/*
* fileio.c --- Simple file I/O routines
- *
+ *
* Copyright (C) 1997 Theodore Ts'o.
*
* %Begin-Header%
- * This file may be redistributed under the terms of the GNU Public
- * License.
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
* %End-Header%
*/
+#include "config.h"
#include <stdio.h>
#include <string.h>
#if HAVE_UNISTD_H
#include "ext2_fs.h"
#include "ext2fs.h"
+#include "ext2fsP.h"
struct ext2_file {
errcode_t magic;
struct ext2_inode inode;
int flags;
__u64 pos;
- blk_t blockno;
- blk_t physblock;
+ blk64_t blockno;
+ blk64_t physblock;
char *buf;
};
+struct block_entry {
+ blk64_t physblock;
+ unsigned char sha[EXT2FS_SHA512_LENGTH];
+};
+typedef struct block_entry *block_entry_t;
+
#define BMAP_BUFFER (file->buf + fs->blocksize)
errcode_t ext2fs_file_open2(ext2_filsys fs, ext2_ino_t ino,
retval = ext2fs_get_mem(sizeof(struct ext2_file), &file);
if (retval)
return retval;
-
+
memset(file, 0, sizeof(struct ext2_file));
file->magic = EXT2_ET_MAGIC_EXT2_FILE;
file->fs = fs;
if (retval)
goto fail;
}
-
+
retval = ext2fs_get_array(3, fs->blocksize, &file->buf);
if (retval)
goto fail;
*ret = file;
return 0;
-
+
fail:
if (file->buf)
ext2fs_free_mem(&file->buf);
}
/*
+ * This function returns the pointer to the inode of a file from the structure
+ */
+struct ext2_inode *ext2fs_file_get_inode(ext2_file_t file)
+{
+ if (file->magic != EXT2_ET_MAGIC_EXT2_FILE)
+ return NULL;
+ return &file->inode;
+}
+
+/* This function returns the inode number from the structure */
+ext2_ino_t ext2fs_file_get_inode_num(ext2_file_t file)
+{
+ if (file->magic != EXT2_ET_MAGIC_EXT2_FILE)
+ return 0;
+ return file->ino;
+}
+
+/*
* This function flushes the dirty block buffer out to disk if
* necessary.
*/
{
errcode_t retval;
ext2_filsys fs;
-
+ int ret_flags;
+ blk64_t dontcare;
+
EXT2_CHECK_MAGIC(file, EXT2_ET_MAGIC_EXT2_FILE);
fs = file->fs;
!(file->flags & EXT2_FILE_BUF_DIRTY))
return 0;
+ /* Is this an uninit block? */
+ if (file->physblock && file->inode.i_flags & EXT4_EXTENTS_FL) {
+ retval = ext2fs_bmap2(fs, file->ino, &file->inode, BMAP_BUFFER,
+ 0, file->blockno, &ret_flags, &dontcare);
+ if (retval)
+ return retval;
+ if (ret_flags & BMAP_RET_UNINIT) {
+ retval = ext2fs_bmap2(fs, file->ino, &file->inode,
+ BMAP_BUFFER, BMAP_SET,
+ file->blockno, 0,
+ &file->physblock);
+ if (retval)
+ return retval;
+ }
+ }
+
/*
* OK, the physical block hasn't been allocated yet.
* Allocate it.
*/
if (!file->physblock) {
- retval = ext2fs_bmap(fs, file->ino, &file->inode,
+ retval = ext2fs_bmap2(fs, file->ino, &file->inode,
BMAP_BUFFER, file->ino ? BMAP_ALLOC : 0,
- file->blockno, &file->physblock);
+ file->blockno, 0, &file->physblock);
if (retval)
return retval;
}
- retval = io_channel_write_blk(fs->io, file->physblock,
- 1, file->buf);
+ retval = io_channel_write_blk64(fs->io, file->physblock, 1, file->buf);
if (retval)
return retval;
*/
static errcode_t sync_buffer_position(ext2_file_t file)
{
- blk_t b;
+ blk64_t b;
errcode_t retval;
b = file->pos / file->fs->blocksize;
{
ext2_filsys fs = file->fs;
errcode_t retval;
+ int ret_flags;
if (!(file->flags & EXT2_FILE_BUF_VALID)) {
- retval = ext2fs_bmap(fs, file->ino, &file->inode,
- BMAP_BUFFER, 0, file->blockno,
+ retval = ext2fs_bmap2(fs, file->ino, &file->inode,
+ BMAP_BUFFER, 0, file->blockno, &ret_flags,
&file->physblock);
if (retval)
return retval;
if (!dontfill) {
- if (file->physblock) {
- retval = io_channel_read_blk(fs->io,
- file->physblock,
- 1, file->buf);
+ if (file->physblock &&
+ !(ret_flags & BMAP_RET_UNINIT)) {
+ retval = io_channel_read_blk64(fs->io,
+ file->physblock,
+ 1, file->buf);
if (retval)
return retval;
} else
}
return 0;
}
-
+
errcode_t ext2fs_file_close(ext2_file_t file)
{
errcode_t retval;
-
+
EXT2_CHECK_MAGIC(file, EXT2_ET_MAGIC_EXT2_FILE);
retval = ext2fs_file_flush(file);
-
+
if (file->buf)
ext2fs_free_mem(&file->buf);
ext2fs_free_mem(&file);
}
+static errcode_t
+ext2fs_file_read_inline_data(ext2_file_t file, void *buf,
+ unsigned int wanted, unsigned int *got)
+{
+ ext2_filsys fs;
+ errcode_t retval;
+ unsigned int count = 0;
+ size_t size;
+
+ fs = file->fs;
+ retval = ext2fs_inline_data_get(fs, file->ino, &file->inode,
+ file->buf, &size);
+ if (retval)
+ return retval;
+
+ if (file->pos >= size)
+ goto out;
+
+ count = size - file->pos;
+ if (count > wanted)
+ count = wanted;
+ memcpy(buf, file->buf + file->pos, count);
+ file->pos += count;
+ buf = (char *) buf + count;
+
+out:
+ if (got)
+ *got = count;
+ return retval;
+}
+
+
errcode_t ext2fs_file_read(ext2_file_t file, void *buf,
unsigned int wanted, unsigned int *got)
{
EXT2_CHECK_MAGIC(file, EXT2_ET_MAGIC_EXT2_FILE);
fs = file->fs;
+ /* If an inode has inline data, things get complicated. */
+ if (file->inode.i_flags & EXT4_INLINE_DATA_FL)
+ return ext2fs_file_read_inline_data(file, buf, wanted, got);
+
while ((file->pos < EXT2_I_SIZE(&file->inode)) && (wanted > 0)) {
retval = sync_buffer_position(file);
if (retval)
left = EXT2_I_SIZE(&file->inode) - file->pos ;
if (c > left)
c = left;
-
+
memcpy(ptr, file->buf+start, c);
file->pos += c;
ptr += c;
count += c;
wanted -= c;
}
-
+
fail:
if (got)
*got = count;
}
+static errcode_t
+ext2fs_file_write_inline_data(ext2_file_t file, const void *buf,
+ unsigned int nbytes, unsigned int *written)
+{
+ ext2_filsys fs;
+ errcode_t retval;
+ unsigned int count = 0;
+ size_t size;
+
+ fs = file->fs;
+ retval = ext2fs_inline_data_get(fs, file->ino, &file->inode,
+ file->buf, &size);
+ if (retval)
+ return retval;
+
+ if (file->pos < size) {
+ count = nbytes - file->pos;
+ memcpy(file->buf + file->pos, buf, count);
+
+ retval = ext2fs_inline_data_set(fs, file->ino, &file->inode,
+ file->buf, count);
+ if (retval == EXT2_ET_INLINE_DATA_NO_SPACE)
+ goto expand;
+ if (retval)
+ return retval;
+
+ file->pos += count;
+
+ /* Update inode size */
+ if (count != 0 && EXT2_I_SIZE(&file->inode) < file->pos) {
+ errcode_t rc;
+
+ rc = ext2fs_file_set_size2(file, file->pos);
+ if (retval == 0)
+ retval = rc;
+ }
+
+ if (written)
+ *written = count;
+ return 0;
+ }
+
+expand:
+ retval = ext2fs_inline_data_expand(fs, file->ino);
+ if (retval)
+ return retval;
+ /*
+ * reload inode and return no space error
+ *
+ * XXX: file->inode could be copied from the outside
+ * in ext2fs_file_open2(). We have no way to modify
+ * the outside inode.
+ */
+ retval = ext2fs_read_inode(fs, file->ino, &file->inode);
+ if (retval)
+ return retval;
+ return EXT2_ET_INLINE_DATA_NO_SPACE;
+}
+
+
errcode_t ext2fs_file_write(ext2_file_t file, const void *buf,
unsigned int nbytes, unsigned int *written)
{
errcode_t retval = 0;
unsigned int start, c, count = 0;
const char *ptr = (const char *) buf;
+ block_entry_t new_block = NULL, old_block = NULL;
+ int bmap_flags = 0;
EXT2_CHECK_MAGIC(file, EXT2_ET_MAGIC_EXT2_FILE);
fs = file->fs;
if (!(file->flags & EXT2_FILE_WRITE))
return EXT2_ET_FILE_RO;
+ /* If an inode has inline data, things get complicated. */
+ if (file->inode.i_flags & EXT4_INLINE_DATA_FL) {
+ retval = ext2fs_file_write_inline_data(file, buf, nbytes,
+ written);
+ if (retval != EXT2_ET_INLINE_DATA_NO_SPACE)
+ return retval;
+ /* fall through to read data from the block */
+ retval = 0;
+ }
+
while (nbytes > 0) {
retval = sync_buffer_position(file);
if (retval)
goto fail;
-
+
start = file->pos % fs->blocksize;
c = fs->blocksize - start;
if (c > nbytes)
file->flags |= EXT2_FILE_BUF_DIRTY;
memcpy(file->buf+start, ptr, c);
+
+ /*
+ * OK, the physical block hasn't been allocated yet.
+ * Allocate it.
+ */
+ if (!file->physblock) {
+ bmap_flags = (file->ino ? BMAP_ALLOC : 0);
+ if (fs->flags & EXT2_FLAG_SHARE_DUP) {
+ new_block = calloc(1, sizeof(*new_block));
+ if (!new_block) {
+ retval = EXT2_ET_NO_MEMORY;
+ goto fail;
+ }
+ ext2fs_sha512((const unsigned char*)file->buf,
+ fs->blocksize, new_block->sha);
+ old_block = ext2fs_hashmap_lookup(
+ fs->block_sha_map,
+ new_block->sha,
+ sizeof(new_block->sha));
+ }
+
+ if (old_block) {
+ file->physblock = old_block->physblock;
+ bmap_flags |= BMAP_SET;
+ free(new_block);
+ new_block = NULL;
+ }
+
+ retval = ext2fs_bmap2(fs, file->ino, &file->inode,
+ BMAP_BUFFER,
+ bmap_flags,
+ file->blockno, 0,
+ &file->physblock);
+ if (retval) {
+ free(new_block);
+ new_block = NULL;
+ goto fail;
+ }
+
+ if (new_block) {
+ new_block->physblock = file->physblock;
+ ext2fs_hashmap_add(fs->block_sha_map, new_block,
+ new_block->sha, sizeof(new_block->sha));
+ }
+
+ if (bmap_flags & BMAP_SET) {
+ ext2fs_iblk_add_blocks(fs, &file->inode, 1);
+ ext2fs_write_inode(fs, file->ino, &file->inode);
+ }
+ }
+
file->pos += c;
ptr += c;
count += c;
nbytes -= c;
}
-
+
fail:
+ /* Update inode size */
+ if (count != 0 && EXT2_I_SIZE(&file->inode) < file->pos) {
+ errcode_t rc;
+
+ rc = ext2fs_file_set_size2(file, file->pos);
+ if (retval == 0)
+ retval = rc;
+ }
+
if (written)
*written = count;
return retval;
errcode_t ext2fs_file_lseek(ext2_file_t file, ext2_off_t offset,
int whence, ext2_off_t *ret_pos)
{
- __u64 loffset, ret_loffset;
+ __u64 loffset, ret_loffset = 0;
errcode_t retval;
-
+
loffset = offset;
retval = ext2fs_file_llseek(file, loffset, whence, &ret_loffset);
if (ret_pos)
return size;
}
+/* Zero the parts of the last block that are past EOF. */
+static errcode_t ext2fs_file_zero_past_offset(ext2_file_t file,
+ ext2_off64_t offset)
+{
+ ext2_filsys fs = file->fs;
+ char *b = NULL;
+ ext2_off64_t off = offset % fs->blocksize;
+ blk64_t blk;
+ int ret_flags;
+ errcode_t retval;
+
+ if (off == 0)
+ return 0;
+
+ retval = sync_buffer_position(file);
+ if (retval)
+ return retval;
+
+ /* Is there an initialized block at the end? */
+ retval = ext2fs_bmap2(fs, file->ino, NULL, NULL, 0,
+ offset / fs->blocksize, &ret_flags, &blk);
+ if (retval)
+ return retval;
+ if ((blk == 0) || (ret_flags & BMAP_RET_UNINIT))
+ return 0;
+
+ /* Zero to the end of the block */
+ retval = ext2fs_get_mem(fs->blocksize, &b);
+ if (retval)
+ return retval;
+
+ /* Read/zero/write block */
+ retval = io_channel_read_blk64(fs->io, blk, 1, b);
+ if (retval)
+ goto out;
+
+ memset(b + off, 0, fs->blocksize - off);
+
+ retval = io_channel_write_blk64(fs->io, blk, 1, b);
+ if (retval)
+ goto out;
+
+out:
+ ext2fs_free_mem(&b);
+ return retval;
+}
+
/*
* This function sets the size of the file, truncating it if necessary
- *
- * XXX still need to call truncate
+ *
*/
-errcode_t ext2fs_file_set_size(ext2_file_t file, ext2_off_t size)
+errcode_t ext2fs_file_set_size2(ext2_file_t file, ext2_off64_t size)
{
+ ext2_off64_t old_size;
errcode_t retval;
+ blk64_t old_truncate, truncate_block;
+
EXT2_CHECK_MAGIC(file, EXT2_ET_MAGIC_EXT2_FILE);
-
- file->inode.i_size = size;
- file->inode.i_size_high = 0;
+
+ if (size && ext2fs_file_block_offset_too_big(file->fs, &file->inode,
+ (size - 1) / file->fs->blocksize))
+ return EXT2_ET_FILE_TOO_BIG;
+ truncate_block = ((size + file->fs->blocksize - 1) >>
+ EXT2_BLOCK_SIZE_BITS(file->fs->super));
+ old_size = EXT2_I_SIZE(&file->inode);
+ old_truncate = ((old_size + file->fs->blocksize - 1) >>
+ EXT2_BLOCK_SIZE_BITS(file->fs->super));
+
+ retval = ext2fs_inode_size_set(file->fs, &file->inode, size);
+ if (retval)
+ return retval;
+
if (file->ino) {
retval = ext2fs_write_inode(file->fs, file->ino, &file->inode);
if (retval)
return retval;
}
- /*
- * XXX truncate inode if necessary
- */
+ retval = ext2fs_file_zero_past_offset(file, size);
+ if (retval)
+ return retval;
- return 0;
+ if (truncate_block >= old_truncate)
+ return 0;
+
+ return ext2fs_punch(file->fs, file->ino, &file->inode, 0,
+ truncate_block, ~0ULL);
+}
+
+errcode_t ext2fs_file_set_size(ext2_file_t file, ext2_off_t size)
+{
+ return ext2fs_file_set_size2(file, size);
}
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