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Diffstat (limited to 'fs/ext4/ext4_write.c')
-rw-r--r--fs/ext4/ext4_write.c66
1 files changed, 50 insertions, 16 deletions
diff --git a/fs/ext4/ext4_write.c b/fs/ext4/ext4_write.c
index 4eb77c327ef..504d23a8956 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);
+}
generated by cgit v1.2.3 (git 2.0.4) at 2025-07-26 06:08:03 +0000