Hi Marek,
The code for handing file overwrite incorrectly assumed that the file on disk is always contiguous. This resulted in corrupting disk structure every time when write to existing fragmented file happened. Fix this by adding proper check for cluster discontinuity and adjust chunk size on each partial write.
Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com
fs/fat/fat_write.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c index 729cf39630d..6cfa5b45652 100644 --- a/fs/fat/fat_write.c +++ b/fs/fat/fat_write.c @@ -794,6 +794,8 @@ set_contents(fsdata *mydata, dir_entry *dentptr, loff_t pos, __u8 *buffer, newclust = get_fatent(mydata, endclust);
if ((newclust - 1) != endclust)break; if (IS_LAST_CLUST(newclust, mydata->fatsize)) break; if (CHECK_CLUST(newclust, mydata->fatsize)) {@@ -811,7 +813,7 @@ set_contents(fsdata *mydata, dir_entry *dentptr, loff_t pos, __u8 *buffer, offset = 0; else offset = pos - cur_pos;
wsize = min(cur_pos + actsize, filesize) - pos;
wsize = min_t(unsigned long long, actsize, filesize
- cur_pos); if (get_set_cluster(mydata, curclust, offset, buffer, wsize, &actsize)) { printf("Error get-and-setting cluster\n");
@@ -824,8 +826,6 @@ set_contents(fsdata *mydata, dir_entry *dentptr, loff_t pos, __u8 *buffer, if (filesize <= cur_pos) break;
/* CHECK: newclust = get_fatent(mydata, endclust); */- if (IS_LAST_CLUST(newclust, mydata->fatsize)) /* no more clusters */ break;
Reviewed-by: Lukasz Majewski lukma@denx.de
Best regards,
Lukasz Majewski
--
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