X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=fs%2Fntfs%2Flcnalloc.h;h=72cbca7003b2de3ee54ffe4a358efac9e767f090;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=4cac1c024af60809142a43b6431f380aff3d05ee;hpb=cee37fe97739d85991964371c1f3a745c00dd236;p=linux-2.6.git

diff --git a/fs/ntfs/lcnalloc.h b/fs/ntfs/lcnalloc.h
index 4cac1c024..72cbca700 100644
--- a/fs/ntfs/lcnalloc.h
+++ b/fs/ntfs/lcnalloc.h
@@ -2,7 +2,7 @@
  * lcnalloc.h - Exports for NTFS kernel cluster (de)allocation.  Part of the
  *		Linux-NTFS project.
  *
- * Copyright (c) 2004 Anton Altaparmakov
+ * Copyright (c) 2004-2005 Anton Altaparmakov
  *
  * This program/include file is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as published
@@ -27,7 +27,9 @@
 
 #include <linux/fs.h>
 
+#include "attrib.h"
 #include "types.h"
+#include "inode.h"
 #include "runlist.h"
 #include "volume.h"
 
@@ -40,43 +42,72 @@ typedef enum {
 
 extern runlist_element *ntfs_cluster_alloc(ntfs_volume *vol,
 		const VCN start_vcn, const s64 count, const LCN start_lcn,
-		const NTFS_CLUSTER_ALLOCATION_ZONES zone);
+		const NTFS_CLUSTER_ALLOCATION_ZONES zone,
+		const BOOL is_extension);
 
-extern s64 __ntfs_cluster_free(struct inode *vi, const VCN start_vcn,
-		s64 count, const BOOL is_rollback);
+extern s64 __ntfs_cluster_free(ntfs_inode *ni, const VCN start_vcn,
+		s64 count, ntfs_attr_search_ctx *ctx, const BOOL is_rollback);
 
 /**
  * ntfs_cluster_free - free clusters on an ntfs volume
- * @vi:		vfs inode whose runlist describes the clusters to free
- * @start_vcn:	vcn in the runlist of @vi at which to start freeing clusters
+ * @ni:		ntfs inode whose runlist describes the clusters to free
+ * @start_vcn:	vcn in the runlist of @ni at which to start freeing clusters
  * @count:	number of clusters to free or -1 for all clusters
+ * @ctx:	active attribute search context if present or NULL if not
  *
  * Free @count clusters starting at the cluster @start_vcn in the runlist
- * described by the vfs inode @vi.
+ * described by the ntfs inode @ni.
  *
  * If @count is -1, all clusters from @start_vcn to the end of the runlist are
  * deallocated.  Thus, to completely free all clusters in a runlist, use
  * @start_vcn = 0 and @count = -1.
  *
- * Note, ntfs_cluster_free() does not modify the runlist at all, so the caller
- * has to deal with it later.
+ * If @ctx is specified, it is an active search context of @ni and its base mft
+ * record.  This is needed when ntfs_cluster_free() encounters unmapped runlist
+ * fragments and allows their mapping.  If you do not have the mft record
+ * mapped, you can specify @ctx as NULL and ntfs_cluster_free() will perform
+ * the necessary mapping and unmapping.
+ *
+ * Note, ntfs_cluster_free() saves the state of @ctx on entry and restores it
+ * before returning.  Thus, @ctx will be left pointing to the same attribute on
+ * return as on entry.  However, the actual pointers in @ctx may point to
+ * different memory locations on return, so you must remember to reset any
+ * cached pointers from the @ctx, i.e. after the call to ntfs_cluster_free(),
+ * you will probably want to do:
+ *	m = ctx->mrec;
+ *	a = ctx->attr;
+ * Assuming you cache ctx->attr in a variable @a of type ATTR_RECORD * and that
+ * you cache ctx->mrec in a variable @m of type MFT_RECORD *.
+ *
+ * Note, ntfs_cluster_free() does not modify the runlist, so you have to remove
+ * from the runlist or mark sparse the freed runs later.
  *
  * Return the number of deallocated clusters (not counting sparse ones) on
  * success and -errno on error.
  *
- * Locking: - The runlist described by @vi must be unlocked on entry and is
- *	      unlocked on return.
- *	    - This function takes the runlist lock of @vi for reading and
- *	      sometimes for writing and sometimes modifies the runlist.
+ * WARNING: If @ctx is supplied, regardless of whether success or failure is
+ *	    returned, you need to check IS_ERR(@ctx->mrec) and if TRUE the @ctx
+ *	    is no longer valid, i.e. you need to either call
+ *	    ntfs_attr_reinit_search_ctx() or ntfs_attr_put_search_ctx() on it.
+ *	    In that case PTR_ERR(@ctx->mrec) will give you the error code for
+ *	    why the mapping of the old inode failed.
+ *
+ * Locking: - The runlist described by @ni must be locked for writing on entry
+ *	      and is locked on return.  Note the runlist may be modified when
+ *	      needed runlist fragments need to be mapped.
  *	    - The volume lcn bitmap must be unlocked on entry and is unlocked
  *	      on return.
  *	    - This function takes the volume lcn bitmap lock for writing and
  *	      modifies the bitmap contents.
+ *	    - If @ctx is NULL, the base mft record of @ni must not be mapped on
+ *	      entry and it will be left unmapped on return.
+ *	    - If @ctx is not NULL, the base mft record must be mapped on entry
+ *	      and it will be left mapped on return.
  */
-static inline s64 ntfs_cluster_free(struct inode *vi, const VCN start_vcn,
-		s64 count)
+static inline s64 ntfs_cluster_free(ntfs_inode *ni, const VCN start_vcn,
+		s64 count, ntfs_attr_search_ctx *ctx)
 {
-	return __ntfs_cluster_free(vi, start_vcn, count, FALSE);
+	return __ntfs_cluster_free(ni, start_vcn, count, ctx, FALSE);
 }
 
 extern int ntfs_cluster_free_from_rl_nolock(ntfs_volume *vol,
@@ -93,8 +124,10 @@ extern int ntfs_cluster_free_from_rl_nolock(ntfs_volume *vol,
  *
  * Return 0 on success and -errno on error.
  *
- * Locking: This function takes the volume lcn bitmap lock for writing and
- *	    modifies the bitmap contents.
+ * Locking: - This function takes the volume lcn bitmap lock for writing and
+ *	      modifies the bitmap contents.
+ *	    - The caller must have locked the runlist @rl for reading or
+ *	      writing.
  */
 static inline int ntfs_cluster_free_from_rl(ntfs_volume *vol,
 		const runlist_element *rl)