Make libntfs keep track number of free clusters and MFT records.

Thanks for idea to David Fox and Szabolcs Szakacsits.

include/ntfs/volume.h

@@ -208,10 +208,8 @@ struct _ntfs_volume {
 	s32 attrdef_len;	/* Size of the attribute definition table in
 				   bytes. */
 
-	/* Temp: for directory handling */
-	void *private_data;	/* ntfs_dir for . */
-	void *private_bmp1;	/* ntfs_bmp for $MFT/$BITMAP */
-	void *private_bmp2;	/* ntfs_bmp for $Bitmap */
+	long nr_free_clusters;	/* This two are self explaining. */
+	long nr_free_mft_records;
 };
 
 extern ntfs_volume *ntfs_volume_alloc(void);

libntfs/bitmap.c

@@ -58,7 +58,8 @@
 static int ntfs_bitmap_set_bits_in_run(ntfs_attr *na, s64 start_bit,
 		s64 count, int value)
 {
-	s64 bufsize, br;
+	ntfs_volume *vol = na->ni->vol;
+	s64 bufsize, br, left = count;
 	u8 *buf, *lastbyte_buf;
 	int bit, firstbyte, lastbyte, lastbyte_pos, tmp, err;
 
@@ -95,7 +96,7 @@ static int ntfs_bitmap_set_bits_in_run(ntfs_attr *na, s64 start_bit,
 			return -1;
 		}
 		/* and set or clear the appropriate bits in it. */
-		while ((bit & 7) && count--) {
+		while ((bit & 7) && left--) {
 			if (value)
 				*buf |= 1 << bit++;
 			else
@@ -105,14 +106,14 @@ static int ntfs_bitmap_set_bits_in_run(ntfs_attr *na, s64 start_bit,
 		start_bit = (start_bit + 7) & ~7;
 	}
 
-	/* Loop until @count reaches zero. */
+	/* Loop until @left reaches zero. */
 	lastbyte = 0;
 	lastbyte_buf = NULL;
-	bit = count & 7;
+	bit = left & 7;
 	do {
 		/* If there is a last partial byte... */
-		if (count > 0 && bit) {
-			lastbyte_pos = ((count + 7) >> 3) + firstbyte;
+		if (left > 0 && bit) {
+			lastbyte_pos = ((left + 7) >> 3) + firstbyte;
 			if (!lastbyte_pos) {
 				// FIXME: Eeek! BUG!
 				ntfs_log_trace("lastbyte is zero. Leaving "
@@ -125,7 +126,7 @@ static int ntfs_bitmap_set_bits_in_run(ntfs_attr *na, s64 start_bit,
 				lastbyte_buf = buf + lastbyte_pos - 1;
 
 				/* read the byte in... */
-				br = ntfs_attr_pread(na, (start_bit + count) >>
+				br = ntfs_attr_pread(na, (start_bit + left) >>
 						3, 1, lastbyte_buf);
 				if (br != 1) {
 					// FIXME: Eeek! We need rollback! (AIA)
@@ -137,7 +138,7 @@ static int ntfs_bitmap_set_bits_in_run(ntfs_attr *na, s64 start_bit,
 					goto free_err_out;
 				}
 				/* and set/clear the appropriate bits in it. */
-				while (bit && count--) {
+				while (bit && left--) {
 					if (value)
 						*lastbyte_buf |= 1 << --bit;
 					else
@@ -172,19 +173,33 @@ static int ntfs_bitmap_set_bits_in_run(ntfs_attr *na, s64 start_bit,
 			*buf = value ? 0xff : 0;
 		}
 		start_bit += tmp;
-		count -= tmp;
-		if (bufsize > (tmp = (count + 7) >> 3))
+		left -= tmp;
+		if (bufsize > (tmp = (left + 7) >> 3))
 			bufsize = tmp;
 
-		if (lastbyte && count != 0) {
+		if (lastbyte && left != 0) {
 			// FIXME: Eeek! BUG!
 			ntfs_log_trace("Last buffer but count is not zero (= "
 					"%lli). Leaving inconsistent metadata."
-					"\n", (long long)count);
+					"\n", (long long)left);
 			err = EIO;
 			goto free_err_out;
 		}
-	} while (count > 0);
+	} while (left > 0);
+
+	/* Update free clusters and MFT records. */
+	if (na == vol->mftbmp_na) {
+		if (value)
+			vol->nr_free_mft_records -= count;
+		else
+			vol->nr_free_mft_records += count;
+	}
+	if (na == vol->lcnbmp_na) {
+		if (value)
+			vol->nr_free_clusters -= count;
+		else
+			vol->nr_free_clusters += count;
+	}
 
 	/* Done! */
 	free(buf);

libntfs/lcnalloc.c

@@ -287,6 +287,7 @@ runlist *ntfs_cluster_alloc(ntfs_volume *vol, VCN start_vcn, s64 count,
 			}
 			/* Allocate the bitmap bit. */
 			*byte |= bit;
+			vol->nr_free_clusters--;
 			/* We need to write this bitmap buffer back to disk! */
 			need_writeback = 1;
 			ntfs_log_trace("*byte = 0x%x, need_writeback is set.\n",

libntfs/mft.c

@@ -609,6 +609,7 @@ static int ntfs_mft_bitmap_extend_allocation(ntfs_volume *vol)
 				errno = EIO;
 			return -1;
 		}
+		vol->nr_free_clusters--;
 		/* Update the mft bitmap runlist. */
 		rl->length++;
 		rl[1].vcn++;
@@ -833,6 +834,7 @@ static int ntfs_mft_bitmap_extend_initialized(ntfs_volume *vol)
 		ntfs_log_debug("Wrote eight initialized bytes to mft bitmap.\n");
 		return 0;
 	}
+	vol->nr_free_mft_records += 64; /* 8 bytes x 8 bits each. */
 	ntfs_log_error("Failed to write to mft bitmap.\n");
 	err = errno;
 	if (ll >= 0)

libntfs/volume.c

@@ -744,6 +744,88 @@ out:
 	return ret;
 }
 
+/**
+ * ntfs_volume_get_nr_free_mft_records - calculate number of free MFT records
+ * vol:		ntfs volume for which perform calculations.
+ *
+ * This function initializes @vol->nr_free_mft_records. @vol->mftbmp_na should
+ * be already opened upon call to this function.
+ *
+ * Return 0 on success. On error return -1 with errno set appropriately and
+ * @vol->nr_free_mft_records is not touched in this case.
+ */
+static int ntfs_volume_get_nr_free_mft_records(ntfs_volume *vol)
+{
+	long nr_free = vol->mft_na->data_size >> vol->mft_record_size_bits;
+	s64 br, total = 0;
+	u8 *buf;
+
+	buf = ntfs_malloc(vol->cluster_size);
+	if (!buf)
+		return -1;
+	while (1) {
+		int i, j;
+
+		br = ntfs_attr_pread(vol->mftbmp_na, total,
+				vol->cluster_size, buf);
+		if (br <= 0)
+			break;
+		total += br;
+		for (i = 0; i < br; i++)
+			for (j = 0; j < 8; j++)
+				if ((buf[i] >> j) & 1)
+					nr_free--;
+	}
+	free(buf);
+	if (!total || br < 0) {
+		ntfs_log_error("pread: %s\n", strerror(errno));
+		return -1;
+	}
+	vol->nr_free_mft_records = nr_free;
+	return 0;
+}
+
+/**
+ * ntfs_volume_get_nr_free_clusters - calculate number of free clusters
+ * vol:		ntfs volume for which perform calculations.
+ *
+ * This function initializes @vol->nr_free_clusters. @vol->lcnbmp_na should be
+ * already opened upon call to this function.
+ *
+ * Return 0 on success. On error return -1 with errno set appropriately and
+ * @vol->nr_free_clusters is not touched in this case.
+ */
+static long ntfs_volume_get_nr_free_clusters(ntfs_volume *vol)
+{
+	long nr_free = vol->nr_clusters;
+	s64 br, total = 0;
+	u8 *buf;
+
+	buf = ntfs_malloc(vol->cluster_size);
+	if (!buf)
+		return -1;
+	while (1) {
+		int i, j;
+
+		br = ntfs_attr_pread(vol->lcnbmp_na, total,
+				vol->cluster_size, buf);
+		if (br <= 0)
+			break;
+		total += br;
+		for (i = 0; i < br; i++)
+			for (j = 0; j < 8; j++)
+				if ((buf[i] >> j) & 1)
+					nr_free--;
+	}
+	free(buf);
+	if (!total || br < 0) {
+		ntfs_log_error("pread: %s\n", strerror(errno));
+		return -1;
+	}
+	vol->nr_free_clusters = nr_free;
+	return 0;
+}
+
 /**
  * ntfs_device_mount - open ntfs volume
  * @dev:	device to open
@@ -1127,6 +1209,15 @@ ntfs_volume *ntfs_device_mount(struct ntfs_device *dev, ntfs_mount_flags flags)
 	ntfs_attr_close(na);
 	if (ntfs_inode_close(ni))
 		ntfs_log_perror("Failed to close inode, leaking memory");
+	/* Initialize number of free clusters and MFT records. */
+	if (ntfs_volume_get_nr_free_mft_records(vol)) {
+		ntfs_log_perror("Failed to calculate number of free MFTs");
+		goto error_exit;
+	}
+	if (ntfs_volume_get_nr_free_clusters(vol)) {
+		ntfs_log_perror("Failed to calculate number of free clusters");
+		goto error_exit;
+	}
 	/*
 	 * Check for dirty logfile and hibernated Windows.
 	 * We care only about read-write mounts.

ntfsprogs/ntfsmount.c

@@ -97,9 +97,6 @@ typedef struct {
 	char *mnt_point;
 	char *device;
 	char *locale;
-	int state;
-	long free_clusters;
-	long free_mft;
 	unsigned int uid;
 	unsigned int gid;
 	unsigned int fmask;
@@ -119,13 +116,6 @@ typedef struct {
 	BOOL blkdev;
 } ntfs_fuse_context_t;
 
-typedef enum {
-	NF_FreeClustersOutdate	= (1 << 0),  /* Information about amount of
-						free clusters is outdated. */
-	NF_FreeMFTOutdate	= (1 << 1),  /* Information about amount of
-						free MFT records is outdated. */
-} ntfs_fuse_state_bits;
-
 #define NTFS_FUSE_OPT(t, p) { t, offsetof(ntfs_fuse_context_t, p), TRUE }
 #define NTFS_FUSE_OPT_NEG(t, p) { t, offsetof(ntfs_fuse_context_t, p), FALSE }
 #define NTFS_FUSE_OPT_VAL(t, p, v) { t, offsetof(ntfs_fuse_context_t, p), v }
@@ -187,15 +177,6 @@ static char ntfs_fuse_default_options[] =
 		"default_permissions,allow_other,use_ino,kernel_cache,nonempty";
 static ntfs_fuse_context_t *ctx;
 
-/**
- * ntfs_fuse_mark_free_space_outdated - forces free space recalculation
- */
-static __inline__ void ntfs_fuse_mark_free_space_outdated(void)
-{
-	/* Mark information about free MFT record and clusters outdated. */
-	ctx->state |= (NF_FreeClustersOutdate | NF_FreeMFTOutdate);
-}
-
 /**
  * ntfs_fuse_is_named_data_stream - check path to be to named data stream
  * @path:	path to check
@@ -221,73 +202,6 @@ static __inline__ void ntfs_fuse_update_times(ntfs_inode *ni,
 	ntfs_inode_update_times(ni, mask);
 }
 
-static long ntfs_fuse_get_nr_free_mft_records(ntfs_volume *vol, long nr_free)
-{
-	u8 *buf;
-	s64 br, total = 0;
-
-	if (!(ctx->state & NF_FreeMFTOutdate))
-		return ctx->free_mft;
-	buf = ntfs_malloc(vol->cluster_size);
-	if (!buf)
-		return -errno;
-	while (1) {
-		int i, j;
-
-		br = ntfs_attr_pread(vol->mftbmp_na, total,
-				vol->cluster_size, buf);
-		if (br <= 0)
-			break;
-		total += br;
-		for (i = 0; i < br; i++)
-			for (j = 0; j < 8; j++)
-				if ((buf[i] >> j) & 1)
-					nr_free--;
-	}
-	free(buf);
-	if (!total || br < 0) {
-		ntfs_log_error("pread: %s\n", strerror(errno));
-		return -errno;
-	}
-	ctx->free_mft = nr_free;
-	ctx->state &= ~(NF_FreeMFTOutdate);
-	return nr_free;
-}
-
-static long ntfs_fuse_get_nr_free_clusters(ntfs_volume *vol)
-{
-	u8 *buf;
-	long nr_free = vol->nr_clusters;
-	s64 br, total = 0;
-
-	if (!(ctx->state & NF_FreeClustersOutdate))
-		return ctx->free_clusters;
-	buf = ntfs_malloc(vol->cluster_size);
-	if (!buf)
-		return -errno;
-	while (1) {
-		int i, j;
-
-		br = ntfs_attr_pread(vol->lcnbmp_na, total,
-				vol->cluster_size, buf);
-		if (br <= 0)
-			break;
-		total += br;
-		for (i = 0; i < br; i++)
-			for (j = 0; j < 8; j++)
-				if ((buf[i] >> j) & 1)
-					nr_free--;
-	}
-	free(buf);
-	if (!total || br < 0) {
-		ntfs_log_error("pread: %s\n", strerror(errno));
-		return -errno;
-	}
-	ctx->free_clusters = nr_free;
-	ctx->state &= ~(NF_FreeClustersOutdate);
-	return nr_free;
-}
-
 /**
  * ntfs_fuse_statfs - return information about mounted NTFS volume
  * @path:	ignored (but fuse requires it)
@@ -308,8 +222,6 @@ static long ntfs_fuse_get_nr_free_clusters(ntfs_volume *vol)
 static int ntfs_fuse_statfs(const char *path __attribute__((unused)),
 		struct statvfs *sfs)
 {
-	long size;
-
 	/* Optimal transfer block size. */
 	sfs->f_bsize = ctx->vol->cluster_size;
 	sfs->f_frsize = ctx->vol->cluster_size;
@@ -319,20 +231,16 @@ static int ntfs_fuse_statfs(const char *path __attribute__((unused)),
 	 * the total clusters.
 	 */
 	sfs->f_blocks = ctx->vol->nr_clusters;
-	/* Free data blocks in file system in units of f_bsize. */
-	size = ntfs_fuse_get_nr_free_clusters(ctx->vol);
-	if (size < 0)
-		size = 0;
-	/* Free blocks avail to non-superuser, same as above on NTFS. */
-	sfs->f_bavail = sfs->f_bfree = size;
+	/*
+	 * Free data blocks and free data block available to non-superuser in
+	 * file system in units of f_bsize.
+	 */
+	sfs->f_bavail = sfs->f_bfree = ctx->vol->nr_free_clusters;
 	/* Number of inodes in file system (at this point in time). */
-	size = ctx->vol->mft_na->data_size >> ctx->vol->mft_record_size_bits;
-	sfs->f_files = size; 
+	sfs->f_files = ctx->vol->mft_na->data_size >>
+			ctx->vol->mft_record_size_bits;
 	/* Free inodes in fs (based on current total count). */
-	size = ntfs_fuse_get_nr_free_mft_records(ctx->vol, size);
-	if (size < 0)
-		size = 0;
-	sfs->f_ffree = size;
+	sfs->f_ffree = ctx->vol->nr_free_mft_records;
 	/* Maximum length of filenames. */
 	sfs->f_namemax = NTFS_MAX_NAME_LEN;
 	return 0;
@@ -746,7 +654,6 @@ static int ntfs_fuse_write(const char *org_path, const char *buf, size_t size,
 	}
 	res = total;
 exit:
-	ntfs_fuse_mark_free_space_outdated();
 	if (res > 0)
 		ntfs_fuse_update_times(ni, NTFS_UPDATE_MTIME |
 				NTFS_UPDATE_CTIME);
@@ -793,7 +700,6 @@ static int ntfs_fuse_truncate(const char *org_path, off_t size)
 				NTFS_UPDATE_CTIME);
 		res = 0;
 	}
-	ntfs_fuse_mark_free_space_outdated();
 	ntfs_attr_close(na);
 exit:
 	if (ni && ntfs_inode_close(ni))
@@ -938,7 +844,6 @@ static int ntfs_fuse_mknod(const char *org_path, mode_t mode, dev_t dev)
 	else
 		res = ntfs_fuse_create_stream(path, stream_name,
 				stream_name_len);
-	ntfs_fuse_mark_free_space_outdated();
 exit:
 	free(path);
 	if (stream_name_len)
@@ -950,7 +855,6 @@ static int ntfs_fuse_symlink(const char *to, const char *from)
 {
 	if (ntfs_fuse_is_named_data_stream(from))
 		return -EINVAL; /* n/a for named data streams. */
-	ntfs_fuse_mark_free_space_outdated();
 	return ntfs_fuse_create(from, S_IFLNK, 0, to);
 }
 
@@ -992,7 +896,6 @@ static int ntfs_fuse_link(const char *old_path, const char *new_path)
 			res = -EIO;
 		goto exit;
 	}
-	ntfs_fuse_mark_free_space_outdated();
 	/* Create hard link. */
 	if (ntfs_link(ni, dir_ni, uname, uname_len))
 		res = -errno;
@@ -1101,7 +1004,6 @@ static int ntfs_fuse_unlink(const char *org_path)
 		res = ntfs_fuse_rm(path);
 	else
 		res = ntfs_fuse_rm_stream(path, stream_name, stream_name_len);
-	ntfs_fuse_mark_free_space_outdated();
 	free(path);
 	if (stream_name_len)
 		free(stream_name);
@@ -1153,7 +1055,6 @@ static int ntfs_fuse_mkdir(const char *path,
 {
 	if (ntfs_fuse_is_named_data_stream(path))
 		return -EINVAL; /* n/a for named data streams. */
-	ntfs_fuse_mark_free_space_outdated();
 	return ntfs_fuse_create(path, S_IFDIR, 0, NULL);
 }
 
@@ -1161,7 +1062,6 @@ static int ntfs_fuse_rmdir(const char *path)
 {
 	if (ntfs_fuse_is_named_data_stream(path))
 		return -EINVAL; /* n/a for named data streams. */
-	ntfs_fuse_mark_free_space_outdated();
 	return ntfs_fuse_rm(path);
 }
 
@@ -1389,7 +1289,6 @@ static int ntfs_fuse_setxattr(const char *path, const char *name,
 		res = -EEXIST;
 		goto exit;
 	}
-	ntfs_fuse_mark_free_space_outdated();
 	if (!na) {
 		if (flags == XATTR_REPLACE) {
 			res = -ENODATA;
@@ -1444,7 +1343,6 @@ static int ntfs_fuse_removexattr(const char *path, const char *name)
 		res = -ENODATA;
 		goto exit;
 	}
-	ntfs_fuse_mark_free_space_outdated();
 	if (ntfs_attr_rm(na))
 		res = -errno;
 	na = NULL;
@@ -1543,7 +1441,6 @@ static int ntfs_fuse_init(void)
 		return -1;
 
 	*ctx = (ntfs_fuse_context_t) {
-		.state = NF_FreeClustersOutdate | NF_FreeMFTOutdate,
 		.uid = getuid(),
 		.gid = getgid(),
 		.fmask = 0111,