Add the ability to specify a reserved space size when making filesystems.
If you specify a negative length when making a filesystem, then the
filesystem size is the size of the partiton (or image file) minus
the absolute value of the negative length specified.
Change-Id: I53e3b6de2ea692f4678682c3f49ff36429d9ad31
diff --git a/ext4_utils/ext4_utils.c b/ext4_utils/ext4_utils.c
index 1804e4b..bdf2a74 100644
--- a/ext4_utils/ext4_utils.c
+++ b/ext4_utils/ext4_utils.c
@@ -103,7 +103,7 @@
for_each_data_block(count_data_block, count_file_block, &count_chunks);
- if (count_chunks.cur_ptr != info.len)
+ if (count_chunks.cur_ptr != (u64) info.len)
count_chunks.chunks++;
return count_chunks.chunks;
@@ -442,17 +442,29 @@
{
struct stat buf;
int ret;
+ u64 reserve_len = 0;
+ s64 computed_size;
ret = stat(filename, &buf);
if (ret)
return 0;
+ if (info.len < 0)
+ reserve_len = -info.len;
+
if (S_ISREG(buf.st_mode))
- return buf.st_size;
+ computed_size = buf.st_size - reserve_len;
else if (S_ISBLK(buf.st_mode))
- return get_block_device_size(filename);
+ computed_size = get_block_device_size(filename) - reserve_len;
else
- return 0;
+ computed_size = 0;
+
+ if (computed_size < 0) {
+ warn("Computed filesystem size less than 0");
+ computed_size = 0;
+ }
+
+ return computed_size;
}
u64 parse_num(const char *arg)
diff --git a/ext4_utils/ext4_utils.h b/ext4_utils/ext4_utils.h
index 8f3a64d..b770294 100644
--- a/ext4_utils/ext4_utils.h
+++ b/ext4_utils/ext4_utils.h
@@ -76,6 +76,7 @@
#define __u8 u8
typedef unsigned long long u64;
+typedef signed long long s64;
typedef unsigned int u32;
typedef unsigned short int u16;
typedef unsigned char u8;
@@ -94,7 +95,9 @@
};
struct fs_info {
- u64 len;
+ s64 len; /* If set to 0, ask the block device for the size,
+ * if less than 0, reserve that much space at the
+ * end of the partition, else use the size given. */
u32 block_size;
u32 blocks_per_group;
u32 inodes_per_group;
diff --git a/ext4_utils/make_ext4fs.c b/ext4_utils/make_ext4fs.c
index 3fee133..a366a37 100644
--- a/ext4_utils/make_ext4fs.c
+++ b/ext4_utils/make_ext4fs.c
@@ -249,7 +249,7 @@
u32 root_inode_num;
u16 root_mode;
- if (info.len == 0)
+ if (info.len <= 0)
info.len = get_file_size(filename);
if (info.len <= 0) {
diff --git a/ext4_utils/output_file.c b/ext4_utils/output_file.c
index 66550d5..c1997b6 100644
--- a/ext4_utils/output_file.c
+++ b/ext4_utils/output_file.c
@@ -333,7 +333,7 @@
{
int ret;
- if (len > info.len) {
+ if (len > (u64) info.len) {
error("attempted to pad file %llu bytes past end of filesystem",
len - info.len);
return;
@@ -370,7 +370,7 @@
{
int ret;
- if (off + len > info.len) {
+ if (off + len > (u64) info.len) {
error("attempted to write block %llu past end of filesystem",
off + len - info.len);
return;
@@ -397,7 +397,7 @@
off64_t aligned_offset;
int aligned_diff;
- if (off + len >= info.len) {
+ if (off + len >= (u64) info.len) {
error("attempted to write block %llu past end of filesystem",
off + len - info.len);
return;