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-rw-r--r--fs/ext4/ext4_common.c76
-rw-r--r--fs/ext4/ext4_common.h2
-rw-r--r--fs/ext4/ext4_journal.c22
-rw-r--r--fs/ext4/ext4_write.c66
-rw-r--r--fs/ext4/ext4fs.c51
5 files changed, 159 insertions, 58 deletions
diff --git a/fs/ext4/ext4_common.c b/fs/ext4/ext4_common.c
index 67e2471bd3..464c33d0d7 100644
--- a/fs/ext4/ext4_common.c
+++ b/fs/ext4/ext4_common.c
@@ -190,7 +190,7 @@ uint32_t ext4fs_div_roundup(uint32_t size, uint32_t n)
return res;
}
-void put_ext4(uint64_t off, void *buf, uint32_t size)
+void put_ext4(uint64_t off, const void *buf, uint32_t size)
{
uint64_t startblock;
uint64_t remainder;
@@ -510,7 +510,8 @@ restart:
restart_read:
/* read the block no allocated to a file */
- first_block_no_of_root = read_allocated_block(g_parent_inode, blk_idx);
+ first_block_no_of_root = read_allocated_block(g_parent_inode, blk_idx,
+ NULL);
if (first_block_no_of_root <= 0)
goto fail;
@@ -607,7 +608,7 @@ restart_read:
dir->direntlen = cpu_to_le16(fs->blksz - totalbytes);
dir->namelen = strlen(filename);
- dir->filetype = FILETYPE_REG; /* regular file */
+ dir->filetype = file_type;
temp_dir = (char *)dir;
temp_dir = temp_dir + sizeof(struct ext2_dirent);
memcpy(temp_dir, filename, strlen(filename));
@@ -646,7 +647,7 @@ static int search_dir(struct ext2_inode *parent_inode, char *dirname)
/* get the block no allocated to a file */
for (blk_idx = 0; blk_idx < directory_blocks; blk_idx++) {
- blknr = read_allocated_block(parent_inode, blk_idx);
+ blknr = read_allocated_block(parent_inode, blk_idx, NULL);
if (blknr <= 0)
goto fail;
@@ -943,7 +944,7 @@ int ext4fs_filename_unlink(char *filename)
/* read the block no allocated to a file */
for (blk_idx = 0; blk_idx < directory_blocks; blk_idx++) {
- blknr = read_allocated_block(g_parent_inode, blk_idx);
+ blknr = read_allocated_block(g_parent_inode, blk_idx, NULL);
if (blknr <= 0)
break;
inodeno = unlink_filename(filename, blknr);
@@ -1522,7 +1523,7 @@ void ext4fs_allocate_blocks(struct ext2_inode *file_inode,
#endif
static struct ext4_extent_header *ext4fs_get_extent_block
- (struct ext2_data *data, char *buf,
+ (struct ext2_data *data, struct ext_block_cache *cache,
struct ext4_extent_header *ext_block,
uint32_t fileblock, int log2_blksz)
{
@@ -1546,17 +1547,19 @@ static struct ext4_extent_header *ext4fs_get_extent_block
break;
} while (fileblock >= le32_to_cpu(index[i].ei_block));
- if (--i < 0)
- return NULL;
+ /*
+ * If first logical block number is higher than requested fileblock,
+ * it is a sparse file. This is handled on upper layer.
+ */
+ if (i > 0)
+ i--;
block = le16_to_cpu(index[i].ei_leaf_hi);
block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo);
-
- if (ext4fs_devread((lbaint_t)block << log2_blksz, 0, blksz,
- buf))
- ext_block = (struct ext4_extent_header *)buf;
- else
+ block <<= log2_blksz;
+ if (!ext_cache_read(cache, (lbaint_t)block, blksz))
return NULL;
+ ext_block = (struct ext4_extent_header *)cache->buf;
}
}
@@ -1584,7 +1587,7 @@ static int ext4fs_blockgroup
int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode)
{
- struct ext2_block_group blkgrp;
+ struct ext2_block_group *blkgrp;
struct ext2_sblock *sblock = &data->sblock;
struct ext_filesystem *fs = get_fs();
int log2blksz = get_fs()->dev_desc->log2blksz;
@@ -1592,17 +1595,28 @@ int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode)
long int blkno;
unsigned int blkoff;
+ /* Allocate blkgrp based on gdsize (for 64-bit support). */
+ blkgrp = zalloc(get_fs()->gdsize);
+ if (!blkgrp)
+ return 0;
+
/* It is easier to calculate if the first inode is 0. */
ino--;
status = ext4fs_blockgroup(data, ino / le32_to_cpu
- (sblock->inodes_per_group), &blkgrp);
- if (status == 0)
+ (sblock->inodes_per_group), blkgrp);
+ if (status == 0) {
+ free(blkgrp);
return 0;
+ }
inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz;
- blkno = ext4fs_bg_get_inode_table_id(&blkgrp, fs) +
+ blkno = ext4fs_bg_get_inode_table_id(blkgrp, fs) +
(ino % le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block;
blkoff = (ino % inodes_per_block) * fs->inodesz;
+
+ /* Free blkgrp as it is no longer required. */
+ free(blkgrp);
+
/* Read the inode. */
status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) -
log2blksz), blkoff,
@@ -1613,7 +1627,8 @@ int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode)
return 1;
}
-long int read_allocated_block(struct ext2_inode *inode, int fileblock)
+long int read_allocated_block(struct ext2_inode *inode, int fileblock,
+ struct ext_block_cache *cache)
{
long int blknr;
int blksz;
@@ -1630,20 +1645,26 @@ long int read_allocated_block(struct ext2_inode *inode, int fileblock)
if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) {
long int startblock, endblock;
- char *buf = zalloc(blksz);
- if (!buf)
- return -ENOMEM;
+ struct ext_block_cache *c, cd;
struct ext4_extent_header *ext_block;
struct ext4_extent *extent;
int i;
+
+ if (cache) {
+ c = cache;
+ } else {
+ c = &cd;
+ ext_cache_init(c);
+ }
ext_block =
- ext4fs_get_extent_block(ext4fs_root, buf,
+ ext4fs_get_extent_block(ext4fs_root, c,
(struct ext4_extent_header *)
inode->b.blocks.dir_blocks,
fileblock, log2_blksz);
if (!ext_block) {
printf("invalid extent block\n");
- free(buf);
+ if (!cache)
+ ext_cache_fini(c);
return -EINVAL;
}
@@ -1655,19 +1676,22 @@ long int read_allocated_block(struct ext2_inode *inode, int fileblock)
if (startblock > fileblock) {
/* Sparse file */
- free(buf);
+ if (!cache)
+ ext_cache_fini(c);
return 0;
} else if (fileblock < endblock) {
start = le16_to_cpu(extent[i].ee_start_hi);
start = (start << 32) +
le32_to_cpu(extent[i].ee_start_lo);
- free(buf);
+ if (!cache)
+ ext_cache_fini(c);
return (fileblock - startblock) + start;
}
}
- free(buf);
+ if (!cache)
+ ext_cache_fini(c);
return 0;
}
diff --git a/fs/ext4/ext4_common.h b/fs/ext4/ext4_common.h
index 1ee81ab7ce..4dff1914d9 100644
--- a/fs/ext4/ext4_common.h
+++ b/fs/ext4/ext4_common.h
@@ -72,7 +72,7 @@ int ext4fs_iget(int inode_no, struct ext2_inode *inode);
void ext4fs_allocate_blocks(struct ext2_inode *file_inode,
unsigned int total_remaining_blocks,
unsigned int *total_no_of_block);
-void put_ext4(uint64_t off, void *buf, uint32_t size);
+void put_ext4(uint64_t off, const void *buf, uint32_t size);
struct ext2_block_group *ext4fs_get_group_descriptor
(const struct ext_filesystem *fs, uint32_t bg_idx);
uint64_t ext4fs_bg_get_block_id(const struct ext2_block_group *bg,
diff --git a/fs/ext4/ext4_journal.c b/fs/ext4/ext4_journal.c
index 148593da7f..6adbab93a6 100644
--- a/fs/ext4/ext4_journal.c
+++ b/fs/ext4/ext4_journal.c
@@ -347,7 +347,7 @@ void recover_transaction(int prev_desc_logical_no)
ext4fs_read_inode(ext4fs_root, EXT2_JOURNAL_INO,
(struct ext2_inode *)&inode_journal);
blknr = read_allocated_block((struct ext2_inode *)
- &inode_journal, i);
+ &inode_journal, i, NULL);
ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0, fs->blksz,
temp_buff);
p_jdb = (char *)temp_buff;
@@ -372,7 +372,7 @@ void recover_transaction(int prev_desc_logical_no)
be32_to_cpu(jdb->h_sequence)) == 0)
continue;
}
- blknr = read_allocated_block(&inode_journal, i);
+ blknr = read_allocated_block(&inode_journal, i, NULL);
ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0,
fs->blksz, metadata_buff);
put_ext4((uint64_t)((uint64_t)be32_to_cpu(tag->block) * (uint64_t)fs->blksz),
@@ -419,7 +419,8 @@ int ext4fs_check_journal_state(int recovery_flag)
}
ext4fs_read_inode(ext4fs_root, EXT2_JOURNAL_INO, &inode_journal);
- blknr = read_allocated_block(&inode_journal, EXT2_JOURNAL_SUPERBLOCK);
+ blknr = read_allocated_block(&inode_journal, EXT2_JOURNAL_SUPERBLOCK,
+ NULL);
ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0, fs->blksz,
temp_buff);
jsb = (struct journal_superblock_t *) temp_buff;
@@ -443,7 +444,7 @@ int ext4fs_check_journal_state(int recovery_flag)
i = be32_to_cpu(jsb->s_first);
while (1) {
- blknr = read_allocated_block(&inode_journal, i);
+ blknr = read_allocated_block(&inode_journal, i, NULL);
memset(temp_buff1, '\0', fs->blksz);
ext4fs_devread((lbaint_t)blknr * fs->sect_perblk,
0, fs->blksz, temp_buff1);
@@ -537,7 +538,7 @@ end:
ext4_read_superblock((char *)fs->sb);
blknr = read_allocated_block(&inode_journal,
- EXT2_JOURNAL_SUPERBLOCK);
+ EXT2_JOURNAL_SUPERBLOCK, NULL);
put_ext4((uint64_t) ((uint64_t)blknr * (uint64_t)fs->blksz),
(struct journal_superblock_t *)temp_buff,
(uint32_t) fs->blksz);
@@ -566,7 +567,7 @@ static void update_descriptor_block(long int blknr)
ext4fs_read_inode(ext4fs_root, EXT2_JOURNAL_INO, &inode_journal);
jsb_blknr = read_allocated_block(&inode_journal,
- EXT2_JOURNAL_SUPERBLOCK);
+ EXT2_JOURNAL_SUPERBLOCK, NULL);
ext4fs_devread((lbaint_t)jsb_blknr * fs->sect_perblk, 0, fs->blksz,
temp_buff);
jsb = (struct journal_superblock_t *) temp_buff;
@@ -618,7 +619,7 @@ static void update_commit_block(long int blknr)
ext4fs_read_inode(ext4fs_root, EXT2_JOURNAL_INO,
&inode_journal);
jsb_blknr = read_allocated_block(&inode_journal,
- EXT2_JOURNAL_SUPERBLOCK);
+ EXT2_JOURNAL_SUPERBLOCK, NULL);
ext4fs_devread((lbaint_t)jsb_blknr * fs->sect_perblk, 0, fs->blksz,
temp_buff);
jsb = (struct journal_superblock_t *) temp_buff;
@@ -645,16 +646,17 @@ void ext4fs_update_journal(void)
long int blknr;
int i;
ext4fs_read_inode(ext4fs_root, EXT2_JOURNAL_INO, &inode_journal);
- blknr = read_allocated_block(&inode_journal, jrnl_blk_idx++);
+ blknr = read_allocated_block(&inode_journal, jrnl_blk_idx++, NULL);
update_descriptor_block(blknr);
for (i = 0; i < MAX_JOURNAL_ENTRIES; i++) {
if (journal_ptr[i]->blknr == -1)
break;
- blknr = read_allocated_block(&inode_journal, jrnl_blk_idx++);
+ blknr = read_allocated_block(&inode_journal, jrnl_blk_idx++,
+ NULL);
put_ext4((uint64_t) ((uint64_t)blknr * (uint64_t)fs->blksz),
journal_ptr[i]->buf, fs->blksz);
}
- blknr = read_allocated_block(&inode_journal, jrnl_blk_idx++);
+ blknr = read_allocated_block(&inode_journal, jrnl_blk_idx++, NULL);
update_commit_block(blknr);
printf("update journal finished\n");
}
diff --git a/fs/ext4/ext4_write.c b/fs/ext4/ext4_write.c
index 4eb77c327e..504d23a895 100644
--- a/fs/ext4/ext4_write.c
+++ b/fs/ext4/ext4_write.c
@@ -465,6 +465,15 @@ static int ext4fs_delete_file(int inodeno)
if (le32_to_cpu(inode.size) % fs->blksz)
no_blocks++;
+ /*
+ * special case for symlinks whose target are small enough that
+ *it fits in struct ext2_inode.b.symlink: no block had been allocated
+ */
+ if ((le16_to_cpu(inode.mode) & S_IFLNK) &&
+ le32_to_cpu(inode.size) <= sizeof(inode.b.symlink)) {
+ no_blocks = 0;
+ }
+
if (le32_to_cpu(inode.flags) & EXT4_EXTENTS_FL) {
/* FIXME delete extent index blocks, i.e. eh_depth >= 1 */
struct ext4_extent_header *eh =
@@ -479,7 +488,7 @@ static int ext4fs_delete_file(int inodeno)
/* release data blocks */
for (i = 0; i < no_blocks; i++) {
- blknr = read_allocated_block(&inode, i);
+ blknr = read_allocated_block(&inode, i, NULL);
if (blknr == 0)
continue;
if (blknr < 0)
@@ -695,7 +704,7 @@ void ext4fs_deinit(void)
ext4fs_read_inode(ext4fs_root, EXT2_JOURNAL_INO,
&inode_journal);
blknr = read_allocated_block(&inode_journal,
- EXT2_JOURNAL_SUPERBLOCK);
+ EXT2_JOURNAL_SUPERBLOCK, NULL);
ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0, fs->blksz,
temp_buff);
jsb = (struct journal_superblock_t *)temp_buff;
@@ -752,7 +761,7 @@ void ext4fs_deinit(void)
* contigous sectors as ext4fs_read_file
*/
static int ext4fs_write_file(struct ext2_inode *file_inode,
- int pos, unsigned int len, char *buf)
+ int pos, unsigned int len, const char *buf)
{
int i;
int blockcnt;
@@ -764,7 +773,7 @@ static int ext4fs_write_file(struct ext2_inode *file_inode,
int delayed_start = 0;
int delayed_extent = 0;
int delayed_next = 0;
- char *delayed_buf = NULL;
+ const char *delayed_buf = NULL;
/* Adjust len so it we can't read past the end of the file. */
if (len > filesize)
@@ -776,7 +785,7 @@ static int ext4fs_write_file(struct ext2_inode *file_inode,
long int blknr;
int blockend = fs->blksz;
int skipfirst = 0;
- blknr = read_allocated_block(file_inode, i);
+ blknr = read_allocated_block(file_inode, i, NULL);
if (blknr <= 0)
return -1;
@@ -816,7 +825,6 @@ static int ext4fs_write_file(struct ext2_inode *file_inode,
(uint32_t) delayed_extent);
previous_block_number = -1;
}
- memset(buf, 0, fs->blksz - skipfirst);
}
buf += fs->blksz - skipfirst;
}
@@ -830,8 +838,8 @@ static int ext4fs_write_file(struct ext2_inode *file_inode,
return len;
}
-int ext4fs_write(const char *fname, unsigned char *buffer,
- unsigned long sizebytes)
+int ext4fs_write(const char *fname, const char *buffer,
+ unsigned long sizebytes, int type)
{
int ret = 0;
struct ext2_inode *file_inode = NULL;
@@ -854,8 +862,12 @@ int ext4fs_write(const char *fname, unsigned char *buffer,
struct ext2_block_group *bgd = NULL;
struct ext_filesystem *fs = get_fs();
ALLOC_CACHE_ALIGN_BUFFER(char, filename, 256);
+ bool store_link_in_inode = false;
memset(filename, 0x00, 256);
+ if (type != FILETYPE_REG && type != FILETYPE_SYMLINK)
+ return -1;
+
g_parent_inode = zalloc(fs->inodesz);
if (!g_parent_inode)
goto fail;
@@ -893,8 +905,16 @@ int ext4fs_write(const char *fname, unsigned char *buffer,
if (ret)
goto fail;
}
- /* calucalate how many blocks required */
- bytes_reqd_for_file = sizebytes;
+
+ /* calculate how many blocks required */
+ if (type == FILETYPE_SYMLINK &&
+ sizebytes <= sizeof(file_inode->b.symlink)) {
+ store_link_in_inode = true;
+ bytes_reqd_for_file = 0;
+ } else {
+ bytes_reqd_for_file = sizebytes;
+ }
+
blks_reqd_for_file = lldiv(bytes_reqd_for_file, fs->blksz);
if (do_div(bytes_reqd_for_file, fs->blksz) != 0) {
blks_reqd_for_file++;
@@ -907,7 +927,7 @@ int ext4fs_write(const char *fname, unsigned char *buffer,
goto fail;
}
- inodeno = ext4fs_update_parent_dentry(filename, FILETYPE_REG);
+ inodeno = ext4fs_update_parent_dentry(filename, type);
if (inodeno == -1)
goto fail;
/* prepare file inode */
@@ -915,14 +935,23 @@ int ext4fs_write(const char *fname, unsigned char *buffer,
if (!inode_buffer)
goto fail;
file_inode = (struct ext2_inode *)inode_buffer;
- file_inode->mode = cpu_to_le16(S_IFREG | S_IRWXU |
- S_IRGRP | S_IROTH | S_IXGRP | S_IXOTH);
+ file_inode->size = cpu_to_le32(sizebytes);
+ if (type == FILETYPE_SYMLINK) {
+ file_inode->mode = cpu_to_le16(S_IFLNK | S_IRWXU | S_IRWXG |
+ S_IRWXO);
+ if (store_link_in_inode) {
+ strncpy(file_inode->b.symlink, buffer, sizebytes);
+ sizebytes = 0;
+ }
+ } else {
+ file_inode->mode = cpu_to_le16(S_IFREG | S_IRWXU | S_IRGRP |
+ S_IROTH | S_IXGRP | S_IXOTH);
+ }
/* ToDo: Update correct time */
file_inode->mtime = cpu_to_le32(timestamp);
file_inode->atime = cpu_to_le32(timestamp);
file_inode->ctime = cpu_to_le32(timestamp);
file_inode->nlinks = cpu_to_le16(1);
- file_inode->size = cpu_to_le32(sizebytes);
/* Allocate data blocks */
ext4fs_allocate_blocks(file_inode, blocks_remaining,
@@ -949,7 +978,7 @@ int ext4fs_write(const char *fname, unsigned char *buffer,
if (ext4fs_put_metadata(temp_ptr, itable_blkno))
goto fail;
/* copy the file content into data blocks */
- if (ext4fs_write_file(file_inode, 0, sizebytes, (char *)buffer) == -1) {
+ if (ext4fs_write_file(file_inode, 0, sizebytes, buffer) == -1) {
printf("Error in copying content\n");
/* FIXME: Deallocate data blocks */
goto fail;
@@ -1014,7 +1043,7 @@ int ext4_write_file(const char *filename, void *buf, loff_t offset,
return -1;
}
- ret = ext4fs_write(filename, buf, len);
+ ret = ext4fs_write(filename, buf, len, FILETYPE_REG);
if (ret) {
printf("** Error ext4fs_write() **\n");
goto fail;
@@ -1029,3 +1058,8 @@ fail:
return -1;
}
+
+int ext4fs_create_link(const char *target, const char *fname)
+{
+ return ext4fs_write(fname, target, strlen(target), FILETYPE_SYMLINK);
+}
diff --git a/fs/ext4/ext4fs.c b/fs/ext4/ext4fs.c
index 2a28031d14..26db677a1f 100644
--- a/fs/ext4/ext4fs.c
+++ b/fs/ext4/ext4fs.c
@@ -62,6 +62,9 @@ int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
lbaint_t delayed_next = 0;
char *delayed_buf = NULL;
short status;
+ struct ext_block_cache cache;
+
+ ext_cache_init(&cache);
if (blocksize <= 0)
return -1;
@@ -77,9 +80,11 @@ int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
int blockoff = pos - (blocksize * i);
int blockend = blocksize;
int skipfirst = 0;
- blknr = read_allocated_block(&(node->inode), i);
- if (blknr < 0)
+ blknr = read_allocated_block(&node->inode, i, &cache);
+ if (blknr < 0) {
+ ext_cache_fini(&cache);
return -1;
+ }
blknr = blknr << log2_fs_blocksize;
@@ -109,8 +114,10 @@ int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
delayed_skipfirst,
delayed_extent,
delayed_buf);
- if (status == 0)
+ if (status == 0) {
+ ext_cache_fini(&cache);
return -1;
+ }
previous_block_number = blknr;
delayed_start = blknr;
delayed_extent = blockend;
@@ -136,8 +143,10 @@ int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
delayed_skipfirst,
delayed_extent,
delayed_buf);
- if (status == 0)
+ if (status == 0) {
+ ext_cache_fini(&cache);
return -1;
+ }
previous_block_number = -1;
}
/* Zero no more than `len' bytes. */
@@ -153,12 +162,15 @@ int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
status = ext4fs_devread(delayed_start,
delayed_skipfirst, delayed_extent,
delayed_buf);
- if (status == 0)
+ if (status == 0) {
+ ext_cache_fini(&cache);
return -1;
+ }
previous_block_number = -1;
}
*actread = len;
+ ext_cache_fini(&cache);
return 0;
}
@@ -252,3 +264,32 @@ int ext4fs_uuid(char *uuid_str)
return -ENOSYS;
#endif
}
+
+void ext_cache_init(struct ext_block_cache *cache)
+{
+ memset(cache, 0, sizeof(*cache));
+}
+
+void ext_cache_fini(struct ext_block_cache *cache)
+{
+ free(cache->buf);
+ ext_cache_init(cache);
+}
+
+int ext_cache_read(struct ext_block_cache *cache, lbaint_t block, int size)
+{
+ /* This could be more lenient, but this is simple and enough for now */
+ if (cache->buf && cache->block == block && cache->size == size)
+ return 1;
+ ext_cache_fini(cache);
+ cache->buf = malloc(size);
+ if (!cache->buf)
+ return 0;
+ if (!ext4fs_devread(block, 0, size, cache->buf)) {
+ free(cache->buf);
+ return 0;
+ }
+ cache->block = block;
+ cache->size = size;
+ return 1;
+}
generated by cgit (git 2.34.1) at 2025-09-05 21:21:51 +0000