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-rw-r--r--fs/ntfs/lcnalloc.c1000
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diff --git a/fs/ntfs/lcnalloc.c b/fs/ntfs/lcnalloc.c
deleted file mode 100644
index eda9972e61..0000000000
--- a/fs/ntfs/lcnalloc.c
+++ /dev/null
@@ -1,1000 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * lcnalloc.c - Cluster (de)allocation code. Part of the Linux-NTFS project.
- *
- * Copyright (c) 2004-2005 Anton Altaparmakov
- */
-
-#ifdef NTFS_RW
-
-#include <linux/pagemap.h>
-
-#include "lcnalloc.h"
-#include "debug.h"
-#include "bitmap.h"
-#include "inode.h"
-#include "volume.h"
-#include "attrib.h"
-#include "malloc.h"
-#include "aops.h"
-#include "ntfs.h"
-
-/**
- * ntfs_cluster_free_from_rl_nolock - free clusters from runlist
- * @vol: mounted ntfs volume on which to free the clusters
- * @rl: runlist describing the clusters to free
- *
- * Free all the clusters described by the runlist @rl on the volume @vol. In
- * the case of an error being returned, at least some of the clusters were not
- * freed.
- *
- * Return 0 on success and -errno on error.
- *
- * Locking: - The volume lcn bitmap must be locked for writing on entry and is
- * left locked on return.
- */
-int ntfs_cluster_free_from_rl_nolock(ntfs_volume *vol,
- const runlist_element *rl)
-{
- struct inode *lcnbmp_vi = vol->lcnbmp_ino;
- int ret = 0;
-
- ntfs_debug("Entering.");
- if (!rl)
- return 0;
- for (; rl->length; rl++) {
- int err;
-
- if (rl->lcn < 0)
- continue;
- err = ntfs_bitmap_clear_run(lcnbmp_vi, rl->lcn, rl->length);
- if (unlikely(err && (!ret || ret == -ENOMEM) && ret != err))
- ret = err;
- }
- ntfs_debug("Done.");
- return ret;
-}
-
-/**
- * ntfs_cluster_alloc - allocate clusters on an ntfs volume
- * @vol: mounted ntfs volume on which to allocate the clusters
- * @start_vcn: vcn to use for the first allocated cluster
- * @count: number of clusters to allocate
- * @start_lcn: starting lcn at which to allocate the clusters (or -1 if none)
- * @zone: zone from which to allocate the clusters
- * @is_extension: if 'true', this is an attribute extension
- *
- * Allocate @count clusters preferably starting at cluster @start_lcn or at the
- * current allocator position if @start_lcn is -1, on the mounted ntfs volume
- * @vol. @zone is either DATA_ZONE for allocation of normal clusters or
- * MFT_ZONE for allocation of clusters for the master file table, i.e. the
- * $MFT/$DATA attribute.
- *
- * @start_vcn specifies the vcn of the first allocated cluster. This makes
- * merging the resulting runlist with the old runlist easier.
- *
- * If @is_extension is 'true', the caller is allocating clusters to extend an
- * attribute and if it is 'false', the caller is allocating clusters to fill a
- * hole in an attribute. Practically the difference is that if @is_extension
- * is 'true' the returned runlist will be terminated with LCN_ENOENT and if
- * @is_extension is 'false' the runlist will be terminated with
- * LCN_RL_NOT_MAPPED.
- *
- * You need to check the return value with IS_ERR(). If this is false, the
- * function was successful and the return value is a runlist describing the
- * allocated cluster(s). If IS_ERR() is true, the function failed and
- * PTR_ERR() gives you the error code.
- *
- * Notes on the allocation algorithm
- * =================================
- *
- * There are two data zones. First is the area between the end of the mft zone
- * and the end of the volume, and second is the area between the start of the
- * volume and the start of the mft zone. On unmodified/standard NTFS 1.x
- * volumes, the second data zone does not exist due to the mft zone being
- * expanded to cover the start of the volume in order to reserve space for the
- * mft bitmap attribute.
- *
- * This is not the prettiest function but the complexity stems from the need of
- * implementing the mft vs data zoned approach and from the fact that we have
- * access to the lcn bitmap in portions of up to 8192 bytes at a time, so we
- * need to cope with crossing over boundaries of two buffers. Further, the
- * fact that the allocator allows for caller supplied hints as to the location
- * of where allocation should begin and the fact that the allocator keeps track
- * of where in the data zones the next natural allocation should occur,
- * contribute to the complexity of the function. But it should all be
- * worthwhile, because this allocator should: 1) be a full implementation of
- * the MFT zone approach used by Windows NT, 2) cause reduction in
- * fragmentation, and 3) be speedy in allocations (the code is not optimized
- * for speed, but the algorithm is, so further speed improvements are probably
- * possible).
- *
- * FIXME: We should be monitoring cluster allocation and increment the MFT zone
- * size dynamically but this is something for the future. We will just cause
- * heavier fragmentation by not doing it and I am not even sure Windows would
- * grow the MFT zone dynamically, so it might even be correct not to do this.
- * The overhead in doing dynamic MFT zone expansion would be very large and
- * unlikely worth the effort. (AIA)
- *
- * TODO: I have added in double the required zone position pointer wrap around
- * logic which can be optimized to having only one of the two logic sets.
- * However, having the double logic will work fine, but if we have only one of
- * the sets and we get it wrong somewhere, then we get into trouble, so
- * removing the duplicate logic requires _very_ careful consideration of _all_
- * possible code paths. So at least for now, I am leaving the double logic -
- * better safe than sorry... (AIA)
- *
- * Locking: - 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.
- */
-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 bool is_extension)
-{
- LCN zone_start, zone_end, bmp_pos, bmp_initial_pos, last_read_pos, lcn;
- LCN prev_lcn = 0, prev_run_len = 0, mft_zone_size;
- s64 clusters;
- loff_t i_size;
- struct inode *lcnbmp_vi;
- runlist_element *rl = NULL;
- struct address_space *mapping;
- struct page *page = NULL;
- u8 *buf, *byte;
- int err = 0, rlpos, rlsize, buf_size;
- u8 pass, done_zones, search_zone, need_writeback = 0, bit;
-
- ntfs_debug("Entering for start_vcn 0x%llx, count 0x%llx, start_lcn "
- "0x%llx, zone %s_ZONE.", (unsigned long long)start_vcn,
- (unsigned long long)count,
- (unsigned long long)start_lcn,
- zone == MFT_ZONE ? "MFT" : "DATA");
- BUG_ON(!vol);
- lcnbmp_vi = vol->lcnbmp_ino;
- BUG_ON(!lcnbmp_vi);
- BUG_ON(start_vcn < 0);
- BUG_ON(count < 0);
- BUG_ON(start_lcn < -1);
- BUG_ON(zone < FIRST_ZONE);
- BUG_ON(zone > LAST_ZONE);
-
- /* Return NULL if @count is zero. */
- if (!count)
- return NULL;
- /* Take the lcnbmp lock for writing. */
- down_write(&vol->lcnbmp_lock);
- /*
- * If no specific @start_lcn was requested, use the current data zone
- * position, otherwise use the requested @start_lcn but make sure it
- * lies outside the mft zone. Also set done_zones to 0 (no zones done)
- * and pass depending on whether we are starting inside a zone (1) or
- * at the beginning of a zone (2). If requesting from the MFT_ZONE,
- * we either start at the current position within the mft zone or at
- * the specified position. If the latter is out of bounds then we start
- * at the beginning of the MFT_ZONE.
- */
- done_zones = 0;
- pass = 1;
- /*
- * zone_start and zone_end are the current search range. search_zone
- * is 1 for mft zone, 2 for data zone 1 (end of mft zone till end of
- * volume) and 4 for data zone 2 (start of volume till start of mft
- * zone).
- */
- zone_start = start_lcn;
- if (zone_start < 0) {
- if (zone == DATA_ZONE)
- zone_start = vol->data1_zone_pos;
- else
- zone_start = vol->mft_zone_pos;
- if (!zone_start) {
- /*
- * Zone starts at beginning of volume which means a
- * single pass is sufficient.
- */
- pass = 2;
- }
- } else if (zone == DATA_ZONE && zone_start >= vol->mft_zone_start &&
- zone_start < vol->mft_zone_end) {
- zone_start = vol->mft_zone_end;
- /*
- * Starting at beginning of data1_zone which means a single
- * pass in this zone is sufficient.
- */
- pass = 2;
- } else if (zone == MFT_ZONE && (zone_start < vol->mft_zone_start ||
- zone_start >= vol->mft_zone_end)) {
- zone_start = vol->mft_lcn;
- if (!vol->mft_zone_end)
- zone_start = 0;
- /*
- * Starting at beginning of volume which means a single pass
- * is sufficient.
- */
- pass = 2;
- }
- if (zone == MFT_ZONE) {
- zone_end = vol->mft_zone_end;
- search_zone = 1;
- } else /* if (zone == DATA_ZONE) */ {
- /* Skip searching the mft zone. */
- done_zones |= 1;
- if (zone_start >= vol->mft_zone_end) {
- zone_end = vol->nr_clusters;
- search_zone = 2;
- } else {
- zone_end = vol->mft_zone_start;
- search_zone = 4;
- }
- }
- /*
- * bmp_pos is the current bit position inside the bitmap. We use
- * bmp_initial_pos to determine whether or not to do a zone switch.
- */
- bmp_pos = bmp_initial_pos = zone_start;
-
- /* Loop until all clusters are allocated, i.e. clusters == 0. */
- clusters = count;
- rlpos = rlsize = 0;
- mapping = lcnbmp_vi->i_mapping;
- i_size = i_size_read(lcnbmp_vi);
- while (1) {
- ntfs_debug("Start of outer while loop: done_zones 0x%x, "
- "search_zone %i, pass %i, zone_start 0x%llx, "
- "zone_end 0x%llx, bmp_initial_pos 0x%llx, "
- "bmp_pos 0x%llx, rlpos %i, rlsize %i.",
- done_zones, search_zone, pass,
- (unsigned long long)zone_start,
- (unsigned long long)zone_end,
- (unsigned long long)bmp_initial_pos,
- (unsigned long long)bmp_pos, rlpos, rlsize);
- /* Loop until we run out of free clusters. */
- last_read_pos = bmp_pos >> 3;
- ntfs_debug("last_read_pos 0x%llx.",
- (unsigned long long)last_read_pos);
- if (last_read_pos > i_size) {
- ntfs_debug("End of attribute reached. "
- "Skipping to zone_pass_done.");
- goto zone_pass_done;
- }
- if (likely(page)) {
- if (need_writeback) {
- ntfs_debug("Marking page dirty.");
- flush_dcache_page(page);
- set_page_dirty(page);
- need_writeback = 0;
- }
- ntfs_unmap_page(page);
- }
- page = ntfs_map_page(mapping, last_read_pos >>
- PAGE_SHIFT);
- if (IS_ERR(page)) {
- err = PTR_ERR(page);
- ntfs_error(vol->sb, "Failed to map page.");
- goto out;
- }
- buf_size = last_read_pos & ~PAGE_MASK;
- buf = page_address(page) + buf_size;
- buf_size = PAGE_SIZE - buf_size;
- if (unlikely(last_read_pos + buf_size > i_size))
- buf_size = i_size - last_read_pos;
- buf_size <<= 3;
- lcn = bmp_pos & 7;
- bmp_pos &= ~(LCN)7;
- ntfs_debug("Before inner while loop: buf_size %i, lcn 0x%llx, "
- "bmp_pos 0x%llx, need_writeback %i.", buf_size,
- (unsigned long long)lcn,
- (unsigned long long)bmp_pos, need_writeback);
- while (lcn < buf_size && lcn + bmp_pos < zone_end) {
- byte = buf + (lcn >> 3);
- ntfs_debug("In inner while loop: buf_size %i, "
- "lcn 0x%llx, bmp_pos 0x%llx, "
- "need_writeback %i, byte ofs 0x%x, "
- "*byte 0x%x.", buf_size,
- (unsigned long long)lcn,
- (unsigned long long)bmp_pos,
- need_writeback,
- (unsigned int)(lcn >> 3),
- (unsigned int)*byte);
- /* Skip full bytes. */
- if (*byte == 0xff) {
- lcn = (lcn + 8) & ~(LCN)7;
- ntfs_debug("Continuing while loop 1.");
- continue;
- }
- bit = 1 << (lcn & 7);
- ntfs_debug("bit 0x%x.", bit);
- /* If the bit is already set, go onto the next one. */
- if (*byte & bit) {
- lcn++;
- ntfs_debug("Continuing while loop 2.");
- continue;
- }
- /*
- * Allocate more memory if needed, including space for
- * the terminator element.
- * ntfs_malloc_nofs() operates on whole pages only.
- */
- if ((rlpos + 2) * sizeof(*rl) > rlsize) {
- runlist_element *rl2;
-
- ntfs_debug("Reallocating memory.");
- if (!rl)
- ntfs_debug("First free bit is at LCN "
- "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.");
- /* Empty zone. Don't bother searching it. */
- goto done_zones_check;
- }
- ntfs_debug("Continuing outer while loop.");
- continue;
- } /* done_zones == 7 */
- ntfs_debug("All zones are finished.");
- /*
- * All zones are finished! If DATA_ZONE, shrink mft zone. If
- * MFT_ZONE, we have really run out of space.
- */
- mft_zone_size = vol->mft_zone_end - vol->mft_zone_start;
- ntfs_debug("vol->mft_zone_start 0x%llx, vol->mft_zone_end "
- "0x%llx, mft_zone_size 0x%llx.",
- (unsigned long long)vol->mft_zone_start,
- (unsigned long long)vol->mft_zone_end,
- (unsigned long long)mft_zone_size);
- if (zone == MFT_ZONE || mft_zone_size <= 0) {
- ntfs_debug("No free clusters left, going to out.");
- /* Really no more space left on device. */
- err = -ENOSPC;
- goto out;
- } /* zone == DATA_ZONE && mft_zone_size > 0 */
- ntfs_debug("Shrinking mft zone.");
- zone_end = vol->mft_zone_end;
- mft_zone_size >>= 1;
- if (mft_zone_size > 0)
- vol->mft_zone_end = vol->mft_zone_start + mft_zone_size;
- else /* mft zone and data2 zone no longer exist. */
- vol->data2_zone_pos = vol->mft_zone_start =
- vol->mft_zone_end = 0;
- if (vol->mft_zone_pos >= vol->mft_zone_end) {
- vol->mft_zone_pos = vol->mft_lcn;
- if (!vol->mft_zone_end)
- vol->mft_zone_pos = 0;
- }
- bmp_pos = zone_start = bmp_initial_pos =
- vol->data1_zone_pos = vol->mft_zone_end;
- search_zone = 2;
- pass = 2;
- done_zones &= ~2;
- ntfs_debug("After shrinking mft zone, mft_zone_size 0x%llx, "
- "vol->mft_zone_start 0x%llx, "
- "vol->mft_zone_end 0x%llx, "
- "vol->mft_zone_pos 0x%llx, search_zone 2, "
- "pass 2, dones_zones 0x%x, zone_start 0x%llx, "
- "zone_end 0x%llx, vol->data1_zone_pos 0x%llx, "
- "continuing outer while loop.",
- (unsigned long long)mft_zone_size,
- (unsigned long long)vol->mft_zone_start,
- (unsigned long long)vol->mft_zone_end,
- (unsigned long long)vol->mft_zone_pos,
- done_zones, (unsigned long long)zone_start,
- (unsigned long long)zone_end,
- (unsigned long long)vol->data1_zone_pos);
- }
- ntfs_debug("After outer while loop.");
-out:
- ntfs_debug("At out.");
- /* Add runlist terminator element. */
- if (likely(rl)) {
- rl[rlpos].vcn = rl[rlpos - 1].vcn + rl[rlpos - 1].length;
- rl[rlpos].lcn = is_extension ? LCN_ENOENT : LCN_RL_NOT_MAPPED;
- rl[rlpos].length = 0;
- }
- if (likely(page && !IS_ERR(page))) {
- if (need_writeback) {
- ntfs_debug("Marking page dirty.");
- flush_dcache_page(page);
- set_page_dirty(page);
- need_writeback = 0;
- }
- ntfs_unmap_page(page);
- }
- if (likely(!err)) {
- up_write(&vol->lcnbmp_lock);
- ntfs_debug("Done.");
- return rl;
- }
- ntfs_error(vol->sb, "Failed to allocate clusters, aborting "
- "(error %i).", err);
- if (rl) {
- int err2;
-
- if (err == -ENOSPC)
- ntfs_debug("Not enough space to complete allocation, "
- "err -ENOSPC, first free lcn 0x%llx, "
- "could allocate up to 0x%llx "
- "clusters.",
- (unsigned long long)rl[0].lcn,
- (unsigned long long)(count - clusters));
- /* Deallocate all allocated clusters. */
- ntfs_debug("Attempting rollback...");
- err2 = ntfs_cluster_free_from_rl_nolock(vol, rl);
- if (err2) {
- ntfs_error(vol->sb, "Failed to rollback (error %i). "
- "Leaving inconsistent metadata! "
- "Unmount and run chkdsk.", err2);
- NVolSetErrors(vol);
- }
- /* Free the runlist. */
- ntfs_free(rl);
- } else if (err == -ENOSPC)
- ntfs_debug("No space left at all, err = -ENOSPC, first free "
- "lcn = 0x%llx.",
- (long long)vol->data1_zone_pos);
- up_write(&vol->lcnbmp_lock);
- return ERR_PTR(err);
-}
-
-/**
- * __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
- * @is_rollback: true if this is a rollback operation
- *
- * Free @count clusters starting at the cluster @start_vcn in the runlist
- * described by the vfs 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.
- *
- * 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, 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.
- * - 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.
- */
-s64 __ntfs_cluster_free(ntfs_inode *ni, const VCN start_vcn, s64 count,
- ntfs_attr_search_ctx *ctx, const bool is_rollback)
-{
- s64 delta, to_free, total_freed, real_freed;
- ntfs_volume *vol;
- struct inode *lcnbmp_vi;
- runlist_element *rl;
- int err;
-
- BUG_ON(!ni);
- ntfs_debug("Entering for i_ino 0x%lx, start_vcn 0x%llx, count "
- "0x%llx.%s", ni->mft_no, (unsigned long long)start_vcn,
- (unsigned long long)count,
- is_rollback ? " (rollback)" : "");
- vol = ni->vol;
- lcnbmp_vi = vol->lcnbmp_ino;
- BUG_ON(!lcnbmp_vi);
- BUG_ON(start_vcn < 0);
- BUG_ON(count < -1);
- /*
- * Lock the lcn bitmap for writing but only if not rolling back. We
- * must hold the lock all the way including through rollback otherwise
- * rollback is not possible because once we have cleared a bit and
- * dropped the lock, anyone could have set the bit again, thus
- * allocating the cluster for another use.
- */
- if (likely(!is_rollback))
- down_write(&vol->lcnbmp_lock);
-
- total_freed = real_freed = 0;
-
- 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 "
- "element (error %li), aborting.",
- PTR_ERR(rl));
- err = PTR_ERR(rl);
- goto err_out;
- }
- if (unlikely(rl->lcn < LCN_HOLE)) {
- if (!is_rollback)
- ntfs_error(vol->sb, "First runlist element has "
- "invalid lcn, aborting.");
- err = -EIO;
- goto err_out;
- }
- /* Find the starting cluster inside the run that needs freeing. */
- delta = start_vcn - rl->vcn;
-
- /* The number of clusters in this run that need freeing. */
- to_free = rl->length - delta;
- if (count >= 0 && to_free > count)
- to_free = count;
-
- if (likely(rl->lcn >= 0)) {
- /* Do the actual freeing of the clusters in this run. */
- err = ntfs_bitmap_set_bits_in_run(lcnbmp_vi, rl->lcn + delta,
- to_free, likely(!is_rollback) ? 0 : 1);
- if (unlikely(err)) {
- if (!is_rollback)
- ntfs_error(vol->sb, "Failed to clear first run "
- "(error %i), aborting.", err);
- goto err_out;
- }
- /* We have freed @to_free real clusters. */
- real_freed = to_free;
- };
- /* Go to the next run and adjust the number of clusters left to free. */
- ++rl;
- if (count >= 0)
- count -= to_free;
-
- /* Keep track of the total "freed" clusters, including sparse ones. */
- total_freed = to_free;
- /*
- * Loop over the remaining runs, using @count as a capping value, and
- * free them.
- */
- for (; rl->length && count != 0; ++rl) {
- if (unlikely(rl->lcn < LCN_HOLE)) {
- VCN vcn;
-
- /* Attempt to map runlist. */
- vcn = rl->vcn;
- rl = ntfs_attr_find_vcn_nolock(ni, vcn, ctx);
- if (IS_ERR(rl)) {
- err = PTR_ERR(rl);
- if (!is_rollback)
- ntfs_error(vol->sb, "Failed to map "
- "runlist fragment or "
- "failed to find "
- "subsequent runlist "
- "element.");
- goto err_out;
- }
- if (unlikely(rl->lcn < LCN_HOLE)) {
- if (!is_rollback)
- ntfs_error(vol->sb, "Runlist element "
- "has invalid lcn "
- "(0x%llx).",
- (unsigned long long)
- rl->lcn);
- err = -EIO;
- goto err_out;
- }
- }
- /* The number of clusters in this run that need freeing. */
- to_free = rl->length;
- if (count >= 0 && to_free > count)
- to_free = count;
-
- if (likely(rl->lcn >= 0)) {
- /* Do the actual freeing of the clusters in the run. */
- err = ntfs_bitmap_set_bits_in_run(lcnbmp_vi, rl->lcn,
- to_free, likely(!is_rollback) ? 0 : 1);
- if (unlikely(err)) {
- if (!is_rollback)
- ntfs_error(vol->sb, "Failed to clear "
- "subsequent run.");
- goto err_out;
- }
- /* We have freed @to_free real clusters. */
- real_freed += to_free;
- }
- /* Adjust the number of clusters left to free. */
- if (count >= 0)
- count -= to_free;
-
- /* Update the total done clusters. */
- total_freed += to_free;
- }
- if (likely(!is_rollback))
- up_write(&vol->lcnbmp_lock);
-
- BUG_ON(count > 0);
-
- /* We are done. Return the number of actually freed clusters. */
- ntfs_debug("Done.");
- return real_freed;
-err_out:
- if (is_rollback)
- return err;
- /* If no real clusters were freed, no need to rollback. */
- if (!real_freed) {
- up_write(&vol->lcnbmp_lock);
- return err;
- }
- /*
- * Attempt to rollback and if that succeeds just return the error code.
- * 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, ctx, true);
- if (delta < 0) {
- ntfs_error(vol->sb, "Failed to rollback (error %i). Leaving "
- "inconsistent metadata! Unmount and run "
- "chkdsk.", (int)delta);
- NVolSetErrors(vol);
- }
- up_write(&vol->lcnbmp_lock);
- ntfs_error(vol->sb, "Aborting (error %i).", err);
- return err;
-}
-
-#endif /* NTFS_RW */
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-09 18:39:24 +0000