yaffsfs: Allocate directory searches from a table rather than via malloc.

[yaffs2.git] / direct / yaffsfs.c

diff --git a/direct/yaffsfs.c b/direct/yaffsfs.c
index 9ef19bff447227f7ff6e7b535a5372d3a32cb706..2110fe8f4ef1a621ecc5e15d7cb94431e1015e2e 100644 (file)
--- a/direct/yaffsfs.c
+++ b/direct/yaffsfs.c
@@ -17,7 +17,7 @@
 #include "yportenv.h"
 #include "yaffs_trace.h"
 
-#include <string.h> /* for memset */
+#include "string.h"
 
 #define YAFFSFS_MAX_SYMLINK_DEREFERENCES 5
 
@@ -83,6 +83,20 @@ typedef struct {
        short int useCount;
 } yaffsfs_Handle;
 
+
+typedef struct
+{
+       yaffs_dirent de;                /* directory entry being used by this dsc */
+       YCHAR name[NAME_MAX+1];         /* name of directory being searched */
+        struct yaffs_obj *dirObj;           /* ptr to directory being searched */
+        struct yaffs_obj *nextReturn;       /* obj to be returned by next readddir */
+        struct list_head others;
+        int offset:20;
+        unsigned inUse:1;
+} yaffsfs_DirectorySearchContext;
+
+
+static yaffsfs_DirectorySearchContext yaffsfs_dsc[YAFFSFS_N_DSC];
 static yaffsfs_Inode yaffsfs_inode[YAFFSFS_N_HANDLES];
 static yaffsfs_FileDes yaffsfs_fd[YAFFSFS_N_HANDLES];
 static yaffsfs_Handle yaffsfs_handle[YAFFSFS_N_HANDLES];
@@ -112,9 +126,10 @@ static void yaffsfs_InitHandles(void)
        if(yaffsfs_handlesInitialised)
                 return;
 
-       memset(yaffsfs_inode,0,sizeof(yaffsfs_inode));
-       memset(yaffsfs_fd,0,sizeof(yaffsfs_fd));
-       memset(yaffsfs_handle,0,sizeof(yaffsfs_handle));
+       memset(yaffsfs_inode, 0, sizeof(yaffsfs_inode));
+       memset(yaffsfs_fd, 0, sizeof(yaffsfs_fd));
+       memset(yaffsfs_handle, 0, sizeof(yaffsfs_handle));
+       memset(yaffsfs_dsc, 0, sizeof(yaffsfs_dsc));
 
        for(i = 0; i < YAFFSFS_N_HANDLES; i++)
                yaffsfs_fd[i].inodeId = -1;
@@ -381,7 +396,7 @@ static void yaffsfs_BreakDeviceHandles(struct yaffs_dev *dev)
  *  Stuff to handle names.
  */
 #ifdef CONFIG_YAFFS_CASE_INSENSITIVE
- 
+
 static int yaffs_toupper(YCHAR a)
 {
        if(a >= 'a' && a <= 'z')
@@ -2768,29 +2783,29 @@ void yaffs_remove_device(struct yaffs_dev *dev)
        list_del_init(&dev->dev_list);
 }
 
+/* Functions to iterate through devices. NB Use with extreme care! */
 
+static struct list_head *dev_iterator;
+void yaffs_dev_rewind(void)
+{
+       dev_iterator = yaffsfs_deviceList.next;
+}
 
+struct yaffs_dev *yaffs_next_dev(void)
+{
+       struct yaffs_dev *retval;
 
-/* Directory search stuff. */
-
-/*
- * Directory search context
- *
- * NB this is an opaque structure.
- */
-
+       if(!dev_iterator)
+               return NULL;
+       if(dev_iterator == &yaffsfs_deviceList)
+               return NULL;
 
-typedef struct
-{
-       u32 magic;
-       yaffs_dirent de;                /* directory entry being used by this dsc */
-       YCHAR name[NAME_MAX+1];         /* name of directory being searched */
-        struct yaffs_obj *dirObj;           /* ptr to directory being searched */
-        struct yaffs_obj *nextReturn;       /* obj to be returned by next readddir */
-        int offset;
-        struct list_head others;
-} yaffsfs_DirectorySearchContext;
+       retval = list_entry(dev_iterator, struct yaffs_dev, dev_list);
+       dev_iterator = dev_iterator->next;
+       return retval;
+}
 
+/* Directory search stuff. */
 
 
 static struct list_head search_contexts;
@@ -2891,13 +2906,18 @@ yaffs_DIR *yaffs_opendir(const YCHAR *dirname)
        else if(obj->variant_type != YAFFS_OBJECT_TYPE_DIRECTORY)
                yaffsfs_SetError(-ENOTDIR);
        else {
+               int i;
+
+               for(i = 0, dsc = NULL; i < YAFFSFS_N_DSC && !dsc; i++) {
+                       if(!yaffsfs_dsc[i].inUse)
+                               dsc = & yaffsfs_dsc[i];
+               }
 
-               dsc = kmalloc(sizeof(yaffsfs_DirectorySearchContext), 0);
                dir = (yaffs_DIR *)dsc;
 
                if(dsc){
                        memset(dsc,0,sizeof(yaffsfs_DirectorySearchContext));
-                        dsc->magic = YAFFS_MAGIC;
+                        dsc->inUse = 1;
                         dsc->dirObj = obj;
                         yaffs_strncpy(dsc->name,dirname,NAME_MAX);
                         INIT_LIST_HEAD(&dsc->others);
@@ -2923,7 +2943,7 @@ struct yaffs_dirent *yaffs_readdir(yaffs_DIR *dirp)
 
        yaffsfs_Lock();
 
-       if(dsc && dsc->magic == YAFFS_MAGIC){
+       if(dsc && dsc->inUse){
                yaffsfs_SetError(0);
                if(dsc->nextReturn){
                        dsc->de.d_ino = yaffs_get_equivalent_obj(dsc->nextReturn)->obj_id;
@@ -2972,9 +2992,8 @@ int yaffs_closedir(yaffs_DIR *dirp)
        }
 
         yaffsfs_Lock();
-        dsc->magic = 0;
+        dsc->inUse = 0;
         list_del(&dsc->others); /* unhook from list */
-        kfree(dsc);
         yaffsfs_Unlock();
         return 0;
 }