ref: 0c4612983ad9651b72390f4525f52234e5062a8f
parent: 35c79ba9d1f9d3dc86a9da5bd8273e8e74d73108
author: gkostka <[email protected]>
date: Mon Oct 19 16:52:12 EDT 2015
Fix fwrite function If block allocation fail some data could be flushed to file (when alocated blocks was ordered). Node size should be updated after ext4_fs_append_inode_block fails.
--- a/lwext4/ext4.c
+++ b/lwext4/ext4.c
@@ -1254,11 +1254,15 @@
int ext4_fread(ext4_file *f, void *buf, size_t size, size_t *rcnt)
{- uint32_t u;
- ext4_fsblk_t fblock;
- uint32_t fblock_cnt;
- uint32_t sblock;
+ uint32_t unaligned;
+ uint32_t iblock_idx;
+ uint32_t iblock_last;
uint32_t block_size;
+
+ ext4_fsblk_t fblock;
+ ext4_fsblk_t fblock_start;
+ uint32_t fblock_count;
+
uint8_t *u8_buf = buf;
int r;
struct ext4_block b;
@@ -1288,9 +1292,11 @@
block_size = ext4_sb_get_block_size(&f->mp->fs.sb);
size = size > (f->fsize - f->fpos) ? (f->fsize - f->fpos) : size;
- sblock = (f->fpos) / block_size;
- u = (f->fpos) % block_size;
+ iblock_idx = (f->fpos) / block_size;
+ iblock_last = (f->fpos + size) / block_size;
+ unaligned = (f->fpos) % block_size;
+
/*If the size of symlink is smaller than 60 bytes*/
if (ext4_inode_is_type(&f->mp->fs.sb, ref.inode, EXT4_INODE_MODE_SOFTLINK)
&& f->fsize < sizeof(ref.inode->blocks)
@@ -1297,10 +1303,10 @@
&& !ext4_inode_get_blocks_count(&f->mp->fs.sb, ref.inode)) {char *content = (char *)ref.inode->blocks;
if (f->fpos < f->fsize) {- r = (u + size > f->fsize)
- ?(f->fsize - u)
+ r = (unaligned + size > f->fsize)
+ ?(f->fsize - unaligned)
:(size);
- memcpy(buf, content + u, r);
+ memcpy(buf, content + unaligned, r);
if (rcnt)
*rcnt = r;
@@ -1315,12 +1321,10 @@
goto Finish;
}
- if (u) {-
- uint32_t ll = size > (block_size - u) ? (block_size - u) : size;
-
- r = ext4_fs_get_inode_data_block_index(&ref,
- sblock, &fblock,
+ if (unaligned) {+ uint32_t l = size > (block_size - unaligned) ?
+ (block_size - unaligned) : size;
+ r = ext4_fs_get_inode_data_block_index(&ref, iblock_idx, &fblock,
true);
if (r != EOK)
goto Finish;
@@ -1331,7 +1335,7 @@
if (r != EOK)
goto Finish;
- memcpy(u8_buf, b.data + u, ll);
+ memcpy(u8_buf, b.data + unaligned, l);
r = ext4_block_set(f->mp->fs.bdev, &b);
if (r != EOK)
@@ -1338,49 +1342,58 @@
goto Finish;
} else {/* Yes, we do. */
- memset(u8_buf, 0, ll);
+ memset(u8_buf, 0, l);
}
- u8_buf += ll;
- size -= ll;
- f->fpos += ll;
+ u8_buf += l;
+ size -= l;
+ f->fpos += l;
if (rcnt)
- *rcnt += ll;
+ *rcnt += l;
- sblock++;
+ iblock_idx++;
}
- fblock_cnt = 0;
+ fblock_start = 0;
+ fblock_count = 0;
while (size >= block_size) {+ while (iblock_idx < iblock_last) {+ r = ext4_fs_get_inode_data_block_index(&ref, iblock_idx,
+ &fblock, true);
+ if (r != EOK)
+ goto Finish;
- r = ext4_fs_get_inode_data_block_index(&ref, sblock,
- &fblock,
- true);
- if (r != EOK)
- goto Finish;
+ iblock_idx++;
- sblock++;
- fblock_cnt = 1;
+ if (!fblock_start)
+ fblock_start = fblock;
- r = ext4_blocks_get_direct(f->mp->fs.bdev, u8_buf, fblock,
- fblock_cnt);
+ if ((fblock_start + fblock_count) != fblock)
+ break;
+
+ fblock_count++;
+ }
+
+ r = ext4_blocks_get_direct(f->mp->fs.bdev, u8_buf, fblock_start,
+ fblock_count);
if (r != EOK)
goto Finish;
- size -= block_size * fblock_cnt;
- u8_buf += block_size * fblock_cnt;
- f->fpos += block_size * fblock_cnt;
+ size -= block_size * fblock_count;
+ u8_buf += block_size * fblock_count;
+ f->fpos += block_size * fblock_count;
if (rcnt)
- *rcnt += block_size * fblock_cnt;
+ *rcnt += block_size * fblock_count;
+ fblock_start = fblock;
+ fblock_count = 1;
}
if (size) {- r = ext4_fs_get_inode_data_block_index(&ref,
- sblock, &fblock,
- true);
+ r = ext4_fs_get_inode_data_block_index(&ref, iblock_idx, &fblock,
+ true);
if (r != EOK)
goto Finish;
@@ -1408,18 +1421,20 @@
int ext4_fwrite(ext4_file *f, const void *buf, size_t size, size_t *wcnt)
{- uint32_t u;
- ext4_fsblk_t fblock;
-
- uint32_t sblock;
- uint32_t file_blocks;
+ uint32_t unaligned;
+ uint32_t iblock_idx;
+ uint32_t iblock_last;
+ uint32_t ifile_blocks;
uint32_t block_size;
- uint32_t fblock_cnt;
+ uint32_t fblock_count;
+ ext4_fsblk_t fblock;
+ ext4_fsblk_t fblock_start;
+
struct ext4_block b;
struct ext4_inode_ref ref;
const uint8_t *u8_buf = buf;
- int r;
+ int r, rr = EOK;
ext4_assert(f && f->mp);
@@ -1442,19 +1457,18 @@
/*Sync file size*/
f->fsize = ext4_inode_get_size(&f->mp->fs.sb, ref.inode);
-
block_size = ext4_sb_get_block_size(&f->mp->fs.sb);
- file_blocks = (f->fsize + block_size - 1) / block_size;
+ iblock_last = (f->fpos + size) / block_size;
+ iblock_idx = (f->fpos) / block_size;
+ ifile_blocks = (f->fsize + block_size - 1) / block_size;
- sblock = (f->fpos) / block_size;
+ unaligned = (f->fpos) % block_size;
- u = (f->fpos) % block_size;
-
- if (u) {- uint32_t ll = size > (block_size - u) ? (block_size - u) : size;
-
- r = ext4_fs_init_inode_data_block_index(&ref, sblock, &fblock);
+ if (unaligned) {+ uint32_t l = size > (block_size - unaligned) ?
+ (block_size - unaligned) : size;
+ r = ext4_fs_init_inode_data_block_index(&ref, iblock_idx, &fblock);
if (r != EOK)
goto Finish;
@@ -1462,7 +1476,7 @@
if (r != EOK)
goto Finish;
- memcpy(b.data + u, u8_buf, ll);
+ memcpy(b.data + unaligned, u8_buf, l);
b.dirty = true;
r = ext4_block_set(f->mp->fs.bdev, &b);
@@ -1469,14 +1483,14 @@
if (r != EOK)
goto Finish;
- u8_buf += ll;
- size -= ll;
- f->fpos += ll;
+ u8_buf += l;
+ size -= l;
+ f->fpos += l;
if (wcnt)
- *wcnt += ll;
+ *wcnt += l;
- sblock++;
+ iblock_idx++;
}
/*Start write back cache mode.*/
@@ -1484,36 +1498,63 @@
if (r != EOK)
goto Finish;
- fblock_cnt = 0;
+ fblock_start = 0;
+ fblock_count = 0;
while (size >= block_size) {- if (sblock < file_blocks) {- r = ext4_fs_init_inode_data_block_index(
- &ref, sblock, &fblock);
- if (r != EOK)
+ while (iblock_idx < iblock_last) {+ if (iblock_idx < ifile_blocks) {+ r = ext4_fs_init_inode_data_block_index(
+ &ref, iblock_idx, &fblock);
+ if (r != EOK)
+ goto Finish;
+ } else {+ rr = ext4_fs_append_inode_block(&ref, &fblock,
+ &iblock_idx);
+ if (rr != EOK) {+ /* Unable to append more blocks. But some
+ * block might be allocated already.
+ * */
+ break;
+ }
+ }
+
+ iblock_idx++;
+
+ if (!fblock_start) {+ fblock_start = fblock;
+ }
+
+ if ((fblock_start + fblock_count) != fblock)
break;
- } else {- r = ext4_fs_append_inode_block(&ref, &fblock,
- &sblock);
- if (r != EOK)
- break;
+
+ fblock_count++;
}
- sblock++;
- fblock_cnt = 1;
+ if (rr != EOK) {+ if (fblock_count == 1) {+ /*ext4_fs_append_inode_block has failed and no
+ * more blocks shold be written. But node size
+ * should be updated.*/
+ r = rr;
+ goto out_fsize;
+ }
+ }
- r = ext4_blocks_set_direct(f->mp->fs.bdev, u8_buf, fblock,
- fblock_cnt);
+ r = ext4_blocks_set_direct(f->mp->fs.bdev, u8_buf, fblock_start,
+ fblock_count);
if (r != EOK)
break;
- size -= block_size * fblock_cnt;
- u8_buf += block_size * fblock_cnt;
- f->fpos += block_size * fblock_cnt;
+ size -= block_size * fblock_count;
+ u8_buf += block_size * fblock_count;
+ f->fpos += block_size * fblock_count;
if (wcnt)
- *wcnt += block_size * fblock_cnt;
+ *wcnt += block_size * fblock_count;
+ fblock_start = fblock;
+ fblock_count = 1;
}
/*Stop write back cache mode*/
@@ -1523,15 +1564,16 @@
goto Finish;
if (size) {- if (sblock < file_blocks) {- r = ext4_fs_init_inode_data_block_index(&ref, sblock,
+ if (iblock_idx < ifile_blocks) {+ r = ext4_fs_init_inode_data_block_index(&ref, iblock_idx,
&fblock);
if (r != EOK)
goto Finish;
} else {- r = ext4_fs_append_inode_block(&ref, &fblock, &sblock);
+ r = ext4_fs_append_inode_block(&ref, &fblock, &iblock_idx);
if (r != EOK)
- goto Finish;
+ /*Node size sholud be updated.*/
+ goto out_fsize;
}
r = ext4_block_get(f->mp->fs.bdev, &b, fblock);
@@ -1551,6 +1593,7 @@
*wcnt += size;
}
+out_fsize:
if (f->fpos > f->fsize) {f->fsize = f->fpos;
ext4_inode_set_size(ref.inode, f->fsize);