULL;
}

/*
 * Add an entry to a directory. Create the header block
 * and insert it into the hash table.
 */

int
affs_add_entry(struct inode *dir, struct inode *inode, struct dentry *dentry, s32 type)
{
        struct super_block *sb = dir->i_sb;
        struct buffer_head *inode_bh = NULL;
        struct buffer_head *bh = NULL;
        u32 block = 0;
        int retval;

        pr_debug("AFFS: add_entry(dir=%u, inode=%u, \"%*s\", type=%d)\n", (u32)dir->i_ino,
                 (u32)inode->i_ino, (int)dentry->d_name.len, dentry->d_name.name, type);

        retval = -EIO;
        bh = affs_bread(sb, inode->i_ino);
        if (!bh)
                goto done;

        affs_lock_link(inode);
        switch (type) {
        case ST_LINKFILE:
        case ST_LINKDIR:
                retval = -ENOSPC;
                block = affs_alloc_block(dir, dir->i_ino);
                if (!block)
                        goto err;
                retval = -EIO;
                inode_bh = bh;
                bh = affs_getzeroblk(sb, block);
                if (!bh)
                        goto err;
                break;
        default:
                break;
        }

        AFFS_HEAD(bh)->ptype = cpu_to_be32(T_SHORT);
        AFFS_HEAD(bh)->key = cpu_to_be32(bh->b_blocknr);
        affs_copy_name(AFFS_TAIL(sb, bh)->name, dentry);
        AFFS_TAIL(sb, bh)->stype = cpu_to_be32(type);
        AFFS_TAIL(sb, bh)->parent = cpu_to_be32(dir->i_ino);

        if (inode_bh) {
                __be32 chain;
                chain = AFFS_TAIL(sb, inode_bh)->link_chain;
                AFFS_TAIL(sb, bh)->original = cpu_to_be32(inode->i_ino);
                AFFS_TAIL(sb, bh)->link_chain = chain;
                AFFS_TAIL(sb, inode_bh)->link_chain = cpu_to_be32(block);
                affs_adjust_checksum(inode_bh, block - be32_to_cpu(chain));
                mark_buffer_dirty_inode(inode_bh, inode);
                inode->i_nlink = 2;
                atomic_inc(&inode->i_count);
        }
        affs_fix_checksum(sb, bh);
        mark_buffer_dirty_inode(bh, inode);
        dentry->d_fsdata = (void *)(long)bh->b_blocknr;

        affs_lock_dir(dir);
        retval = affs_insert_hash(dir, bh);
        mark_buffer_dirty_inode(bh, inode);
        affs_unlock_dir(dir);
        affs_unlock_link(inode);

        d_instantiate(dentry, inode);
done:
        affs_brelse(inode_bh);
        affs_brelse(bh);
        return retval;
err:
        if (block)
                affs_free_block(sb, block);
        affs_unlock_link(inode);
        goto done;
}

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