NTFS: - Change {__,}ntfs_cluster_free() to also take an optional attribute

2.1.25-WIP

	- Change ntfs_map_runlist_nolock() and ntfs_attr_find_vcn_nolock() to

	  also take an optional attribute search context as argument.  This

	  allows calling these functions with the mft record mapped.  Update

	  all callers.

	- Change ntfs_map_runlist_nolock(), ntfs_attr_find_vcn_nolock() and

	  {__,}ntfs_cluster_free() to also take an optional attribute search

	  context as argument.  This allows calling these functions with the

	  mft record mapped.  Update all callers.

	- Fix potential deadlock in ntfs_mft_data_extend_allocation_nolock()

	  error handling by passing in the active search context when calling

	  ntfs_cluster_free().

2.1.24 - Lots of bug fixes and support more clean journal states.

 * @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

 * @is_rollback:	true if this is a rollback operation

 *

 * Free @count clusters starting at the cluster @start_vcn in the runlist

 * deallocated.  Thus, to completely free all clusters in a runlist, use

 * @start_vcn = 0 and @count = -1.

 *

 * 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 *.

 *

 * @is_rollback should always be FALSE, it is for internal use to rollback

 * errors.  You probably want to use ntfs_cluster_free() instead.

 *

 * Note, ntfs_cluster_free() does not modify the runlist at all, so the caller

 * has to deal with it later.

 * 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.

 *

 * 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.

 *	      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.

 */

s64 __ntfs_cluster_free(ntfs_inode *ni, const VCN start_vcn, s64 count,

		const BOOL is_rollback)

		ntfs_attr_search_ctx *ctx, const BOOL is_rollback)

{

	s64 delta, to_free, total_freed, real_freed;

	ntfs_volume *vol;

	total_freed = real_freed = 0;

	rl = ntfs_attr_find_vcn_nolock(ni, start_vcn, NULL);

	rl = ntfs_attr_find_vcn_nolock(ni, start_vcn, ctx);

	if (IS_ERR(rl)) {

		if (!is_rollback)

			ntfs_error(vol->sb, "Failed to find first runlist "

			/* Attempt to map runlist. */

			vcn = rl->vcn;

			rl = ntfs_attr_find_vcn_nolock(ni, vcn, NULL);

			rl = ntfs_attr_find_vcn_nolock(ni, vcn, ctx);

			if (IS_ERR(rl)) {

				err = PTR_ERR(rl);

				if (!is_rollback)

	 * If rollback fails, set the volume errors flag, emit an error

	 * message, and return the error code.

	 */

	delta = __ntfs_cluster_free(ni, start_vcn, total_freed, TRUE);

	delta = __ntfs_cluster_free(ni, start_vcn, total_freed, ctx, TRUE);

	if (delta < 0) {

		ntfs_error(vol->sb, "Failed to rollback (error %i).  Leaving "

				"inconsistent metadata!  Unmount and run "

#include <linux/fs.h>

#include "attrib.h"

#include "types.h"

#include "inode.h"

#include "runlist.h"

		const NTFS_CLUSTER_ALLOCATION_ZONES zone);

extern s64 __ntfs_cluster_free(ntfs_inode *ni, const VCN start_vcn,

		s64 count, const BOOL is_rollback);

		s64 count, ntfs_attr_search_ctx *ctx, const BOOL is_rollback);

/**

 * ntfs_cluster_free - free clusters on an ntfs volume

 * @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 ntfs inode @ni.

 * 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.

 *

 * 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.

 *	      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(ntfs_inode *ni, const VCN start_vcn,

		s64 count)

		s64 count, ntfs_attr_search_ctx *ctx)

{

	return __ntfs_cluster_free(ni, 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,

		NVolSetErrors(vol);

		return ret;

	}

	a = ctx->attr;

	a->data.non_resident.highest_vcn = cpu_to_sle64(old_last_vcn - 1);

	ctx->attr->data.non_resident.highest_vcn =

			cpu_to_sle64(old_last_vcn - 1);

undo_alloc:

	if (ntfs_cluster_free(mft_ni, old_last_vcn, -1) < 0) {

	if (ntfs_cluster_free(mft_ni, old_last_vcn, -1, ctx) < 0) {

		ntfs_error(vol->sb, "Failed to free clusters from mft data "

				"attribute.%s", es);

		NVolSetErrors(vol);

	}

	a = ctx->attr;

	if (ntfs_rl_truncate_nolock(vol, &mft_ni->runlist, old_last_vcn)) {

		ntfs_error(vol->sb, "Failed to truncate mft data attribute "

				"runlist.%s", es);

		NVolSetErrors(vol);

	}

	if (mp_rebuilt) {

	if (mp_rebuilt && !IS_ERR(ctx->mrec)) {

		if (ntfs_mapping_pairs_build(vol, (u8*)a + le16_to_cpu(

				a->data.non_resident.mapping_pairs_offset),

				old_alen - le16_to_cpu(

		}

		flush_dcache_mft_record_page(ctx->ntfs_ino);

		mark_mft_record_dirty(ctx->ntfs_ino);

	} else if (IS_ERR(ctx->mrec)) {

		ntfs_error(vol->sb, "Failed to restore attribute search "

				"context.%s", es);

		NVolSetErrors(vol);

	}

	if (ctx)

		ntfs_attr_put_search_ctx(ctx);