[funini.com] -> [kei@sodan] -> Kernel Reading

root/fs/hpfs/ea.c

/* [<][>][^][v][top][bottom][index][help] */

DEFINITIONS

This source file includes following definitions.
  1. hpfs_ea_ext_remove
  2. get_indirect_ea
  3. set_indirect_ea
  4. hpfs_read_ea
  5. hpfs_get_ea
  6. hpfs_set_ea

/*
 *  linux/fs/hpfs/ea.c
 *
 *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
 *
 *  handling extended attributes
 */

#include "hpfs_fn.h"

/* Remove external extended attributes. ano specifies whether a is a 
   direct sector where eas starts or an anode */

void hpfs_ea_ext_remove(struct super_block *s, secno a, int ano, unsigned len)
{
        unsigned pos = 0;
        while (pos < len) {
                char ex[4 + 255 + 1 + 8];
                struct extended_attribute *ea = (struct extended_attribute *)ex;
                if (pos + 4 > len) {
                        hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
                                ano ? "anode" : "sectors", a, len);
                        return;
                }
                if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return;
                if (ea->indirect) {
                        if (ea->valuelen != 8) {
                                hpfs_error(s, "ea->indirect set while ea->valuelen!=8, %s %08x, pos %08x",
                                        ano ? "anode" : "sectors", a, pos);
                                return;
                        }
                        if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 9, ex+4))
                                return;
                        hpfs_ea_remove(s, ea_sec(ea), ea->anode, ea_len(ea));
                }
                pos += ea->namelen + ea->valuelen + 5;
        }
        if (!ano) hpfs_free_sectors(s, a, (len+511) >> 9);
        else {
                struct buffer_head *bh;
                struct anode *anode;
                if ((anode = hpfs_map_anode(s, a, &bh))) {
                        hpfs_remove_btree(s, &anode->btree);
                        brelse(bh);
                        hpfs_free_sectors(s, a, 1);
                }
        }
}

static char *get_indirect_ea(struct super_block *s, int ano, secno a, int size)
{
        char *ret;
        if (!(ret = kmalloc(size + 1, GFP_NOFS))) {
                printk("HPFS: out of memory for EA\n");
                return NULL;
        }
        if (hpfs_ea_read(s, a, ano, 0, size, ret)) {
                kfree(ret);
                return NULL;
        }
        ret[size] = 0;
        return ret;
}

static void set_indirect_ea(struct super_block *s, int ano, secno a, char *data,
                            int size)
{
        hpfs_ea_write(s, a, ano, 0, size, data);
}

/* Read an extended attribute named 'key' into the provided buffer */

int hpfs_read_ea(struct super_block *s, struct fnode *fnode, char *key,
                char *buf, int size)
{
        unsigned pos;
        int ano, len;
        secno a;
        struct extended_attribute *ea;
        struct extended_attribute *ea_end = fnode_end_ea(fnode);
        for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
                if (!strcmp(ea->name, key)) {
                        if (ea->indirect)
                                goto indirect;
                        if (ea->valuelen >= size)
                                return -EINVAL;
                        memcpy(buf, ea_data(ea), ea->valuelen);
                        buf[ea->valuelen] = 0;
                        return 0;
                }
        a = fnode->ea_secno;
        len = fnode->ea_size_l;
        ano = fnode->ea_anode;
        pos = 0;
        while (pos < len) {
                char ex[4 + 255 + 1 + 8];
                ea = (struct extended_attribute *)ex;
                if (pos + 4 > len) {
                        hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
                                ano ? "anode" : "sectors", a, len);
                        return -EIO;
                }
                if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return -EIO;
                if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea->indirect ? 8 : 0), ex + 4))
                        return -EIO;
                if (!strcmp(ea->name, key)) {
                        if (ea->indirect)
                                goto indirect;
                        if (ea->valuelen >= size)
                                return -EINVAL;
                        if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea->valuelen, buf))
                                return -EIO;
                        buf[ea->valuelen] = 0;
                        return 0;
                }
                pos += ea->namelen + ea->valuelen + 5;
        }
        return -ENOENT;
indirect:
        if (ea_len(ea) >= size)
                return -EINVAL;
        if (hpfs_ea_read(s, ea_sec(ea), ea->anode, 0, ea_len(ea), buf))
                return -EIO;
        buf[ea_len(ea)] = 0;
        return 0;
}

/* Read an extended attribute named 'key' */
char *hpfs_get_ea(struct super_block *s, struct fnode *fnode, char *key, int *size)
{
        char *ret;
        unsigned pos;
        int ano, len;
        secno a;
        struct extended_attribute *ea;
        struct extended_attribute *ea_end = fnode_end_ea(fnode);
        for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
                if (!strcmp(ea->name, key)) {
                        if (ea->indirect)
                                return get_indirect_ea(s, ea->anode, ea_sec(ea), *size = ea_len(ea));
                        if (!(ret = kmalloc((*size = ea->valuelen) + 1, GFP_NOFS))) {
                                printk("HPFS: out of memory for EA\n");
                                return NULL;
                        }
                        memcpy(ret, ea_data(ea), ea->valuelen);
                        ret[ea->valuelen] = 0;
                        return ret;
                }
        a = fnode->ea_secno;
        len = fnode->ea_size_l;
        ano = fnode->ea_anode;
        pos = 0;
        while (pos < len) {
                char ex[4 + 255 + 1 + 8];
                ea = (struct extended_attribute *)ex;
                if (pos + 4 > len) {
                        hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
                                ano ? "anode" : "sectors", a, len);
                        return NULL;
                }
                if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return NULL;
                if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea->indirect ? 8 : 0), ex + 4))
                        return NULL;
                if (!strcmp(ea->name, key)) {
                        if (ea->indirect)
                                return get_indirect_ea(s, ea->anode, ea_sec(ea), *size = ea_len(ea));
                        if (!(ret = kmalloc((*size = ea->valuelen) + 1, GFP_NOFS))) {
                                printk("HPFS: out of memory for EA\n");
                                return NULL;
                        }
                        if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea->valuelen, ret)) {
                                kfree(ret);
                                return NULL;
                        }
                        ret[ea->valuelen] = 0;
                        return ret;
                }
                pos += ea->namelen + ea->valuelen + 5;
        }
        return NULL;
}

/* 
 * Update or create extended attribute 'key' with value 'data'. Note that
 * when this ea exists, it MUST have the same size as size of data.
 * This driver can't change sizes of eas ('cause I just don't need it).
 */

void hpfs_set_ea(struct inode *inode, struct fnode *fnode, char *key, char *data, int size)
{
        fnode_secno fno = inode->i_ino;
        struct super_block *s = inode->i_sb;
        unsigned pos;
        int ano, len;
        secno a;
        unsigned char h[4];
        struct extended_attribute *ea;
        struct extended_attribute *ea_end = fnode_end_ea(fnode);
        for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
                if (!strcmp(ea->name, key)) {
                        if (ea->indirect) {
                                if (ea_len(ea) == size)
                                        set_indirect_ea(s, ea->anode, ea_sec(ea), data, size);
                        } else if (ea->valuelen == size) {
                                memcpy(ea_data(ea), data, size);
                        }
                        return;
                }
        a = fnode->ea_secno;
        len = fnode->ea_size_l;
        ano = fnode->ea_anode;
        pos = 0;
        while (pos < len) {
                char ex[4 + 255 + 1 + 8];
                ea = (struct extended_attribute *)ex;
                if (pos + 4 > len) {
                        hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
                                ano ? "anode" : "sectors", a, len);
                        return;
                }
                if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return;
                if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea->indirect ? 8 : 0), ex + 4))
                        return;
                if (!strcmp(ea->name, key)) {
                        if (ea->indirect) {
                                if (ea_len(ea) == size)
                                        set_indirect_ea(s, ea->anode, ea_sec(ea), data, size);
                        }
                        else {
                                if (ea->valuelen == size)
                                        hpfs_ea_write(s, a, ano, pos + 4 + ea->namelen + 1, size, data);
                        }
                        return;
                }
                pos += ea->namelen + ea->valuelen + 5;
        }
        if (!fnode->ea_offs) {
                /*if (fnode->ea_size_s) {
                        hpfs_error(s, "fnode %08x: ea_size_s == %03x, ea_offs == 0",
                                inode->i_ino, fnode->ea_size_s);
                        return;
                }*/
                fnode->ea_offs = 0xc4;
        }
        if (fnode->ea_offs < 0xc4 || fnode->ea_offs + fnode->acl_size_s + fnode->ea_size_s > 0x200) {
                hpfs_error(s, "fnode %08lx: ea_offs == %03x, ea_size_s == %03x",
                        (unsigned long)inode->i_ino,
                        fnode->ea_offs, fnode->ea_size_s);
                return;
        }
        if ((fnode->ea_size_s || !fnode->ea_size_l) &&
             fnode->ea_offs + fnode->acl_size_s + fnode->ea_size_s + strlen(key) + size + 5 <= 0x200) {
                ea = fnode_end_ea(fnode);
                *(char *)ea = 0;
                ea->namelen = strlen(key);
                ea->valuelen = size;
                strcpy(ea->name, key);
                memcpy(ea_data(ea), data, size);
                fnode->ea_size_s += strlen(key) + size + 5;
                goto ret;
        }
        /* Most the code here is 99.9993422% unused. I hope there are no bugs.
           But what .. HPFS.IFS has also bugs in ea management. */
        if (fnode->ea_size_s && !fnode->ea_size_l) {
                secno n;
                struct buffer_head *bh;
                char *data;
                if (!(n = hpfs_alloc_sector(s, fno, 1, 0, 1))) return;
                if (!(data = hpfs_get_sector(s, n, &bh))) {
                        hpfs_free_sectors(s, n, 1);
                        return;
                }
                memcpy(data, fnode_ea(fnode), fnode->ea_size_s);
                fnode->ea_size_l = fnode->ea_size_s;
                fnode->ea_size_s = 0;
                fnode->ea_secno = n;
                fnode->ea_anode = 0;
                mark_buffer_dirty(bh);
                brelse(bh);
        }
        pos = fnode->ea_size_l + 5 + strlen(key) + size;
        len = (fnode->ea_size_l + 511) >> 9;
        if (pos >= 30000) goto bail;
        while (((pos + 511) >> 9) > len) {
                if (!len) {
                        if (!(fnode->ea_secno = hpfs_alloc_sector(s, fno, 1, 0, 1)))
                                goto bail;
                        fnode->ea_anode = 0;
                        len++;
                } else if (!fnode->ea_anode) {
                        if (hpfs_alloc_if_possible(s, fnode->ea_secno + len)) {
                                len++;
                        } else {
                                /* Aargh... don't know how to create ea anodes :-( */
                                /*struct buffer_head *bh;
                                struct anode *anode;
                                anode_secno a_s;
                                if (!(anode = hpfs_alloc_anode(s, fno, &a_s, &bh)))
                                        goto bail;
                                anode->up = fno;
                                anode->btree.fnode_parent = 1;
                                anode->btree.n_free_nodes--;
                                anode->btree.n_used_nodes++;
                                anode->btree.first_free += 12;
                                anode->u.external[0].disk_secno = fnode->ea_secno;
                                anode->u.external[0].file_secno = 0;
                                anode->u.external[0].length = len;
                                mark_buffer_dirty(bh);
                                brelse(bh);
                                fnode->ea_anode = 1;
                                fnode->ea_secno = a_s;*/
                                secno new_sec;
                                int i;
                                if (!(new_sec = hpfs_alloc_sector(s, fno, 1, 1 - ((pos + 511) >> 9), 1)))
                                        goto bail;
                                for (i = 0; i < len; i++) {
                                        struct buffer_head *bh1, *bh2;
                                        void *b1, *b2;
                                        if (!(b1 = hpfs_map_sector(s, fnode->ea_secno + i, &bh1, len - i - 1))) {
                                                hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
                                                goto bail;
                                        }
                                        if (!(b2 = hpfs_get_sector(s, new_sec + i, &bh2))) {
                                                brelse(bh1);
                                                hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
                                                goto bail;
                                        }
                                        memcpy(b2, b1, 512);
                                        brelse(bh1);
                                        mark_buffer_dirty(bh2);
                                        brelse(bh2);
                                }
                                hpfs_free_sectors(s, fnode->ea_secno, len);
                                fnode->ea_secno = new_sec;
                                len = (pos + 511) >> 9;
                        }
                }
                if (fnode->ea_anode) {
                        if (hpfs_add_sector_to_btree(s, fnode->ea_secno,
                                                     0, len) != -1) {
                                len++;
                        } else {
                                goto bail;
                        }
                }
        }
        h[0] = 0;
        h[1] = strlen(key);
        h[2] = size & 0xff;
        h[3] = size >> 8;
        if (hpfs_ea_write(s, fnode->ea_secno, fnode->ea_anode, fnode->ea_size_l, 4, h)) goto bail;
        if (hpfs_ea_write(s, fnode->ea_secno, fnode->ea_anode, fnode->ea_size_l + 4, h[1] + 1, key)) goto bail;
        if (hpfs_ea_write(s, fnode->ea_secno, fnode->ea_anode, fnode->ea_size_l + 5 + h[1], size, data)) goto bail;
        fnode->ea_size_l = pos;
        ret:
        hpfs_i(inode)->i_ea_size += 5 + strlen(key) + size;
        return;
        bail:
        if (fnode->ea_secno)
                if (fnode->ea_anode) hpfs_truncate_btree(s, fnode->ea_secno, 1, (fnode->ea_size_l + 511) >> 9);
                else hpfs_free_sectors(s, fnode->ea_secno + ((fnode->ea_size_l + 511) >> 9), len - ((fnode->ea_size_l + 511) >> 9));
        else fnode->ea_secno = fnode->ea_size_l = 0;
}
        

/* [<][>][^][v][top][bottom][index][help] */

[funini.com] -> [kei@sodan] -> Kernel Reading