Commit 69b41e3c authored by Anton Altaparmakov's avatar Anton Altaparmakov
Browse files

NTFS: Change ntfs_attr_find_vcn_nolock() to also take an optional attribute 


      search context as argument.  This allows calling it with the mft
      record mapped.  Update all callers.

Signed-off-by: default avatarAnton Altaparmakov <aia21@cantab.net>
parent fd9d6367

fs/ntfs/ChangeLog

+4 −2
Original line number Diff line number Diff line
@@ -24,8 +24,10 @@ ToDo/Notes: 


2.1.25-WIP



	- Change ntfs_map_runlist_nolock() to also take an optional attribute

	  search context.  This allows calling it with the mft record mapped.

	- 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.



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

fs/ntfs/attrib.c

+48 −36
Original line number Diff line number Diff line
@@ -408,7 +408,7 @@ LCN ntfs_attr_vcn_to_lcn_nolock(ntfs_inode *ni, const VCN vcn, 
 * ntfs_attr_find_vcn_nolock - find a vcn in the runlist of an ntfs inode

 * @ni:		ntfs inode describing the runlist to search

 * @vcn:	vcn to find

 * @write_locked:	true if the runlist is locked for writing

 * @ctx:	active attribute search context if present or NULL if not

 *

 * Find the virtual cluster number @vcn in the runlist described by the ntfs

 * inode @ni and return the address of the runlist element containing the @vcn.
@@ -416,9 +416,22 @@ LCN ntfs_attr_vcn_to_lcn_nolock(ntfs_inode *ni, const VCN vcn, 
 * If the @vcn is not mapped yet, the attempt is made to map the attribute

 * extent containing the @vcn and the vcn to lcn conversion is retried.

 *

 * If @write_locked is true the caller has locked the runlist for writing and

 * if false for reading.

 * If @ctx is specified, it is an active search context of @ni and its base mft

 * record.  This is needed when ntfs_attr_find_vcn_nolock() 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_attr_find_vcn_nolock()

 * will perform the necessary mapping and unmapping.

 *

 * Note, ntfs_attr_find_vcn_nolock() 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_attr_find_vcn_nolock(), 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 you need to distinguish between the lcn of the returned runlist element

 * being >= 0 and LCN_HOLE.  In the later case you have to return zeroes on

 * read and allocate clusters on write.
@@ -433,22 +446,31 @@ LCN ntfs_attr_vcn_to_lcn_nolock(ntfs_inode *ni, const VCN vcn, 
 *	-ENOMEM - Not enough memory to map runlist.

 *	-EIO	- Critical error (runlist/file is corrupt, i/o error, etc).

 *

 * Locking: - The runlist must be locked on entry and is left locked on return.

 *	    - If @write_locked is FALSE, i.e. the runlist is locked for reading,

 *	      the lock may be dropped inside the function so you cannot rely on

 *	      the runlist still being the same when this function returns.

 * 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.

 *	    - 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.

 */

runlist_element *ntfs_attr_find_vcn_nolock(ntfs_inode *ni, const VCN vcn,

		const BOOL write_locked)

		ntfs_attr_search_ctx *ctx)

{

	unsigned long flags;

	runlist_element *rl;

	int err = 0;

	BOOL is_retry = FALSE;



	ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, %s_locked.",

			ni->mft_no, (unsigned long long)vcn,

			write_locked ? "write" : "read");

	ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, with%s ctx.",

			ni->mft_no, (unsigned long long)vcn, ctx ? "" : "out");

	BUG_ON(!ni);

	BUG_ON(!NInoNonResident(ni));

	BUG_ON(vcn < 0);
@@ -482,33 +504,22 @@ runlist_element *ntfs_attr_find_vcn_nolock(ntfs_inode *ni, const VCN vcn, 
	}

	if (!err && !is_retry) {

		/*

		 * The @vcn is in an unmapped region, map the runlist and

		 * retry.

		 * If the search context is invalid we cannot map the unmapped

		 * region.

		 */

		if (!write_locked) {

			up_read(&ni->runlist.lock);

			down_write(&ni->runlist.lock);

			if (unlikely(ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn) !=

					LCN_RL_NOT_MAPPED)) {

				up_write(&ni->runlist.lock);

				down_read(&ni->runlist.lock);

				goto retry_remap;

			}

		}

		err = ntfs_map_runlist_nolock(ni, vcn, NULL);

		if (!write_locked) {

			up_write(&ni->runlist.lock);

			down_read(&ni->runlist.lock);

		}

		if (IS_ERR(ctx->mrec))

			err = PTR_ERR(ctx->mrec);

		else {

			/*

			 * The @vcn is in an unmapped region, map the runlist

			 * and retry.

			 */

			err = ntfs_map_runlist_nolock(ni, vcn, ctx);

			if (likely(!err)) {

				is_retry = TRUE;

				goto retry_remap;

			}

		/*

		 * -EINVAL coming from a failed mapping attempt is equivalent

		 * to i/o error for us as it should not happen in our code

		 * paths.

		 */

		}

		if (err == -EINVAL)

			err = -EIO;

	} else if (!err)
@@ -1181,6 +1192,7 @@ int ntfs_attr_lookup(const ATTR_TYPE type, const ntfschar *name, 
	ntfs_inode *base_ni;



	ntfs_debug("Entering.");

	BUG_ON(IS_ERR(ctx->mrec));

	if (ctx->base_ntfs_ino)

		base_ni = ctx->base_ntfs_ino;

	else

fs/ntfs/attrib.h

+1 −1
Original line number Diff line number Diff line
@@ -68,7 +68,7 @@ extern LCN ntfs_attr_vcn_to_lcn_nolock(ntfs_inode *ni, const VCN vcn, 
		const BOOL write_locked);



extern runlist_element *ntfs_attr_find_vcn_nolock(ntfs_inode *ni,

		const VCN vcn, const BOOL write_locked);

		const VCN vcn, ntfs_attr_search_ctx *ctx);



int ntfs_attr_lookup(const ATTR_TYPE type, const ntfschar *name,

		const u32 name_len, const IGNORE_CASE_BOOL ic,

fs/ntfs/lcnalloc.c

+2 −2
Original line number Diff line number Diff line
@@ -839,7 +839,7 @@ s64 __ntfs_cluster_free(ntfs_inode *ni, const VCN start_vcn, s64 count, 


	total_freed = real_freed = 0;



	rl = ntfs_attr_find_vcn_nolock(ni, start_vcn, TRUE);

	rl = ntfs_attr_find_vcn_nolock(ni, start_vcn, NULL);

	if (IS_ERR(rl)) {

		if (!is_rollback)

			ntfs_error(vol->sb, "Failed to find first runlist "
@@ -893,7 +893,7 @@ s64 __ntfs_cluster_free(ntfs_inode *ni, const VCN start_vcn, s64 count, 


			/* Attempt to map runlist. */

			vcn = rl->vcn;

			rl = ntfs_attr_find_vcn_nolock(ni, vcn, TRUE);

			rl = ntfs_attr_find_vcn_nolock(ni, vcn, NULL);

			if (IS_ERR(rl)) {

				err = PTR_ERR(rl);

				if (!is_rollback)

fs/ntfs/mft.c

+4 −3
Original line number Diff line number Diff line
@@ -49,7 +49,8 @@ static inline MFT_RECORD *map_mft_record_page(ntfs_inode *ni) 
	ntfs_volume *vol = ni->vol;

	struct inode *mft_vi = vol->mft_ino;

	struct page *page;

	unsigned long index, ofs, end_index;

	unsigned long index, end_index;

	unsigned ofs;



	BUG_ON(ni->page);

	/*
@@ -1308,7 +1309,7 @@ static int ntfs_mft_bitmap_extend_allocation_nolock(ntfs_volume *vol) 
	ll = mftbmp_ni->allocated_size;

	read_unlock_irqrestore(&mftbmp_ni->size_lock, flags);

	rl = ntfs_attr_find_vcn_nolock(mftbmp_ni,

			(ll - 1) >> vol->cluster_size_bits, TRUE);

			(ll - 1) >> vol->cluster_size_bits, NULL);

	if (unlikely(IS_ERR(rl) || !rl->length || rl->lcn < 0)) {

		up_write(&mftbmp_ni->runlist.lock);

		ntfs_error(vol->sb, "Failed to determine last allocated "
@@ -1738,7 +1739,7 @@ static int ntfs_mft_data_extend_allocation_nolock(ntfs_volume *vol) 
	ll = mft_ni->allocated_size;

	read_unlock_irqrestore(&mft_ni->size_lock, flags);

	rl = ntfs_attr_find_vcn_nolock(mft_ni,

			(ll - 1) >> vol->cluster_size_bits, TRUE);

			(ll - 1) >> vol->cluster_size_bits, NULL);

	if (unlikely(IS_ERR(rl) || !rl->length || rl->lcn < 0)) {

		up_write(&mft_ni->runlist.lock);

		ntfs_error(vol->sb, "Failed to determine last allocated "