lcnalloc.c

linux 内核源代码

							"0x%llx.",
							(unsigned long long)
							(lcn + bmp_pos));
				rl2 = ntfs_malloc_nofs(rlsize + (int)PAGE_SIZE);
				if (unlikely(!rl2)) {
					err = -ENOMEM;
					ntfs_error(vol->sb, "Failed to "
							"allocate memory.");
					goto out;
				}
				memcpy(rl2, rl, rlsize);
				ntfs_free(rl);
				rl = rl2;
				rlsize += PAGE_SIZE;
				ntfs_debug("Reallocated memory, rlsize 0x%x.",
						rlsize);
			}
			/* Allocate the bitmap bit. */
			*byte |= bit;
			/* We need to write this bitmap page to disk. */
			need_writeback = 1;
			ntfs_debug("*byte 0x%x, need_writeback is set.",
					(unsigned int)*byte);
			/*
			 * Coalesce with previous run if adjacent LCNs.
			 * Otherwise, append a new run.
			 */
			ntfs_debug("Adding run (lcn 0x%llx, len 0x%llx), "
					"prev_lcn 0x%llx, lcn 0x%llx, "
					"bmp_pos 0x%llx, prev_run_len 0x%llx, "
					"rlpos %i.",
					(unsigned long long)(lcn + bmp_pos),
					1ULL, (unsigned long long)prev_lcn,
					(unsigned long long)lcn,
					(unsigned long long)bmp_pos,
					(unsigned long long)prev_run_len,
					rlpos);
			if (prev_lcn == lcn + bmp_pos - prev_run_len && rlpos) {
				ntfs_debug("Coalescing to run (lcn 0x%llx, "
						"len 0x%llx).",
						(unsigned long long)
						rl[rlpos - 1].lcn,
						(unsigned long long)
						rl[rlpos - 1].length);
				rl[rlpos - 1].length = ++prev_run_len;
				ntfs_debug("Run now (lcn 0x%llx, len 0x%llx), "
						"prev_run_len 0x%llx.",
						(unsigned long long)
						rl[rlpos - 1].lcn,
						(unsigned long long)
						rl[rlpos - 1].length,
						(unsigned long long)
						prev_run_len);
			} else {
				if (likely(rlpos)) {
					ntfs_debug("Adding new run, (previous "
							"run lcn 0x%llx, "
							"len 0x%llx).",
							(unsigned long long)
							rl[rlpos - 1].lcn,
							(unsigned long long)
							rl[rlpos - 1].length);
					rl[rlpos].vcn = rl[rlpos - 1].vcn +
							prev_run_len;
				} else {
					ntfs_debug("Adding new run, is first "
							"run.");
					rl[rlpos].vcn = start_vcn;
				}
				rl[rlpos].lcn = prev_lcn = lcn + bmp_pos;
				rl[rlpos].length = prev_run_len = 1;
				rlpos++;
			}
			/* Done? */
			if (!--clusters) {
				LCN tc;
				/*
				 * Update the current zone position.  Positions
				 * of already scanned zones have been updated
				 * during the respective zone switches.
				 */
				tc = lcn + bmp_pos + 1;
				ntfs_debug("Done. Updating current zone "
						"position, tc 0x%llx, "
						"search_zone %i.",
						(unsigned long long)tc,
						search_zone);
				switch (search_zone) {
				case 1:
					ntfs_debug("Before checks, "
							"vol->mft_zone_pos "
							"0x%llx.",
							(unsigned long long)
							vol->mft_zone_pos);
					if (tc >= vol->mft_zone_end) {
						vol->mft_zone_pos =
								vol->mft_lcn;
						if (!vol->mft_zone_end)
							vol->mft_zone_pos = 0;
					} else if ((bmp_initial_pos >=
							vol->mft_zone_pos ||
							tc > vol->mft_zone_pos)
							&& tc >= vol->mft_lcn)
						vol->mft_zone_pos = tc;
					ntfs_debug("After checks, "
							"vol->mft_zone_pos "
							"0x%llx.",
							(unsigned long long)
							vol->mft_zone_pos);
					break;
				case 2:
					ntfs_debug("Before checks, "
							"vol->data1_zone_pos "
							"0x%llx.",
							(unsigned long long)
							vol->data1_zone_pos);
					if (tc >= vol->nr_clusters)
						vol->data1_zone_pos =
							     vol->mft_zone_end;
					else if ((bmp_initial_pos >=
						    vol->data1_zone_pos ||
						    tc > vol->data1_zone_pos)
						    && tc >= vol->mft_zone_end)
						vol->data1_zone_pos = tc;
					ntfs_debug("After checks, "
							"vol->data1_zone_pos "
							"0x%llx.",
							(unsigned long long)
							vol->data1_zone_pos);
					break;
				case 4:
					ntfs_debug("Before checks, "
							"vol->data2_zone_pos "
							"0x%llx.",
							(unsigned long long)
							vol->data2_zone_pos);
					if (tc >= vol->mft_zone_start)
						vol->data2_zone_pos = 0;
					else if (bmp_initial_pos >=
						      vol->data2_zone_pos ||
						      tc > vol->data2_zone_pos)
						vol->data2_zone_pos = tc;
					ntfs_debug("After checks, "
							"vol->data2_zone_pos "
							"0x%llx.",
							(unsigned long long)
							vol->data2_zone_pos);
					break;
				default:
					BUG();
				}
				ntfs_debug("Finished.  Going to out.");
				goto out;
			}
			lcn++;
		}
		bmp_pos += buf_size;
		ntfs_debug("After inner while loop: buf_size 0x%x, lcn "
				"0x%llx, bmp_pos 0x%llx, need_writeback %i.",
				buf_size, (unsigned long long)lcn,
				(unsigned long long)bmp_pos, need_writeback);
		if (bmp_pos < zone_end) {
			ntfs_debug("Continuing outer while loop, "
					"bmp_pos 0x%llx, zone_end 0x%llx.",
					(unsigned long long)bmp_pos,
					(unsigned long long)zone_end);
			continue;
		}
zone_pass_done:	/* Finished with the current zone pass. */
		ntfs_debug("At zone_pass_done, pass %i.", pass);
		if (pass == 1) {
			/*
			 * Now do pass 2, scanning the first part of the zone
			 * we omitted in pass 1.
			 */
			pass = 2;
			zone_end = zone_start;
			switch (search_zone) {
			case 1: /* mft_zone */
				zone_start = vol->mft_zone_start;
				break;
			case 2: /* data1_zone */
				zone_start = vol->mft_zone_end;
				break;
			case 4: /* data2_zone */
				zone_start = 0;
				break;
			default:
				BUG();
			}
			/* Sanity check. */
			if (zone_end < zone_start)
				zone_end = zone_start;
			bmp_pos = zone_start;
			ntfs_debug("Continuing outer while loop, pass 2, "
					"zone_start 0x%llx, zone_end 0x%llx, "
					"bmp_pos 0x%llx.",
					(unsigned long long)zone_start,
					(unsigned long long)zone_end,
					(unsigned long long)bmp_pos);
			continue;
		} /* pass == 2 */
done_zones_check:
		ntfs_debug("At done_zones_check, search_zone %i, done_zones "
				"before 0x%x, done_zones after 0x%x.",
				search_zone, done_zones,
				done_zones | search_zone);
		done_zones |= search_zone;
		if (done_zones < 7) {
			ntfs_debug("Switching zone.");
			/* Now switch to the next zone we haven't done yet. */
			pass = 1;
			switch (search_zone) {
			case 1:
				ntfs_debug("Switching from mft zone to data1 "
						"zone.");
				/* Update mft zone position. */
				if (rlpos) {
					LCN tc;

					ntfs_debug("Before checks, "
							"vol->mft_zone_pos "
							"0x%llx.",
							(unsigned long long)
							vol->mft_zone_pos);
					tc = rl[rlpos - 1].lcn +
							rl[rlpos - 1].length;
					if (tc >= vol->mft_zone_end) {
						vol->mft_zone_pos =
								vol->mft_lcn;
						if (!vol->mft_zone_end)
							vol->mft_zone_pos = 0;
					} else if ((bmp_initial_pos >=
							vol->mft_zone_pos ||
							tc > vol->mft_zone_pos)
							&& tc >= vol->mft_lcn)
						vol->mft_zone_pos = tc;
					ntfs_debug("After checks, "
							"vol->mft_zone_pos "
							"0x%llx.",
							(unsigned long long)
							vol->mft_zone_pos);
				}
				/* Switch from mft zone to data1 zone. */
switch_to_data1_zone:		search_zone = 2;
				zone_start = bmp_initial_pos =
						vol->data1_zone_pos;
				zone_end = vol->nr_clusters;
				if (zone_start == vol->mft_zone_end)
					pass = 2;
				if (zone_start >= zone_end) {
					vol->data1_zone_pos = zone_start =
							vol->mft_zone_end;
					pass = 2;
				}
				break;
			case 2:
				ntfs_debug("Switching from data1 zone to "
						"data2 zone.");
				/* Update data1 zone position. */
				if (rlpos) {
					LCN tc;

					ntfs_debug("Before checks, "
							"vol->data1_zone_pos "
							"0x%llx.",
							(unsigned long long)
							vol->data1_zone_pos);
					tc = rl[rlpos - 1].lcn +
							rl[rlpos - 1].length;
					if (tc >= vol->nr_clusters)
						vol->data1_zone_pos =
							     vol->mft_zone_end;
					else if ((bmp_initial_pos >=
						    vol->data1_zone_pos ||
						    tc > vol->data1_zone_pos)
						    && tc >= vol->mft_zone_end)
						vol->data1_zone_pos = tc;
					ntfs_debug("After checks, "
							"vol->data1_zone_pos "
							"0x%llx.",
							(unsigned long long)
							vol->data1_zone_pos);
				}
				/* Switch from data1 zone to data2 zone. */
				search_zone = 4;
				zone_start = bmp_initial_pos =
						vol->data2_zone_pos;
				zone_end = vol->mft_zone_start;
				if (!zone_start)
					pass = 2;
				if (zone_start >= zone_end) {
					vol->data2_zone_pos = zone_start =
							bmp_initial_pos = 0;
					pass = 2;
				}
				break;
			case 4:
				ntfs_debug("Switching from data2 zone to "
						"data1 zone.");
				/* Update data2 zone position. */
				if (rlpos) {
					LCN tc;

					ntfs_debug("Before checks, "
							"vol->data2_zone_pos "
							"0x%llx.",
							(unsigned long long)
							vol->data2_zone_pos);
					tc = rl[rlpos - 1].lcn +
							rl[rlpos - 1].length;
					if (tc >= vol->mft_zone_start)
						vol->data2_zone_pos = 0;
					else if (bmp_initial_pos >=
						      vol->data2_zone_pos ||
						      tc > vol->data2_zone_pos)
						vol->data2_zone_pos = tc;
					ntfs_debug("After checks, "
							"vol->data2_zone_pos "
							"0x%llx.",
							(unsigned long long)
							vol->data2_zone_pos);
				}
				/* Switch from data2 zone to data1 zone. */
				goto switch_to_data1_zone;
			default:
				BUG();
			}
			ntfs_debug("After zone switch, search_zone %i, "
					"pass %i, bmp_initial_pos 0x%llx, "
					"zone_start 0x%llx, zone_end 0x%llx.",
					search_zone, pass,
					(unsigned long long)bmp_initial_pos,
					(unsigned long long)zone_start,
					(unsigned long long)zone_end);
			bmp_pos = zone_start;
			if (zone_start == zone_end) {
				ntfs_debug("Empty zone, going to "
						"done_zones_check.");