source: mainline/uspace/srv/fs/minixfs/mfs_inode.c@ 13ecdac9

/*
 * Copyright (c) 2011 Maurizio Lombardi
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup fs
 * @{
 */

#include <stdlib.h>
#include "mfs.h"
#include "mfs_utils.h"

static int
mfs_write_inode_raw(struct mfs_node *mnode);

static int
mfs2_write_inode_raw(struct mfs_node *mnode);

static struct mfs_ino_info *
mfs_read_inode_raw(const struct mfs_instance *instance, uint16_t inum);

static struct mfs_ino_info *
mfs2_read_inode_raw(const struct mfs_instance *instance, uint32_t inum);


int
get_inode(struct mfs_instance *inst, struct mfs_ino_info **ino_i,
          fs_index_t index)
{
        struct mfs_sb_info *sbi = inst->sbi;

        if (sbi->fs_version == MFS_VERSION_V1) {
                /*Read a MFS V1 inode*/
                *ino_i = mfs_read_inode_raw(inst, index);
        } else {
                /*Read a MFS V2/V3 inode*/
                *ino_i = mfs2_read_inode_raw(inst, index);
        }

        if (*ino_i == NULL)
                return -1;

        return EOK;
}

static struct mfs_ino_info *
mfs_read_inode_raw(const struct mfs_instance *instance, uint16_t inum) {
        struct mfs_inode *ino = NULL;
        struct mfs_ino_info *ino_i = NULL;
        struct mfs_sb_info *sbi;
        block_t *b;
        int i;

        sbi = instance->sbi;
        assert(sbi);

        /*inode 0 does not exist*/
        inum -= 1;

        const int ino_off = inum % sbi->ino_per_block;
        const size_t ino_size = sizeof(struct mfs_inode);

        ino_i = malloc(sizeof(*ino_i));
        ino = malloc(ino_size);

        if (!ino || !ino_i)
                goto out_err;

        const int itable_off = sbi->itable_off;

        if (block_get(&b, instance->handle,
                      itable_off + inum / sbi->ino_per_block,
                      BLOCK_FLAGS_NONE) != EOK)
                goto out_err;

        memcpy(ino, ((uint8_t *) b->data) + ino_off * ino_size, ino_size);

        ino_i->i_mode = conv16(sbi->native, ino->i_mode);
        ino_i->i_uid = conv16(sbi->native, ino->i_uid);
        ino_i->i_size = conv32(sbi->native, ino->i_size);
        ino_i->i_mtime = conv32(sbi->native, ino->i_mtime);
        ino_i->i_nlinks = ino->i_nlinks;

        for (i = 0; i < V1_NR_DIRECT_ZONES; ++i)
                ino_i->i_dzone[i] = conv16(sbi->native, ino->i_dzone[i]);

        for (i = 0; i < V1_NR_INDIRECT_ZONES; ++i)
                ino_i->i_izone[i] = conv16(sbi->native, ino->i_izone[i]);

        block_put(b);
        free(ino);
        ino_i->dirty = false;

        return ino_i;

out_err:
        if (ino)
                free(ino);
        if (ino_i)
                free(ino_i);
        return NULL;
}

static struct mfs_ino_info *
mfs2_read_inode_raw(const struct mfs_instance *instance, uint32_t inum) {
        struct mfs2_inode *ino = NULL;
        struct mfs_ino_info *ino_i = NULL;
        struct mfs_sb_info *sbi;
        block_t *b;
        int i;

        const size_t ino_size = sizeof(struct mfs2_inode);

        ino = malloc(ino_size);
        ino_i = malloc(sizeof(*ino_i));

        if (!ino || !ino_i)
                goto out_err;

        sbi = instance->sbi;
        assert(sbi);

        /*inode 0 does not exist*/
        inum -= 1;

        const int itable_off = sbi->itable_off;
        const int ino_off = inum % sbi->ino_per_block;

        if (block_get(&b, instance->handle,
                      itable_off + inum / sbi->ino_per_block,
                      BLOCK_FLAGS_NONE) != EOK)
                goto out_err;

        memcpy(ino, b->data + ino_off * ino_size, ino_size);

        ino_i->i_mode = conv16(sbi->native, ino->i_mode);
        ino_i->i_nlinks = conv16(sbi->native, ino->i_nlinks);
        ino_i->i_uid = conv16(sbi->native, ino->i_uid);
        ino_i->i_gid = conv16(sbi->native, ino->i_gid);
        ino_i->i_size = conv32(sbi->native, ino->i_size);
        ino_i->i_atime = conv32(sbi->native, ino->i_atime);
        ino_i->i_mtime = conv32(sbi->native, ino->i_mtime);
        ino_i->i_ctime = conv32(sbi->native, ino->i_ctime);

        for (i = 0; i < V2_NR_DIRECT_ZONES; ++i)
                ino_i->i_dzone[i] = conv32(sbi->native, ino->i_dzone[i]);

        for (i = 0; i < V2_NR_INDIRECT_ZONES; ++i)
                ino_i->i_izone[i] = conv32(sbi->native, ino->i_izone[i]);

        block_put(b);
        free(ino);
        ino_i->dirty = false;

        return ino_i;

out_err:
        if (ino)
                free(ino);
        if (ino_i)
                free(ino_i);
        return NULL;
}

int
put_inode(struct mfs_node *mnode)
{
        int rc = EOK;

        assert(mnode);
        assert(mnode->ino_i);

        if (!mnode->ino_i->dirty)
                goto out;

        struct mfs_instance *inst = mnode->instance;
        assert(inst);
        struct mfs_sb_info *sbi = inst->sbi;
        assert(sbi);

        if (sbi->fs_version == MFS_VERSION_V1)
                rc = mfs_write_inode_raw(mnode);
        else
                rc = mfs2_write_inode_raw(mnode);

out:
        return rc;
}

static int
mfs_write_inode_raw(struct mfs_node *mnode)
{
        int i, r;
        block_t *b;
        struct mfs_ino_info *ino_i = mnode->ino_i;
        struct mfs_sb_info *sbi = mnode->instance->sbi;

        const uint32_t inum = ino_i->index - 1;
        const int itable_off = sbi->itable_off;
        const int ino_off = inum % sbi->ino_per_block;
        const bool native = sbi->native;

        r = block_get(&b, mnode->instance->handle,
                      itable_off + inum / sbi->ino_per_block,
                      BLOCK_FLAGS_NONE);

        on_error(r, goto out);

        struct mfs_inode *ino = b->data;
        ino += ino_off;

        ino->i_mode = conv16(native, ino_i->i_mode);
        ino->i_uid = conv16(native, ino_i->i_uid);
        ino->i_gid = ino_i->i_gid;
        ino->i_nlinks = ino_i->i_nlinks;
        ino->i_size = conv32(native, ino_i->i_size);
        ino->i_mtime = conv32(native, ino_i->i_mtime);

        for (i = 0; i < V1_NR_DIRECT_ZONES; ++i)
                ino->i_dzone[i] = conv16(native, ino_i->i_dzone[i]);
        for (i = 0; i < V1_NR_INDIRECT_ZONES; ++i)
                ino->i_izone[i] = conv16(native, ino_i->i_izone[i]);

        b->dirty = true;
        block_put(b);

        ino_i->dirty = false;
out:
        return r;
}

static int
mfs2_write_inode_raw(struct mfs_node *mnode)
{
        struct mfs_ino_info *ino_i = mnode->ino_i;
        struct mfs_sb_info *sbi = mnode->instance->sbi;
        block_t *b;
        int i, r;

        const uint32_t inum = ino_i->index - 1;
        const int itable_off = sbi->itable_off;
        const int ino_off = inum % sbi->ino_per_block;
        const bool native = sbi->native;

        r = block_get(&b, mnode->instance->handle,
                      itable_off + inum / sbi->ino_per_block,
                      BLOCK_FLAGS_NONE);

        on_error(r, goto out);

        struct mfs2_inode *ino2 = b->data;
        ino2 += ino_off;

        ino2->i_mode = conv16(native, ino_i->i_mode);
        ino2->i_nlinks = conv16(native, ino_i->i_nlinks);
        ino2->i_uid = conv16(native, ino_i->i_uid);
        ino2->i_gid = conv16(native, ino_i->i_gid);
        ino2->i_size = conv32(native, ino_i->i_size);
        ino2->i_atime = conv32(native, ino_i->i_atime);
        ino2->i_mtime = conv32(native, ino_i->i_mtime);
        ino2->i_ctime = conv32(native, ino_i->i_ctime);

        for (i = 0; i < V2_NR_DIRECT_ZONES; ++i)
                ino2->i_dzone[i] = conv32(native, ino_i->i_dzone[i]);

        for (i = 0; i < V2_NR_INDIRECT_ZONES; ++i)
                ino2->i_izone[i] = conv32(native, ino_i->i_izone[i]);

        b->dirty = true;
        block_put(b);
        ino_i->dirty = false;

out:
        return r;
}

int
inode_shrink(struct mfs_node *mnode, size_t size_shrink)
{
        struct mfs_sb_info *sbi = mnode->instance->sbi;
        struct mfs_ino_info *ino_i = mnode->ino_i;
        const size_t bs = sbi->block_size;
        int r;

        assert(size_shrink > 0);

        const size_t old_size = ino_i->i_size;
        const size_t new_size = ino_i->i_size - size_shrink;

        assert(size_shrink <= old_size);

        ino_i->dirty = true;

        /*Compute the number of zones to free*/
        unsigned zones_to_free = 0;
        if (new_size == 0)
                ++zones_to_free;

        zones_to_free += (old_size / bs) - (new_size / bs);

        mfsdebug("zones to free = %u\n", zones_to_free);

        uint32_t pos = old_size - 1;
        unsigned i;
        for (i = 0; i < zones_to_free; ++i, pos -= bs) {
                uint32_t old_zone;

                r = write_map(mnode, pos, 0, &old_zone);
                on_error(r, goto exit_error);

                ino_i->i_size -= bs;

                if (old_zone == 0)
                        continue; /*Sparse block*/

                r = mfs_free_bit(mnode->instance, old_zone, BMAP_ZONE);
                on_error(r, goto exit_error);
        }

        ino_i->i_size = new_size;
        return EOK;

exit_error:
        return r;
}

int
inode_grow(struct mfs_node *mnode, size_t size_grow)
{
        unsigned i;
        struct mfs_sb_info *sbi = mnode->instance->sbi;
        struct mfs_ino_info *ino_i = mnode->ino_i;
        const int bs = sbi->block_size;

        const uint32_t old_size = ino_i->i_size;
        const uint32_t new_size = old_size + size_grow;

        assert(size_grow > 0);

        /*Compute the number of zones to add to the inode*/
        unsigned zones_to_add = 0;
        if (old_size == 0)
                ++zones_to_add;

        zones_to_add += (new_size / bs) - (old_size / bs);

        /*Compute the start zone*/
        unsigned start_zone = old_size / bs;
        start_zone += (old_size % bs) != 0;

        mfsdebug("zones to add = %u\n", zones_to_add);

        int r;
        for (i = 0; i < zones_to_add; ++i) {
                uint32_t new_zone;
                uint32_t dummy;

                r = mfs_alloc_bit(mnode->instance, &new_zone, BMAP_ZONE);
                on_error(r, return r);

                mfsdebug("write_map = %d\n", (int) ((start_zone + i) * bs));

                block_t *b;
                r = block_get(&b, mnode->instance->handle, new_zone,
                              BLOCK_FLAGS_NOREAD);
                on_error(r, return r);

                memset(b->data, 0, bs);
                b->dirty = true;
                block_put(b);

                r = write_map(mnode, (start_zone + i) * bs,
                              new_zone, &dummy);

                on_error(r, return r);

                ino_i->i_size += bs;
                ino_i->dirty = true;
        }

        ino_i->i_size = new_size;
        ino_i->dirty = true;

        return EOK;
}

/**
 * @}
 */