fs: fat: reuse deleted directory entries

When creating new directory entries try to reuse entries marked as deleted.

In fill_dir_slot() do not allocate new clusters as this has already been
done in fat_find_empty_dentries().

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c
index d560b94..a029ef8 100644 (file)
--- a/fs/fat/fat_write.c
+++ b/fs/fat/fat_write.c
@@ -258,7 +258,7 @@ static int flush_dirty_fat_buffer(fsdata *mydata)
  * @count:     number of directory entries to find
  * Return:     0 on success or negative error number
  */
-static int __maybe_unused fat_find_empty_dentries(fat_itr *itr, int count)
+static int fat_find_empty_dentries(fat_itr *itr, int count)
 {
        unsigned int cluster;
        dir_entry *dent;
@@ -421,11 +421,9 @@ fill_dir_slot(fat_itr *itr, const char *l_name, const char *shortname)
                if (itr->remaining == 0)
                        flush_dir(itr);
 
-               /* allocate a cluster for more entries */
-               if (!next_dent(itr) && !itr->dent)
-                       if ((itr->is_root && itr->fsdata->fatsize != 32) ||
-                           new_dir_table(itr))
-                               return -EIO;
+               next_dent(itr);
+               if (!itr->dent)
+                       return -EIO;
        }
 
        return 0;
@@ -1339,6 +1337,7 @@ int file_fat_write_at(const char *filename, loff_t pos, void *buffer,
        } else {
                /* Create a new file */
                char shortname[SHORT_NAME_SIZE];
+               int ndent;
 
                if (itr->is_root) {
                        /* root dir cannot have "." or ".." */
@@ -1362,10 +1361,15 @@ int file_fat_write_at(const char *filename, loff_t pos, void *buffer,
                }
 
                /* Check if long name is needed */
-               ret = set_name(itr, filename, shortname);
-               if (ret < 0)
+               ndent = set_name(itr, filename, shortname);
+               if (ndent < 0) {
+                       ret = ndent;
+                       goto exit;
+               }
+               ret = fat_find_empty_dentries(itr, ndent);
+               if (ret)
                        goto exit;
-               if (ret > 1) {
+               if (ndent > 1) {
                        /* Set long name entries */
                        ret = fill_dir_slot(itr, filename, shortname);
                        if (ret)
@@ -1607,6 +1611,7 @@ int fat_mkdir(const char *new_dirname)
                goto exit;
        } else {
                char shortname[SHORT_NAME_SIZE];
+               int ndent;
 
                if (itr->is_root) {
                        /* root dir cannot have "." or ".." */
@@ -1624,10 +1629,15 @@ int fat_mkdir(const char *new_dirname)
                }
 
                /* Check if long name is needed */
-               ret = set_name(itr, dirname, shortname);
-               if (ret < 0)
+               ndent = set_name(itr, dirname, shortname);
+               if (ndent < 0) {
+                       ret = ndent;
+                       goto exit;
+               }
+               ret = fat_find_empty_dentries(itr, ndent);
+               if (ret)
                        goto exit;
-               if (ret > 1) {
+               if (ndent > 1) {
                        /* Set long name entries */
                        ret = fill_dir_slot(itr, dirname, shortname);
                        if (ret)