[PATCH 35/37] Re: [2.6-BK-URL] NTFS: 2.1.21 - Big update with race/bugfixes
From: Anton Altaparmakov
Date: Tue Oct 19 2004 - 05:32:19 EST
This is patch 35/37 in the series. It contains the following ChangeSet:
<aia21@xxxxxxxxxx> (04/10/16 1.2055)
NTFS: Add fs/ntfs/mft.[hc]::ntfs_mft_record_alloc() and various helper
functions used by it.
Signed-off-by: Anton Altaparmakov <aia21@xxxxxxxxxx>
Best regards,
Anton
--
Anton Altaparmakov <aia21 at cam.ac.uk> (replace at with @)
Unix Support, Computing Service, University of Cambridge, CB2 3QH, UK
Linux NTFS maintainer / IRC: #ntfs on irc.freenode.net
WWW: http://linux-ntfs.sf.net/, http://www-stu.christs.cam.ac.uk/~aia21/
===================================================================
diff -Nru a/fs/ntfs/ChangeLog b/fs/ntfs/ChangeLog
--- a/fs/ntfs/ChangeLog 2004-10-19 10:15:13 +01:00
+++ b/fs/ntfs/ChangeLog 2004-10-19 10:15:13 +01:00
@@ -136,6 +136,8 @@
- Add helpers fs/ntfs/layout.h::MK_MREF() and MK_LE_MREF().
- Modify fs/ntfs/mft.c::map_extent_mft_record() to only verify the mft
record sequence number if it is specified (i.e. not zero).
+ - Add fs/ntfs/mft.[hc]::ntfs_mft_record_alloc() and various helper
+ functions used by it.
2.1.20 - Fix two stupid bugs introduced in 2.1.18 release.
diff -Nru a/fs/ntfs/mft.c b/fs/ntfs/mft.c
--- a/fs/ntfs/mft.c 2004-10-19 10:15:13 +01:00
+++ b/fs/ntfs/mft.c 2004-10-19 10:15:13 +01:00
@@ -996,6 +996,1579 @@
"chkdsk.";
/**
+ * ntfs_mft_bitmap_find_and_alloc_free_rec_nolock - see name
+ * @vol: volume on which to search for a free mft record
+ * @base_ni: open base inode if allocating an extent mft record or NULL
+ *
+ * Search for a free mft record in the mft bitmap attribute on the ntfs volume
+ * @vol.
+ *
+ * If @base_ni is NULL start the search at the default allocator position.
+ *
+ * If @base_ni is not NULL start the search at the mft record after the base
+ * mft record @base_ni.
+ *
+ * Return the free mft record on success and -errno on error. An error code of
+ * -ENOSPC means that there are no free mft records in the currently
+ * initialized mft bitmap.
+ *
+ * Locking: Caller must hold vol->mftbmp_lock for writing.
+ */
+static int ntfs_mft_bitmap_find_and_alloc_free_rec_nolock(ntfs_volume *vol,
+ ntfs_inode *base_ni)
+{
+ s64 pass_end, ll, data_pos, pass_start, ofs, bit;
+ struct address_space *mftbmp_mapping;
+ u8 *buf, *byte;
+ struct page *page;
+ unsigned int page_ofs, size;
+ u8 pass, b;
+
+ ntfs_debug("Searching for free mft record in the currently "
+ "initialized mft bitmap.");
+ mftbmp_mapping = vol->mftbmp_ino->i_mapping;
+ /*
+ * Set the end of the pass making sure we do not overflow the mft
+ * bitmap.
+ */
+ pass_end = NTFS_I(vol->mft_ino)->allocated_size >>
+ vol->mft_record_size_bits;
+ ll = NTFS_I(vol->mftbmp_ino)->initialized_size << 3;
+ if (pass_end > ll)
+ pass_end = ll;
+ pass = 1;
+ if (!base_ni)
+ data_pos = vol->mft_data_pos;
+ else
+ data_pos = base_ni->mft_no + 1;
+ if (data_pos < 24)
+ data_pos = 24;
+ if (data_pos >= pass_end) {
+ data_pos = 24;
+ pass = 2;
+ /* This happens on a freshly formatted volume. */
+ if (data_pos >= pass_end)
+ return -ENOSPC;
+ }
+ pass_start = data_pos;
+ ntfs_debug("Starting bitmap search: pass %u, pass_start 0x%llx, "
+ "pass_end 0x%llx, data_pos 0x%llx.", pass,
+ (long long)pass_start, (long long)pass_end,
+ (long long)data_pos);
+ /* Loop until a free mft record is found. */
+ for (; pass <= 2;) {
+ /* Cap size to pass_end. */
+ ofs = data_pos >> 3;
+ page_ofs = ofs & ~PAGE_CACHE_MASK;
+ size = PAGE_CACHE_SIZE - page_ofs;
+ ll = ((pass_end + 7) >> 3) - ofs;
+ if (size > ll)
+ size = ll;
+ size <<= 3;
+ /*
+ * If we are still within the active pass, search the next page
+ * for a zero bit.
+ */
+ if (size) {
+ page = ntfs_map_page(mftbmp_mapping,
+ ofs >> PAGE_CACHE_SHIFT);
+ if (unlikely(IS_ERR(page))) {
+ ntfs_error(vol->sb, "Failed to read mft "
+ "bitmap, aborting.");
+ return PTR_ERR(page);
+ }
+ buf = (u8*)page_address(page) + page_ofs;
+ bit = data_pos & 7;
+ data_pos &= ~7ull;
+ ntfs_debug("Before inner for loop: size 0x%x, "
+ "data_pos 0x%llx, bit 0x%llx", size,
+ (long long)data_pos, (long long)bit);
+ for (; bit < size && data_pos + bit < pass_end;
+ bit &= ~7ull, bit += 8) {
+ byte = buf + (bit >> 3);
+ if (*byte == 0xff)
+ continue;
+ b = ffz((unsigned long)*byte);
+ if (b < 8 && b >= (bit & 7)) {
+ ll = data_pos + (bit & ~7ull) + b;
+ if (unlikely(ll > (1ll << 32))) {
+ ntfs_unmap_page(page);
+ return -ENOSPC;
+ }
+ *byte |= 1 << b;
+ flush_dcache_page(page);
+ set_page_dirty(page);
+ ntfs_unmap_page(page);
+ ntfs_debug("Done. (Found and "
+ "allocated mft record "
+ "0x%llx.)",
+ (long long)ll);
+ return ll;
+ }
+ }
+ ntfs_debug("After inner for loop: size 0x%x, "
+ "data_pos 0x%llx, bit 0x%llx", size,
+ (long long)data_pos, (long long)bit);
+ data_pos += size;
+ ntfs_unmap_page(page);
+ /*
+ * If the end of the pass has not been reached yet,
+ * continue searching the mft bitmap for a zero bit.
+ */
+ if (data_pos < pass_end)
+ continue;
+ }
+ /* Do the next pass. */
+ if (++pass == 2) {
+ /*
+ * Starting the second pass, in which we scan the first
+ * part of the zone which we omitted earlier.
+ */
+ pass_end = pass_start;
+ data_pos = pass_start = 24;
+ ntfs_debug("pass %i, pass_start 0x%llx, pass_end "
+ "0x%llx.", pass, (long long)pass_start,
+ (long long)pass_end);
+ if (data_pos >= pass_end)
+ break;
+ }
+ }
+ /* No free mft records in currently initialized mft bitmap. */
+ ntfs_debug("Done. (No free mft records left in currently initialized "
+ "mft bitmap.)");
+ return -ENOSPC;
+}
+
+/**
+ * ntfs_mft_bitmap_extend_allocation_nolock - extend mft bitmap by a cluster
+ * @vol: volume on which to extend the mft bitmap attribute
+ *
+ * Extend the mft bitmap attribute on the ntfs volume @vol by one cluster.
+ *
+ * Note: Only changes allocated_size, i.e. does not touch initialized_size or
+ * data_size.
+ *
+ * Return 0 on success and -errno on error.
+ *
+ * Locking: - Caller must hold vol->mftbmp_lock for writing.
+ * - This function takes NTFS_I(vol->mftbmp_ino)->runlist.lock for
+ * writing and releases it before returning.
+ * - This function takes vol->lcnbmp_lock for writing and releases it
+ * before returning.
+ */
+static int ntfs_mft_bitmap_extend_allocation_nolock(ntfs_volume *vol)
+{
+ LCN lcn;
+ s64 ll;
+ struct page *page;
+ ntfs_inode *mft_ni, *mftbmp_ni;
+ runlist_element *rl, *rl2 = NULL;
+ ntfs_attr_search_ctx *ctx = NULL;
+ MFT_RECORD *mrec;
+ ATTR_RECORD *a = NULL;
+ int ret, mp_size;
+ u32 old_alen = 0;
+ u8 *b, tb;
+ struct {
+ u8 added_cluster:1;
+ u8 added_run:1;
+ u8 mp_rebuilt:1;
+ } status = { 0, 0, 0 };
+
+ ntfs_debug("Extending mft bitmap allocation.");
+ mft_ni = NTFS_I(vol->mft_ino);
+ mftbmp_ni = NTFS_I(vol->mftbmp_ino);
+ /*
+ * Determine the last lcn of the mft bitmap. The allocated size of the
+ * mft bitmap cannot be zero so we are ok to do this.
+ * ntfs_find_vcn() returns the runlist locked on success.
+ */
+ rl = ntfs_find_vcn(mftbmp_ni, (mftbmp_ni->allocated_size - 1) >>
+ vol->cluster_size_bits, TRUE);
+ if (unlikely(IS_ERR(rl) || !rl->length || rl->lcn < 0)) {
+ ntfs_error(vol->sb, "Failed to determine last allocated "
+ "cluster of mft bitmap attribute.");
+ if (!IS_ERR(rl)) {
+ up_write(&mftbmp_ni->runlist.lock);
+ ret = -EIO;
+ } else
+ ret = PTR_ERR(rl);
+ return ret;
+ }
+ lcn = rl->lcn + rl->length;
+ ntfs_debug("Last lcn of mft bitmap attribute is 0x%llx.",
+ (long long)lcn);
+ /*
+ * Attempt to get the cluster following the last allocated cluster by
+ * hand as it may be in the MFT zone so the allocator would not give it
+ * to us.
+ */
+ ll = lcn >> 3;
+ page = ntfs_map_page(vol->lcnbmp_ino->i_mapping,
+ ll >> PAGE_CACHE_SHIFT);
+ if (IS_ERR(page)) {
+ up_write(&mftbmp_ni->runlist.lock);
+ ntfs_error(vol->sb, "Failed to read from lcn bitmap.");
+ return PTR_ERR(page);
+ }
+ b = (u8*)page_address(page) + (ll & ~PAGE_CACHE_MASK);
+ tb = 1 << (lcn & 7ull);
+ down_write(&vol->lcnbmp_lock);
+ if (*b != 0xff && !(*b & tb)) {
+ /* Next cluster is free, allocate it. */
+ *b |= tb;
+ flush_dcache_page(page);
+ set_page_dirty(page);
+ up_write(&vol->lcnbmp_lock);
+ ntfs_unmap_page(page);
+ /* Update the mft bitmap runlist. */
+ rl->length++;
+ rl[1].vcn++;
+ status.added_cluster = 1;
+ ntfs_debug("Appending one cluster to mft bitmap.");
+ } else {
+ up_write(&vol->lcnbmp_lock);
+ ntfs_unmap_page(page);
+ /* Allocate a cluster from the DATA_ZONE. */
+ rl2 = ntfs_cluster_alloc(vol, rl[1].vcn, 1, lcn, DATA_ZONE);
+ if (IS_ERR(rl2)) {
+ up_write(&mftbmp_ni->runlist.lock);
+ ntfs_error(vol->sb, "Failed to allocate a cluster for "
+ "the mft bitmap.");
+ return PTR_ERR(rl2);
+ }
+ rl = ntfs_runlists_merge(mftbmp_ni->runlist.rl, rl2);
+ if (IS_ERR(rl)) {
+ up_write(&mftbmp_ni->runlist.lock);
+ ntfs_error(vol->sb, "Failed to merge runlists for mft "
+ "bitmap.");
+ if (ntfs_cluster_free_from_rl(vol, rl2)) {
+ ntfs_error(vol->sb, "Failed to dealocate "
+ "allocated cluster.%s", es);
+ NVolSetErrors(vol);
+ }
+ ntfs_free(rl2);
+ return PTR_ERR(rl);
+ }
+ mftbmp_ni->runlist.rl = rl;
+ status.added_run = 1;
+ ntfs_debug("Adding one run to mft bitmap.");
+ /* Find the last run in the new runlist. */
+ for (; rl[1].length; rl++)
+ ;
+ }
+ /*
+ * Update the attribute record as well. Note: @rl is the last
+ * (non-terminator) runlist element of mft bitmap.
+ */
+ mrec = map_mft_record(mft_ni);
+ if (IS_ERR(mrec)) {
+ ntfs_error(vol->sb, "Failed to map mft record.");
+ ret = PTR_ERR(mrec);
+ goto undo_alloc;
+ }
+ ctx = ntfs_attr_get_search_ctx(mft_ni, mrec);
+ if (unlikely(!ctx)) {
+ ntfs_error(vol->sb, "Failed to get search context.");
+ ret = -ENOMEM;
+ goto undo_alloc;
+ }
+ ret = ntfs_attr_lookup(mftbmp_ni->type, mftbmp_ni->name,
+ mftbmp_ni->name_len, CASE_SENSITIVE, rl[1].vcn, NULL,
+ 0, ctx);
+ if (unlikely(ret)) {
+ ntfs_error(vol->sb, "Failed to find last attribute extent of "
+ "mft bitmap attribute.");
+ if (ret == -ENOENT)
+ ret = -EIO;
+ goto undo_alloc;
+ }
+ a = ctx->attr;
+ ll = sle64_to_cpu(a->data.non_resident.lowest_vcn);
+ /* Search back for the previous last allocated cluster of mft bitmap. */
+ for (rl2 = rl; rl2 > mftbmp_ni->runlist.rl; rl2--) {
+ if (ll >= rl2->vcn)
+ break;
+ }
+ BUG_ON(ll < rl2->vcn);
+ BUG_ON(ll >= rl2->vcn + rl2->length);
+ /* Get the size for the new mapping pairs array for this extent. */
+ mp_size = ntfs_get_size_for_mapping_pairs(vol, rl2, ll);
+ if (unlikely(mp_size <= 0)) {
+ ntfs_error(vol->sb, "Get size for mapping pairs failed for "
+ "mft bitmap attribute extent.");
+ ret = mp_size;
+ if (!ret)
+ ret = -EIO;
+ goto undo_alloc;
+ }
+ /* Expand the attribute record if necessary. */
+ old_alen = le32_to_cpu(a->length);
+ ret = ntfs_attr_record_resize(ctx->mrec, a, mp_size +
+ le16_to_cpu(a->data.non_resident.mapping_pairs_offset));
+ if (unlikely(ret)) {
+ if (ret != -ENOSPC) {
+ ntfs_error(vol->sb, "Failed to resize attribute "
+ "record for mft bitmap attribute.");
+ goto undo_alloc;
+ }
+ // TODO: Deal with this by moving this extent to a new mft
+ // record or by starting a new extent in a new mft record or by
+ // moving other attributes out of this mft record.
+ ntfs_error(vol->sb, "Not enough space in this mft record to "
+ "accomodate extended mft bitmap attribute "
+ "extent. Cannot handle this yet.");
+ ret = -EOPNOTSUPP;
+ goto undo_alloc;
+ }
+ status.mp_rebuilt = 1;
+ /* Generate the mapping pairs array directly into the attr record. */
+ ret = ntfs_mapping_pairs_build(vol, (u8*)a +
+ le16_to_cpu(a->data.non_resident.mapping_pairs_offset),
+ mp_size, rl2, ll, NULL);
+ if (unlikely(ret)) {
+ ntfs_error(vol->sb, "Failed to build mapping pairs array for "
+ "mft bitmap attribute.");
+ goto undo_alloc;
+ }
+ /* Update the highest_vcn. */
+ a->data.non_resident.highest_vcn = cpu_to_sle64(rl[1].vcn - 1);
+ /*
+ * We now have extended the mft bitmap allocated_size by one cluster.
+ * Reflect this in the ntfs_inode structure and the attribute record.
+ */
+ if (a->data.non_resident.lowest_vcn) {
+ /*
+ * We are not in the first attribute extent, switch to it, but
+ * first ensure the changes will make it to disk later.
+ */
+ flush_dcache_mft_record_page(ctx->ntfs_ino);
+ mark_mft_record_dirty(ctx->ntfs_ino);
+ ntfs_attr_reinit_search_ctx(ctx);
+ ret = ntfs_attr_lookup(mftbmp_ni->type, mftbmp_ni->name,
+ mftbmp_ni->name_len, CASE_SENSITIVE, 0, NULL,
+ 0, ctx);
+ if (unlikely(ret)) {
+ ntfs_error(vol->sb, "Failed to find first attribute "
+ "extent of mft bitmap attribute.");
+ goto restore_undo_alloc;
+ }
+ a = ctx->attr;
+ }
+ mftbmp_ni->allocated_size += vol->cluster_size;
+ a->data.non_resident.allocated_size =
+ cpu_to_sle64(mftbmp_ni->allocated_size);
+ /* Ensure the changes make it to disk. */
+ flush_dcache_mft_record_page(ctx->ntfs_ino);
+ mark_mft_record_dirty(ctx->ntfs_ino);
+ ntfs_attr_put_search_ctx(ctx);
+ unmap_mft_record(mft_ni);
+ up_write(&mftbmp_ni->runlist.lock);
+ ntfs_debug("Done.");
+ return 0;
+restore_undo_alloc:
+ ntfs_attr_reinit_search_ctx(ctx);
+ if (ntfs_attr_lookup(mftbmp_ni->type, mftbmp_ni->name,
+ mftbmp_ni->name_len, CASE_SENSITIVE, rl[1].vcn, NULL,
+ 0, ctx)) {
+ ntfs_error(vol->sb, "Failed to find last attribute extent of "
+ "mft bitmap attribute.%s", es);
+ mftbmp_ni->allocated_size += vol->cluster_size;
+ ntfs_attr_put_search_ctx(ctx);
+ unmap_mft_record(mft_ni);
+ up_write(&mftbmp_ni->runlist.lock);
+ /*
+ * The only thing that is now wrong is ->allocated_size of the
+ * base attribute extent which chkdsk should be able to fix.
+ */
+ NVolSetErrors(vol);
+ return ret;
+ }
+ a = ctx->attr;
+ a->data.non_resident.highest_vcn = cpu_to_sle64(rl[1].vcn - 2);
+undo_alloc:
+ if (status.added_cluster) {
+ /* Truncate the last run in the runlist by one cluster. */
+ rl->length--;
+ rl[1].vcn--;
+ } else if (status.added_run) {
+ lcn = rl->lcn;
+ /* Remove the last run from the runlist. */
+ rl->lcn = rl[1].lcn;
+ rl->length = 0;
+ }
+ /* Deallocate the cluster. */
+ down_write(&vol->lcnbmp_lock);
+ if (ntfs_bitmap_clear_bit(vol->lcnbmp_ino, lcn)) {
+ ntfs_error(vol->sb, "Failed to free allocated cluster.%s", es);
+ NVolSetErrors(vol);
+ }
+ up_write(&vol->lcnbmp_lock);
+ if (status.mp_rebuilt) {
+ if (ntfs_mapping_pairs_build(vol, (u8*)a + le16_to_cpu(
+ a->data.non_resident.mapping_pairs_offset),
+ old_alen - le16_to_cpu(
+ a->data.non_resident.mapping_pairs_offset),
+ rl2, ll, NULL)) {
+ ntfs_error(vol->sb, "Failed to restore mapping pairs "
+ "array.%s", es);
+ NVolSetErrors(vol);
+ }
+ if (ntfs_attr_record_resize(ctx->mrec, a, old_alen)) {
+ ntfs_error(vol->sb, "Failed to restore attribute "
+ "record.%s", es);
+ NVolSetErrors(vol);
+ }
+ flush_dcache_mft_record_page(ctx->ntfs_ino);
+ mark_mft_record_dirty(ctx->ntfs_ino);
+ }
+ if (ctx)
+ ntfs_attr_put_search_ctx(ctx);
+ if (!IS_ERR(mrec))
+ unmap_mft_record(mft_ni);
+ up_write(&mftbmp_ni->runlist.lock);
+ return ret;
+}
+
+/**
+ * ntfs_mft_bitmap_extend_initialized_nolock - extend mftbmp initialized data
+ * @vol: volume on which to extend the mft bitmap attribute
+ *
+ * Extend the initialized portion of the mft bitmap attribute on the ntfs
+ * volume @vol by 8 bytes.
+ *
+ * Note: Only changes initialized_size and data_size, i.e. requires that
+ * allocated_size is big enough to fit the new initialized_size.
+ *
+ * Return 0 on success and -error on error.
+ *
+ * Locking: Caller must hold vol->mftbmp_lock for writing.
+ */
+static int ntfs_mft_bitmap_extend_initialized_nolock(ntfs_volume *vol)
+{
+ s64 old_data_size, old_initialized_size;
+ struct inode *mftbmp_vi;
+ ntfs_inode *mft_ni, *mftbmp_ni;
+ ntfs_attr_search_ctx *ctx;
+ MFT_RECORD *mrec;
+ ATTR_RECORD *a;
+ int ret;
+
+ ntfs_debug("Extending mft bitmap initiailized (and data) size.");
+ mft_ni = NTFS_I(vol->mft_ino);
+ mftbmp_vi = vol->mftbmp_ino;
+ mftbmp_ni = NTFS_I(mftbmp_vi);
+ /* Get the attribute record. */
+ mrec = map_mft_record(mft_ni);
+ if (IS_ERR(mrec)) {
+ ntfs_error(vol->sb, "Failed to map mft record.");
+ return PTR_ERR(mrec);
+ }
+ ctx = ntfs_attr_get_search_ctx(mft_ni, mrec);
+ if (unlikely(!ctx)) {
+ ntfs_error(vol->sb, "Failed to get search context.");
+ ret = -ENOMEM;
+ goto unm_err_out;
+ }
+ ret = ntfs_attr_lookup(mftbmp_ni->type, mftbmp_ni->name,
+ mftbmp_ni->name_len, CASE_SENSITIVE, 0, NULL, 0, ctx);
+ if (unlikely(ret)) {
+ ntfs_error(vol->sb, "Failed to find first attribute extent of "
+ "mft bitmap attribute.");
+ if (ret == -ENOENT)
+ ret = -EIO;
+ goto put_err_out;
+ }
+ a = ctx->attr;
+ old_data_size = mftbmp_vi->i_size;
+ old_initialized_size = mftbmp_ni->initialized_size;
+ /*
+ * We can simply update the initialized_size before filling the space
+ * with zeroes because the caller is holding the mft bitmap lock for
+ * writing which ensures that no one else is trying to access the data.
+ */
+ mftbmp_ni->initialized_size += 8;
+ a->data.non_resident.initialized_size =
+ cpu_to_sle64(mftbmp_ni->initialized_size);
+ if (mftbmp_ni->initialized_size > mftbmp_vi->i_size) {
+ mftbmp_vi->i_size = mftbmp_ni->initialized_size;
+ a->data.non_resident.data_size =
+ cpu_to_sle64(mftbmp_vi->i_size);
+ }
+ /* Ensure the changes make it to disk. */
+ flush_dcache_mft_record_page(ctx->ntfs_ino);
+ mark_mft_record_dirty(ctx->ntfs_ino);
+ ntfs_attr_put_search_ctx(ctx);
+ unmap_mft_record(mft_ni);
+ /* Initialize the mft bitmap attribute value with zeroes. */
+ ret = ntfs_attr_set(mftbmp_ni, old_initialized_size, 8, 0);
+ if (likely(!ret)) {
+ ntfs_debug("Done. (Wrote eight initialized bytes to mft "
+ "bitmap.");
+ return 0;
+ }
+ ntfs_error(vol->sb, "Failed to write to mft bitmap.");
+ /* Try to recover from the error. */
+ mrec = map_mft_record(mft_ni);
+ if (IS_ERR(mrec)) {
+ ntfs_error(vol->sb, "Failed to map mft record.%s", es);
+ NVolSetErrors(vol);
+ return ret;
+ }
+ ctx = ntfs_attr_get_search_ctx(mft_ni, mrec);
+ if (unlikely(!ctx)) {
+ ntfs_error(vol->sb, "Failed to get search context.%s", es);
+ NVolSetErrors(vol);
+ goto unm_err_out;
+ }
+ if (ntfs_attr_lookup(mftbmp_ni->type, mftbmp_ni->name,
+ mftbmp_ni->name_len, CASE_SENSITIVE, 0, NULL, 0, ctx)) {
+ ntfs_error(vol->sb, "Failed to find first attribute extent of "
+ "mft bitmap attribute.%s", es);
+ NVolSetErrors(vol);
+put_err_out:
+ ntfs_attr_put_search_ctx(ctx);
+unm_err_out:
+ unmap_mft_record(mft_ni);
+ goto err_out;
+ }
+ a = ctx->attr;
+ mftbmp_ni->initialized_size = old_initialized_size;
+ a->data.non_resident.initialized_size =
+ cpu_to_sle64(old_initialized_size);
+ if (mftbmp_vi->i_size != old_data_size) {
+ mftbmp_vi->i_size = old_data_size;
+ a->data.non_resident.data_size = cpu_to_sle64(old_data_size);
+ }
+ flush_dcache_mft_record_page(ctx->ntfs_ino);
+ mark_mft_record_dirty(ctx->ntfs_ino);
+ ntfs_attr_put_search_ctx(ctx);
+ unmap_mft_record(mft_ni);
+ ntfs_debug("Restored status of mftbmp: allocated_size 0x%llx, "
+ "data_size 0x%llx, initialized_size 0x%llx.",
+ (long long)mftbmp_ni->allocated_size,
+ (long long)mftbmp_vi->i_size,
+ (long long)mftbmp_ni->initialized_size);
+err_out:
+ return ret;
+}
+
+/**
+ * ntfs_mft_data_extend_allocation_nolock - extend mft data attribute
+ * @vol: volume on which to extend the mft data attribute
+ *
+ * Extend the mft data attribute on the ntfs volume @vol by 16 mft records
+ * worth of clusters or if not enough space for this by one mft record worth
+ * of clusters.
+ *
+ * Note: Only changes allocated_size, i.e. does not touch initialized_size or
+ * data_size.
+ *
+ * Return 0 on success and -errno on error.
+ *
+ * Locking: - Caller must hold vol->mftbmp_lock for writing.
+ * - This function takes NTFS_I(vol->mft_ino)->runlist.lock for
+ * writing and releases it before returning.
+ * - This function calls functions which take vol->lcnbmp_lock for
+ * writing and release it before returning.
+ */
+static int ntfs_mft_data_extend_allocation_nolock(ntfs_volume *vol)
+{
+ LCN lcn;
+ VCN old_last_vcn;
+ s64 min_nr, nr, ll = 0;
+ ntfs_inode *mft_ni;
+ runlist_element *rl, *rl2;
+ ntfs_attr_search_ctx *ctx = NULL;
+ MFT_RECORD *mrec;
+ ATTR_RECORD *a = NULL;
+ int ret, mp_size;
+ u32 old_alen = 0;
+ BOOL mp_rebuilt = FALSE;
+
+ ntfs_debug("Extending mft data allocation.");
+ mft_ni = NTFS_I(vol->mft_ino);
+ /*
+ * Determine the preferred allocation location, i.e. the last lcn of
+ * the mft data attribute. The allocated size of the mft data
+ * attribute cannot be zero so we are ok to do this.
+ * ntfs_find_vcn() returns the runlist locked on success.
+ */
+ rl = ntfs_find_vcn(mft_ni, (mft_ni->allocated_size - 1) >>
+ vol->cluster_size_bits, TRUE);
+ if (unlikely(IS_ERR(rl) || !rl->length || rl->lcn < 0)) {
+ ntfs_error(vol->sb, "Failed to determine last allocated "
+ "cluster of mft data attribute.");
+ if (!IS_ERR(rl)) {
+ up_write(&mft_ni->runlist.lock);
+ ret = -EIO;
+ } else
+ ret = PTR_ERR(rl);
+ return ret;
+ }
+ lcn = rl->lcn + rl->length;
+ ntfs_debug("Last lcn of mft data attribute is 0x%llx.",
+ (long long)lcn);
+ /* Minimum allocation is one mft record worth of clusters. */
+ min_nr = vol->mft_record_size >> vol->cluster_size_bits;
+ if (!min_nr)
+ min_nr = 1;
+ /* Want to allocate 16 mft records worth of clusters. */
+ nr = vol->mft_record_size << 4 >> vol->cluster_size_bits;
+ if (!nr)
+ nr = min_nr;
+ /* Ensure we do not go above 2^32-1 mft records. */
+ if (unlikely((mft_ni->allocated_size +
+ (nr << vol->cluster_size_bits)) >>
+ vol->mft_record_size_bits >= (1ll << 32))) {
+ nr = min_nr;
+ if (unlikely((mft_ni->allocated_size +
+ (nr << vol->cluster_size_bits)) >>
+ vol->mft_record_size_bits >= (1ll << 32))) {
+ ntfs_warning(vol->sb, "Cannot allocate mft record "
+ "because the maximum number of inodes "
+ "(2^32) has already been reached.");
+ up_write(&mft_ni->runlist.lock);
+ return -ENOSPC;
+ }
+ }
+ ntfs_debug("Trying mft data allocation with %s cluster count %lli.",
+ nr > min_nr ? "default" : "minimal", (long long)nr);
+ old_last_vcn = rl[1].vcn;
+ do {
+ rl2 = ntfs_cluster_alloc(vol, old_last_vcn, nr, lcn, MFT_ZONE);
+ if (likely(!IS_ERR(rl2)))
+ break;
+ if (PTR_ERR(rl2) != -ENOSPC || nr == min_nr) {
+ ntfs_error(vol->sb, "Failed to allocate the minimal "
+ "number of clusters (%lli) for the "
+ "mft data attribute.", (long long)nr);
+ up_write(&mft_ni->runlist.lock);
+ return PTR_ERR(rl2);
+ }
+ /*
+ * There is not enough space to do the allocation, but there
+ * might be enough space to do a minimal allocation so try that
+ * before failing.
+ */
+ nr = min_nr;
+ ntfs_debug("Retrying mft data allocation with minimal cluster "
+ "count %lli.", (long long)nr);
+ } while (1);
+ rl = ntfs_runlists_merge(mft_ni->runlist.rl, rl2);
+ if (IS_ERR(rl)) {
+ up_write(&mft_ni->runlist.lock);
+ ntfs_error(vol->sb, "Failed to merge runlists for mft data "
+ "attribute.");
+ if (ntfs_cluster_free_from_rl(vol, rl2)) {
+ ntfs_error(vol->sb, "Failed to dealocate clusters "
+ "from the mft data attribute.%s", es);
+ NVolSetErrors(vol);
+ }
+ ntfs_free(rl2);
+ return PTR_ERR(rl);
+ }
+ mft_ni->runlist.rl = rl;
+ ntfs_debug("Allocated %lli clusters.", nr);
+ /* Find the last run in the new runlist. */
+ for (; rl[1].length; rl++)
+ ;
+ /* Update the attribute record as well. */
+ mrec = map_mft_record(mft_ni);
+ if (IS_ERR(mrec)) {
+ ntfs_error(vol->sb, "Failed to map mft record.");
+ ret = PTR_ERR(mrec);
+ goto undo_alloc;
+ }
+ ctx = ntfs_attr_get_search_ctx(mft_ni, mrec);
+ if (unlikely(!ctx)) {
+ ntfs_error(vol->sb, "Failed to get search context.");
+ ret = -ENOMEM;
+ goto undo_alloc;
+ }
+ ret = ntfs_attr_lookup(mft_ni->type, mft_ni->name, mft_ni->name_len,
+ CASE_SENSITIVE, rl[1].vcn, NULL, 0, ctx);
+ if (unlikely(ret)) {
+ ntfs_error(vol->sb, "Failed to find last attribute extent of "
+ "mft data attribute.");
+ if (ret == -ENOENT)
+ ret = -EIO;
+ goto undo_alloc;
+ }
+ a = ctx->attr;
+ ll = sle64_to_cpu(a->data.non_resident.lowest_vcn);
+ /* Search back for the previous last allocated cluster of mft bitmap. */
+ for (rl2 = rl; rl2 > mft_ni->runlist.rl; rl2--) {
+ if (ll >= rl2->vcn)
+ break;
+ }
+ BUG_ON(ll < rl2->vcn);
+ BUG_ON(ll >= rl2->vcn + rl2->length);
+ /* Get the size for the new mapping pairs array for this extent. */
+ mp_size = ntfs_get_size_for_mapping_pairs(vol, rl2, ll);
+ if (unlikely(mp_size <= 0)) {
+ ntfs_error(vol->sb, "Get size for mapping pairs failed for "
+ "mft data attribute extent.");
+ ret = mp_size;
+ if (!ret)
+ ret = -EIO;
+ goto undo_alloc;
+ }
+ /* Expand the attribute record if necessary. */
+ old_alen = le32_to_cpu(a->length);
+ ret = ntfs_attr_record_resize(ctx->mrec, a, mp_size +
+ le16_to_cpu(a->data.non_resident.mapping_pairs_offset));
+ if (unlikely(ret)) {
+ if (ret != -ENOSPC) {
+ ntfs_error(vol->sb, "Failed to resize attribute "
+ "record for mft data attribute.");
+ goto undo_alloc;
+ }
+ // TODO: Deal with this by moving this extent to a new mft
+ // record or by starting a new extent in a new mft record or by
+ // moving other attributes out of this mft record.
+ // Note: Use the special reserved mft records and ensure that
+ // this extent is not required to find the mft record in
+ // question.
+ ntfs_error(vol->sb, "Not enough space in this mft record to "
+ "accomodate extended mft data attribute "
+ "extent. Cannot handle this yet.");
+ ret = -EOPNOTSUPP;
+ goto undo_alloc;
+ }
+ mp_rebuilt = TRUE;
+ /* Generate the mapping pairs array directly into the attr record. */
+ ret = ntfs_mapping_pairs_build(vol, (u8*)a +
+ le16_to_cpu(a->data.non_resident.mapping_pairs_offset),
+ mp_size, rl2, ll, NULL);
+ if (unlikely(ret)) {
+ ntfs_error(vol->sb, "Failed to build mapping pairs array of "
+ "mft data attribute.");
+ goto undo_alloc;
+ }
+ /* Update the highest_vcn. */
+ a->data.non_resident.highest_vcn = cpu_to_sle64(rl[1].vcn - 1);
+ /*
+ * We now have extended the mft data allocated_size by nr clusters.
+ * Reflect this in the ntfs_inode structure and the attribute record.
+ * @rl is the last (non-terminator) runlist element of mft data
+ * attribute.
+ */
+ if (a->data.non_resident.lowest_vcn) {
+ /*
+ * We are not in the first attribute extent, switch to it, but
+ * first ensure the changes will make it to disk later.
+ */
+ flush_dcache_mft_record_page(ctx->ntfs_ino);
+ mark_mft_record_dirty(ctx->ntfs_ino);
+ ntfs_attr_reinit_search_ctx(ctx);
+ ret = ntfs_attr_lookup(mft_ni->type, mft_ni->name,
+ mft_ni->name_len, CASE_SENSITIVE, 0, NULL, 0,
+ ctx);
+ if (unlikely(ret)) {
+ ntfs_error(vol->sb, "Failed to find first attribute "
+ "extent of mft data attribute.");
+ goto restore_undo_alloc;
+ }
+ a = ctx->attr;
+ }
+ mft_ni->allocated_size += nr << vol->cluster_size_bits;
+ a->data.non_resident.allocated_size =
+ cpu_to_sle64(mft_ni->allocated_size);
+ /* Ensure the changes make it to disk. */
+ flush_dcache_mft_record_page(ctx->ntfs_ino);
+ mark_mft_record_dirty(ctx->ntfs_ino);
+ ntfs_attr_put_search_ctx(ctx);
+ unmap_mft_record(mft_ni);
+ up_write(&mft_ni->runlist.lock);
+ ntfs_debug("Done.");
+ return 0;
+restore_undo_alloc:
+ ntfs_attr_reinit_search_ctx(ctx);
+ if (ntfs_attr_lookup(mft_ni->type, mft_ni->name, mft_ni->name_len,
+ CASE_SENSITIVE, rl[1].vcn, NULL, 0, ctx)) {
+ ntfs_error(vol->sb, "Failed to find last attribute extent of "
+ "mft data attribute.%s", es);
+ mft_ni->allocated_size += nr << vol->cluster_size_bits;
+ ntfs_attr_put_search_ctx(ctx);
+ unmap_mft_record(mft_ni);
+ up_write(&mft_ni->runlist.lock);
+ /*
+ * The only thing that is now wrong is ->allocated_size of the
+ * base attribute extent which chkdsk should be able to fix.
+ */
+ NVolSetErrors(vol);
+ return ret;
+ }
+ a = ctx->attr;
+ a->data.non_resident.highest_vcn = cpu_to_sle64(old_last_vcn - 1);
+undo_alloc:
+ if (ntfs_cluster_free(vol->mft_ino, old_last_vcn, -1) < 0) {
+ ntfs_error(vol->sb, "Failed to free clusters from mft data "
+ "attribute.%s", es);
+ NVolSetErrors(vol);
+ }
+ 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 (ntfs_mapping_pairs_build(vol, (u8*)a + le16_to_cpu(
+ a->data.non_resident.mapping_pairs_offset),
+ old_alen - le16_to_cpu(
+ a->data.non_resident.mapping_pairs_offset),
+ rl2, ll, NULL)) {
+ ntfs_error(vol->sb, "Failed to restore mapping pairs "
+ "array.%s", es);
+ NVolSetErrors(vol);
+ }
+ if (ntfs_attr_record_resize(ctx->mrec, a, old_alen)) {
+ ntfs_error(vol->sb, "Failed to restore attribute "
+ "record.%s", es);
+ NVolSetErrors(vol);
+ }
+ flush_dcache_mft_record_page(ctx->ntfs_ino);
+ mark_mft_record_dirty(ctx->ntfs_ino);
+ }
+ if (ctx)
+ ntfs_attr_put_search_ctx(ctx);
+ if (!IS_ERR(mrec))
+ unmap_mft_record(mft_ni);
+ up_write(&mft_ni->runlist.lock);
+ return ret;
+}
+
+/**
+ * ntfs_mft_record_layout - layout an mft record into a memory buffer
+ * @vol: volume to which the mft record will belong
+ * @mft_no: mft reference specifying the mft record number
+ * @m: destination buffer of size >= @vol->mft_record_size bytes
+ *
+ * Layout an empty, unused mft record with the mft record number @mft_no into
+ * the buffer @m. The volume @vol is needed because the mft record structure
+ * was modified in NTFS 3.1 so we need to know which volume version this mft
+ * record will be used on.
+ *
+ * Return 0 on success and -errno on error.
+ */
+static int ntfs_mft_record_layout(const ntfs_volume *vol, const s64 mft_no,
+ MFT_RECORD *m)
+{
+ ATTR_RECORD *a;
+
+ ntfs_debug("Entering for mft record 0x%llx.", (long long)mft_no);
+ if (mft_no >= (1ll << 32)) {
+ ntfs_error(vol->sb, "Mft record number 0x%llx exceeds "
+ "maximum of 2^32.", (long long)mft_no);
+ return -ERANGE;
+ }
+ /* Start by clearing the whole mft record to gives us a clean slate. */
+ memset(m, 0, vol->mft_record_size);
+ /* Aligned to 2-byte boundary. */
+ if (vol->major_ver < 3 || (vol->major_ver == 3 && !vol->minor_ver))
+ m->usa_ofs = cpu_to_le16((sizeof(MFT_RECORD_OLD) + 1) & ~1);
+ else {
+ m->usa_ofs = cpu_to_le16((sizeof(MFT_RECORD) + 1) & ~1);
+ /*
+ * Set the NTFS 3.1+ specific fields while we know that the
+ * volume version is 3.1+.
+ */
+ m->reserved = 0;
+ m->mft_record_number = cpu_to_le32((u32)mft_no);
+ }
+ m->magic = magic_FILE;
+ if (vol->mft_record_size >= NTFS_BLOCK_SIZE)
+ m->usa_count = cpu_to_le16(vol->mft_record_size /
+ NTFS_BLOCK_SIZE + 1);
+ else {
+ m->usa_count = cpu_to_le16(1);
+ ntfs_warning(vol->sb, "Sector size is bigger than mft record "
+ "size. Setting usa_count to 1. If chkdsk "
+ "reports this as corruption, please email "
+ "linux-ntfs-dev@xxxxxxxxxxxxxxxxxxxxx stating "
+ "that you saw this message and that the "
+ "modified file system created was corrupt. "
+ "Thank you.");
+ }
+ /* Set the update sequence number to 1. */
+ *(le16*)((u8*)m + le16_to_cpu(m->usa_ofs)) = cpu_to_le16(1);
+ m->lsn = 0;
+ m->sequence_number = cpu_to_le16(1);
+ m->link_count = 0;
+ /*
+ * Place the attributes straight after the update sequence array,
+ * aligned to 8-byte boundary.
+ */
+ m->attrs_offset = cpu_to_le16((le16_to_cpu(m->usa_ofs) +
+ (le16_to_cpu(m->usa_count) << 1) + 7) & ~7);
+ m->flags = 0;
+ /*
+ * Using attrs_offset plus eight bytes (for the termination attribute).
+ * attrs_offset is already aligned to 8-byte boundary, so no need to
+ * align again.
+ */
+ m->bytes_in_use = cpu_to_le32(le16_to_cpu(m->attrs_offset) + 8);
+ m->bytes_allocated = cpu_to_le32(vol->mft_record_size);
+ m->base_mft_record = 0;
+ m->next_attr_instance = 0;
+ /* Add the termination attribute. */
+ a = (ATTR_RECORD*)((u8*)m + le16_to_cpu(m->attrs_offset));
+ a->type = AT_END;
+ a->length = 0;
+ ntfs_debug("Done.");
+ return 0;
+}
+
+/**
+ * ntfs_mft_record_format - format an mft record on an ntfs volume
+ * @vol: volume on which to format the mft record
+ * @mft_no: mft record number to format
+ *
+ * Format the mft record @mft_no in $MFT/$DATA, i.e. lay out an empty, unused
+ * mft record into the appropriate place of the mft data attribute. This is
+ * used when extending the mft data attribute.
+ *
+ * Return 0 on success and -errno on error.
+ */
+static int ntfs_mft_record_format(const ntfs_volume *vol, const s64 mft_no)
+{
+ struct inode *mft_vi = vol->mft_ino;
+ struct page *page;
+ MFT_RECORD *m;
+ pgoff_t index, end_index;
+ unsigned int ofs;
+ int err;
+
+ ntfs_debug("Entering for mft record 0x%llx.", (long long)mft_no);
+ /*
+ * The index into the page cache and the offset within the page cache
+ * page of the wanted mft record.
+ */
+ index = mft_no << vol->mft_record_size_bits >> PAGE_CACHE_SHIFT;
+ ofs = (mft_no << vol->mft_record_size_bits) & ~PAGE_CACHE_MASK;
+ /* The maximum valid index into the page cache for $MFT's data. */
+ end_index = mft_vi->i_size >> PAGE_CACHE_SHIFT;
+ if (unlikely(index >= end_index)) {
+ if (unlikely(index > end_index || ofs + vol->mft_record_size >=
+ (mft_vi->i_size & ~PAGE_CACHE_MASK))) {
+ ntfs_error(vol->sb, "Tried to format non-existing mft "
+ "record 0x%llx.", (long long)mft_no);
+ return -ENOENT;
+ }
+ }
+ /* Read, map, and pin the page containing the mft record. */
+ page = ntfs_map_page(mft_vi->i_mapping, index);
+ if (unlikely(IS_ERR(page))) {
+ ntfs_error(vol->sb, "Failed to map page containing mft record "
+ "to format 0x%llx.", (long long)mft_no);
+ return PTR_ERR(page);
+ }
+ lock_page(page);
+ BUG_ON(!PageUptodate(page));
+ ClearPageUptodate(page);
+ m = (MFT_RECORD*)((u8*)page_address(page) + ofs);
+ err = ntfs_mft_record_layout(vol, mft_no, m);
+ if (unlikely(err)) {
+ ntfs_error(vol->sb, "Failed to layout mft record 0x%llx.",
+ (long long)mft_no);
+ SetPageUptodate(page);
+ unlock_page(page);
+ ntfs_unmap_page(page);
+ return err;
+ }
+ flush_dcache_page(page);
+ SetPageUptodate(page);
+ unlock_page(page);
+ /*
+ * Make sure the mft record is written out to disk. We could use
+ * ilookup5() to check if an inode is in icache and so on but this is
+ * unnecessary as ntfs_writepage() will write the dirty record anyway.
+ */
+ mark_ntfs_record_dirty(page, ofs);
+ ntfs_unmap_page(page);
+ ntfs_debug("Done.");
+ return 0;
+}
+
+/**
+ * ntfs_mft_record_alloc - allocate an mft record on an ntfs volume
+ * @vol: [IN] volume on which to allocate the mft record
+ * @mode: [IN] mode if want a file or directory, i.e. base inode or 0
+ * @base_ni: [IN] open base inode if allocating an extent mft record or NULL
+ * @mrec: [OUT] on successful return this is the mapped mft record
+ *
+ * Allocate an mft record in $MFT/$DATA of an open ntfs volume @vol.
+ *
+ * If @base_ni is NULL make the mft record a base mft record, i.e. a file or
+ * direvctory inode, and allocate it at the default allocator position. In
+ * this case @mode is the file mode as given to us by the caller. We in
+ * particular use @mode to distinguish whether a file or a directory is being
+ * created (S_IFDIR(mode) and S_IFREG(mode), respectively).
+ *
+ * If @base_ni is not NULL make the allocated mft record an extent record,
+ * allocate it starting at the mft record after the base mft record and attach
+ * the allocated and opened ntfs inode to the base inode @base_ni. In this
+ * case @mode must be 0 as it is meaningless for extent inodes.
+ *
+ * You need to check the return value with IS_ERR(). If false, the function
+ * was successful and the return value is the now opened ntfs inode of the
+ * allocated mft record. *@mrec is then set to the allocated, mapped, pinned,
+ * and locked mft record. If IS_ERR() is true, the function failed and the
+ * error code is obtained from PTR_ERR(return value). *@mrec is undefined in
+ * this case.
+ *
+ * Allocation strategy:
+ *
+ * To find a free mft record, we scan the mft bitmap for a zero bit. To
+ * optimize this we start scanning at the place specified by @base_ni or if
+ * @base_ni is NULL we start where we last stopped and we perform wrap around
+ * when we reach the end. Note, we do not try to allocate mft records below
+ * number 24 because numbers 0 to 15 are the defined system files anyway and 16
+ * to 24 are special in that they are used for storing extension mft records
+ * for the $DATA attribute of $MFT. This is required to avoid the possibility
+ * of creating a runlist with a circular dependency which once written to disk
+ * can never be read in again. Windows will only use records 16 to 24 for
+ * normal files if the volume is completely out of space. We never use them
+ * which means that when the volume is really out of space we cannot create any
+ * more files while Windows can still create up to 8 small files. We can start
+ * doing this at some later time, it does not matter much for now.
+ *
+ * When scanning the mft bitmap, we only search up to the last allocated mft
+ * record. If there are no free records left in the range 24 to number of
+ * allocated mft records, then we extend the $MFT/$DATA attribute in order to
+ * create free mft records. We extend the allocated size of $MFT/$DATA by 16
+ * records at a time or one cluster, if cluster size is above 16kiB. If there
+ * is not sufficient space to do this, we try to extend by a single mft record
+ * or one cluster, if cluster size is above the mft record size.
+ *
+ * No matter how many mft records we allocate, we initialize only the first
+ * allocated mft record, incrementing mft data size and initialized size
+ * accordingly, open an ntfs_inode for it and return it to the caller, unless
+ * there are less than 24 mft records, in which case we allocate and initialize
+ * mft records until we reach record 24 which we consider as the first free mft
+ * record for use by normal files.
+ *
+ * If during any stage we overflow the initialized data in the mft bitmap, we
+ * extend the initialized size (and data size) by 8 bytes, allocating another
+ * cluster if required. The bitmap data size has to be at least equal to the
+ * number of mft records in the mft, but it can be bigger, in which case the
+ * superflous bits are padded with zeroes.
+ *
+ * Thus, when we return successfully (IS_ERR() is false), we will have:
+ * - initialized / extended the mft bitmap if necessary,
+ * - initialized / extended the mft data if necessary,
+ * - set the bit corresponding to the mft record being allocated in the
+ * mft bitmap,
+ * - opened an ntfs_inode for the allocated mft record, and we will have
+ * - returned the ntfs_inode as well as the allocated mapped, pinned, and
+ * locked mft record.
+ *
+ * On error, the volume will be left in a consistent state and no record will
+ * be allocated. If rolling back a partial operation fails, we may leave some
+ * inconsistent metadata in which case we set NVolErrors() so the volume is
+ * left dirty when unmounted.
+ *
+ * Note, this function cannot make use of most of the normal functions, like
+ * for example for attribute resizing, etc, because when the run list overflows
+ * the base mft record and an attribute list is used, it is very important that
+ * the extension mft records used to store the $DATA attribute of $MFT can be
+ * reached without having to read the information contained inside them, as
+ * this would make it impossible to find them in the first place after the
+ * volume is unmounted. $MFT/$BITMAP probably does not need to follow this
+ * rule because the bitmap is not essential for finding the mft records, but on
+ * the other hand, handling the bitmap in this special way would make life
+ * easier because otherwise there might be circular invocations of functions
+ * when reading the bitmap.
+ */
+ntfs_inode *ntfs_mft_record_alloc(ntfs_volume *vol, const int mode,
+ ntfs_inode *base_ni, MFT_RECORD **mrec)
+{
+ s64 ll, bit, old_data_initialized, old_data_size;
+ struct inode *vi;
+ struct page *page;
+ ntfs_inode *mft_ni, *mftbmp_ni, *ni;
+ ntfs_attr_search_ctx *ctx;
+ MFT_RECORD *m;
+ ATTR_RECORD *a;
+ pgoff_t index;
+ unsigned int ofs;
+ int err;
+ le16 seq_no, usn;
+ BOOL record_formatted = FALSE;
+
+ if (base_ni) {
+ ntfs_debug("Entering (allocating an extent mft record for "
+ "base mft record 0x%llx).",
+ (long long)base_ni->mft_no);
+ /* @mode and @base_ni are mutually exclusive. */
+ BUG_ON(mode);
+ } else
+ ntfs_debug("Entering (allocating a base mft record).");
+ if (mode) {
+ /* @mode and @base_ni are mutually exclusive. */
+ BUG_ON(base_ni);
+ /* We only support creation of normal files and directories. */
+ if (!S_ISREG(mode) && !S_ISDIR(mode))
+ return ERR_PTR(-EOPNOTSUPP);
+ }
+ BUG_ON(!mrec);
+ mft_ni = NTFS_I(vol->mft_ino);
+ mftbmp_ni = NTFS_I(vol->mftbmp_ino);
+ down_write(&vol->mftbmp_lock);
+ bit = ntfs_mft_bitmap_find_and_alloc_free_rec_nolock(vol, base_ni);
+ if (bit >= 0) {
+ ntfs_debug("Found and allocated free record (#1), bit 0x%llx.",
+ (long long)bit);
+ goto have_alloc_rec;
+ }
+ if (bit != -ENOSPC) {
+ up_write(&vol->mftbmp_lock);
+ return ERR_PTR(bit);
+ }
+ /*
+ * No free mft records left. If the mft bitmap already covers more
+ * than the currently used mft records, the next records are all free,
+ * so we can simply allocate the first unused mft record.
+ * Note: We also have to make sure that the mft bitmap at least covers
+ * the first 24 mft records as they are special and whilst they may not
+ * be in use, we do not allocate from them.
+ */
+ ll = mft_ni->initialized_size >> vol->mft_record_size_bits;
+ if (mftbmp_ni->initialized_size << 3 > ll &&
+ mftbmp_ni->initialized_size > 3) {
+ bit = ll;
+ if (bit < 24)
+ bit = 24;
+ if (unlikely(bit >= (1ll << 32)))
+ goto max_err_out;
+ ntfs_debug("Found free record (#2), bit 0x%llx.",
+ (long long)bit);
+ goto found_free_rec;
+ }
+ /*
+ * The mft bitmap needs to be expanded until it covers the first unused
+ * mft record that we can allocate.
+ * Note: The smallest mft record we allocate is mft record 24.
+ */
+ bit = mftbmp_ni->initialized_size << 3;
+ if (unlikely(bit >= (1ll << 32)))
+ goto max_err_out;
+ ntfs_debug("Status of mftbmp before extension: allocated_size 0x%llx, "
+ "data_size 0x%llx, initialized_size 0x%llx.",
+ (long long)mftbmp_ni->allocated_size,
+ (long long)vol->mftbmp_ino->i_size,
+ (long long)mftbmp_ni->initialized_size);
+ if (mftbmp_ni->initialized_size + 8 > mftbmp_ni->allocated_size) {
+ /* Need to extend bitmap by one more cluster. */
+ ntfs_debug("mftbmp: initialized_size + 8 > allocated_size.");
+ err = ntfs_mft_bitmap_extend_allocation_nolock(vol);
+ if (unlikely(err)) {
+ up_write(&vol->mftbmp_lock);
+ goto err_out;
+ }
+ ntfs_debug("Status of mftbmp after allocation extension: "
+ "allocated_size 0x%llx, data_size 0x%llx, "
+ "initialized_size 0x%llx.",
+ (long long)mftbmp_ni->allocated_size,
+ (long long)vol->mftbmp_ino->i_size,
+ (long long)mftbmp_ni->initialized_size);
+ }
+ /*
+ * We now have sufficient allocated space, extend the initialized_size
+ * as well as the data_size if necessary and fill the new space with
+ * zeroes.
+ */
+ err = ntfs_mft_bitmap_extend_initialized_nolock(vol);
+ if (unlikely(err)) {
+ up_write(&vol->mftbmp_lock);
+ goto err_out;
+ }
+ ntfs_debug("Status of mftbmp after initialized extention: "
+ "allocated_size 0x%llx, data_size 0x%llx, "
+ "initialized_size 0x%llx.",
+ (long long)mftbmp_ni->allocated_size,
+ (long long)vol->mftbmp_ino->i_size,
+ (long long)mftbmp_ni->initialized_size);
+ ntfs_debug("Found free record (#3), bit 0x%llx.", (long long)bit);
+found_free_rec:
+ /* @bit is the found free mft record, allocate it in the mft bitmap. */
+ ntfs_debug("At found_free_rec.");
+ err = ntfs_bitmap_set_bit(vol->mftbmp_ino, bit);
+ if (unlikely(err)) {
+ ntfs_error(vol->sb, "Failed to allocate bit in mft bitmap.");
+ up_write(&vol->mftbmp_lock);
+ goto err_out;
+ }
+ ntfs_debug("Set bit 0x%llx in mft bitmap.", (long long)bit);
+have_alloc_rec:
+ /*
+ * The mft bitmap is now uptodate. Deal with mft data attribute now.
+ * Note, we keep hold of the mft bitmap lock for writing until all
+ * modifications to the mft data attribute are complete, too, as they
+ * will impact decisions for mft bitmap and mft record allocation done
+ * by a parallel allocation and if the lock is not maintained a
+ * parallel allocation could allocate the same mft record as this one.
+ */
+ ll = (bit + 1) << vol->mft_record_size_bits;
+ if (ll <= mft_ni->initialized_size) {
+ ntfs_debug("Allocated mft record already initialized.");
+ goto mft_rec_already_initialized;
+ }
+ ntfs_debug("Initializing allocated mft record.");
+ /*
+ * The mft record is outside the initialized data. Extend the mft data
+ * attribute until it covers the allocated record. The loop is only
+ * actually traversed more than once when a freshly formatted volume is
+ * first written to so it optimizes away nicely in the common case.
+ */
+ ntfs_debug("Status of mft data before extension: "
+ "allocated_size 0x%llx, data_size 0x%llx, "
+ "initialized_size 0x%llx.",
+ (long long)mft_ni->allocated_size,
+ (long long)vol->mft_ino->i_size,
+ (long long)mft_ni->initialized_size);
+ while (ll > mft_ni->allocated_size) {
+ err = ntfs_mft_data_extend_allocation_nolock(vol);
+ if (unlikely(err)) {
+ ntfs_error(vol->sb, "Failed to extend mft data "
+ "allocation.");
+ goto undo_mftbmp_alloc_nolock;
+ }
+ ntfs_debug("Status of mft data after allocation extension: "
+ "allocated_size 0x%llx, data_size 0x%llx, "
+ "initialized_size 0x%llx.",
+ (long long)mft_ni->allocated_size,
+ (long long)vol->mft_ino->i_size,
+ (long long)mft_ni->initialized_size);
+ }
+ /*
+ * Extend mft data initialized size (and data size of course) to reach
+ * the allocated mft record, formatting the mft records allong the way.
+ * Note: We only modify the ntfs_inode structure as that is all that is
+ * needed by ntfs_mft_record_format(). We will update the attribute
+ * record itself in one fell swoop later on.
+ */
+ old_data_initialized = mft_ni->initialized_size;
+ old_data_size = vol->mft_ino->i_size;
+ while (ll > mft_ni->initialized_size) {
+ s64 new_initialized_size, mft_no;
+
+ new_initialized_size = mft_ni->initialized_size +
+ vol->mft_record_size;
+ mft_no = mft_ni->initialized_size >> vol->mft_record_size_bits;
+ if (new_initialized_size > vol->mft_ino->i_size)
+ vol->mft_ino->i_size = new_initialized_size;
+ ntfs_debug("Initializing mft record 0x%llx.",
+ (long long)mft_no);
+ err = ntfs_mft_record_format(vol, mft_no);
+ if (unlikely(err)) {
+ ntfs_error(vol->sb, "Failed to format mft record.");
+ goto undo_data_init;
+ }
+ mft_ni->initialized_size = new_initialized_size;
+ }
+ record_formatted = TRUE;
+ /* Update the mft data attribute record to reflect the new sizes. */
+ m = map_mft_record(mft_ni);
+ if (IS_ERR(m)) {
+ ntfs_error(vol->sb, "Failed to map mft record.");
+ err = PTR_ERR(m);
+ goto undo_data_init;
+ }
+ ctx = ntfs_attr_get_search_ctx(mft_ni, m);
+ if (unlikely(!ctx)) {
+ ntfs_error(vol->sb, "Failed to get search context.");
+ err = -ENOMEM;
+ unmap_mft_record(mft_ni);
+ goto undo_data_init;
+ }
+ err = ntfs_attr_lookup(mft_ni->type, mft_ni->name, mft_ni->name_len,
+ CASE_SENSITIVE, 0, NULL, 0, ctx);
+ if (unlikely(err)) {
+ ntfs_error(vol->sb, "Failed to find first attribute extent of "
+ "mft data attribute.");
+ ntfs_attr_put_search_ctx(ctx);
+ unmap_mft_record(mft_ni);
+ goto undo_data_init;
+ }
+ a = ctx->attr;
+ a->data.non_resident.initialized_size =
+ cpu_to_sle64(mft_ni->initialized_size);
+ a->data.non_resident.data_size = cpu_to_sle64(vol->mft_ino->i_size);
+ /* Ensure the changes make it to disk. */
+ flush_dcache_mft_record_page(ctx->ntfs_ino);
+ mark_mft_record_dirty(ctx->ntfs_ino);
+ ntfs_attr_put_search_ctx(ctx);
+ unmap_mft_record(mft_ni);
+ ntfs_debug("Status of mft data after mft record initialization: "
+ "allocated_size 0x%llx, data_size 0x%llx, "
+ "initialized_size 0x%llx.",
+ (long long)mft_ni->allocated_size,
+ (long long)vol->mft_ino->i_size,
+ (long long)mft_ni->initialized_size);
+ BUG_ON(vol->mft_ino->i_size > mft_ni->allocated_size);
+ BUG_ON(mft_ni->initialized_size > vol->mft_ino->i_size);
+mft_rec_already_initialized:
+ /*
+ * We can finally drop the mft bitmap lock as the mft data attribute
+ * has been fully updated. The only disparity left is that the
+ * allocated mft record still needs to be marked as in use to match the
+ * set bit in the mft bitmap but this is actually not a problem since
+ * this mft record is not referenced from anywhere yet and the fact
+ * that it is allocated in the mft bitmap means that no-one will try to
+ * allocate it either.
+ */
+ up_write(&vol->mftbmp_lock);
+ /*
+ * We now have allocated and initialized the mft record. Calculate the
+ * index of and the offset within the page cache page the record is in.
+ */
+ index = bit << vol->mft_record_size_bits >> PAGE_CACHE_SHIFT;
+ ofs = (bit << vol->mft_record_size_bits) & ~PAGE_CACHE_MASK;
+ /* Read, map, and pin the page containing the mft record. */
+ page = ntfs_map_page(vol->mft_ino->i_mapping, index);
+ if (unlikely(IS_ERR(page))) {
+ ntfs_error(vol->sb, "Failed to map page containing allocated "
+ "mft record 0x%llx.", (long long)bit);
+ err = PTR_ERR(page);
+ goto undo_mftbmp_alloc;
+ }
+ lock_page(page);
+ BUG_ON(!PageUptodate(page));
+ ClearPageUptodate(page);
+ m = (MFT_RECORD*)((u8*)page_address(page) + ofs);
+ /* If we just formatted the mft record no need to do it again. */
+ if (!record_formatted) {
+ /* Sanity check that the mft record is really not in use. */
+ if (ntfs_is_file_record(m->magic) &&
+ (m->flags & MFT_RECORD_IN_USE)) {
+ ntfs_error(vol->sb, "Mft record 0x%llx was marked "
+ "free in mft bitmap but is marked "
+ "used itself. Corrupt filesystem. "
+ "Unmount and run chkdsk.",
+ (long long)bit);
+ err = -EIO;
+ SetPageUptodate(page);
+ unlock_page(page);
+ ntfs_unmap_page(page);
+ NVolSetErrors(vol);
+ goto undo_mftbmp_alloc;
+ }
+ /*
+ * We need to (re-)format the mft record, preserving the
+ * sequence number if it is not zero as well as the update
+ * sequence number if it is not zero or -1 (0xffff). This
+ * means we do not need to care whether or not something went
+ * wrong with the previous mft record.
+ */
+ seq_no = m->sequence_number;
+ usn = *(le16*)((u8*)m + le16_to_cpu(m->usa_ofs));
+ err = ntfs_mft_record_layout(vol, bit, m);
+ if (unlikely(err)) {
+ ntfs_error(vol->sb, "Failed to layout allocated mft "
+ "record 0x%llx.", (long long)bit);
+ SetPageUptodate(page);
+ unlock_page(page);
+ ntfs_unmap_page(page);
+ goto undo_mftbmp_alloc;
+ }
+ if (seq_no)
+ m->sequence_number = seq_no;
+ if (usn && le16_to_cpu(usn) != 0xffff)
+ *(le16*)((u8*)m + le16_to_cpu(m->usa_ofs)) = usn;
+ }
+ /* Set the mft record itself in use. */
+ m->flags |= MFT_RECORD_IN_USE;
+ if (S_ISDIR(mode))
+ m->flags |= MFT_RECORD_IS_DIRECTORY;
+ flush_dcache_page(page);
+ SetPageUptodate(page);
+ if (base_ni) {
+ /*
+ * Setup the base mft record in the extent mft record. This
+ * completes initialization of the allocated extent mft record
+ * and we can simply use it with map_extent_mft_record().
+ */
+ m->base_mft_record = MK_LE_MREF(base_ni->mft_no,
+ base_ni->seq_no);
+ /*
+ * Allocate an extent inode structure for the new mft record,
+ * attach it to the base inode @base_ni and map, pin, and lock
+ * its, i.e. the allocated, mft record.
+ */
+ m = map_extent_mft_record(base_ni, bit, &ni);
+ if (IS_ERR(m)) {
+ ntfs_error(vol->sb, "Failed to map allocated extent "
+ "mft record 0x%llx.", (long long)bit);
+ err = PTR_ERR(m);
+ /* Set the mft record itself not in use. */
+ m->flags &= cpu_to_le16(
+ ~le16_to_cpu(MFT_RECORD_IN_USE));
+ flush_dcache_page(page);
+ /* Make sure the mft record is written out to disk. */
+ mark_ntfs_record_dirty(page, ofs);
+ unlock_page(page);
+ ntfs_unmap_page(page);
+ goto undo_mftbmp_alloc;
+ }
+ /*
+ * Make sure the allocated mft record is written out to disk.
+ * No need to set the inode dirty because the caller is going
+ * to do that anyway after finishing with the new extent mft
+ * record (e.g. at a minimum a new attribute will be added to
+ * the mft record.
+ */
+ mark_ntfs_record_dirty(page, ofs);
+ unlock_page(page);
+ /*
+ * Need to unmap the page since map_extent_mft_record() mapped
+ * it as well so we have it mapped twice at the moment.
+ */
+ ntfs_unmap_page(page);
+ } else {
+ /*
+ * Allocate a new VFS inode and set it up. NOTE: @vi->i_nlink
+ * is set to 1 but the mft record->link_count is 0. The caller
+ * needs to bear this in mind.
+ */
+ vi = new_inode(vol->sb);
+ if (unlikely(!vi)) {
+ err = -ENOMEM;
+ /* Set the mft record itself not in use. */
+ m->flags &= cpu_to_le16(
+ ~le16_to_cpu(MFT_RECORD_IN_USE));
+ flush_dcache_page(page);
+ /* Make sure the mft record is written out to disk. */
+ mark_ntfs_record_dirty(page, ofs);
+ unlock_page(page);
+ ntfs_unmap_page(page);
+ goto undo_mftbmp_alloc;
+ }
+ vi->i_ino = bit;
+ /*
+ * This is the optimal IO size (for stat), not the fs block
+ * size.
+ */
+ vi->i_blksize = PAGE_CACHE_SIZE;
+ /*
+ * This is for checking whether an inode has changed w.r.t. a
+ * file so that the file can be updated if necessary (compare
+ * with f_version).
+ */
+ vi->i_version = 1;
+
+ /* The owner and group come from the ntfs volume. */
+ vi->i_uid = vol->uid;
+ vi->i_gid = vol->gid;
+
+ /* Initialize the ntfs specific part of @vi. */
+ ntfs_init_big_inode(vi);
+ ni = NTFS_I(vi);
+ /*
+ * Set the appropriate mode, attribute type, and name. For
+ * directories, also setup the index values to the defaults.
+ */
+ if (S_ISDIR(mode)) {
+ vi->i_mode = S_IFDIR | S_IRWXUGO;
+ vi->i_mode &= ~vol->dmask;
+
+ NInoSetMstProtected(ni);
+ ni->type = AT_INDEX_ALLOCATION;
+ ni->name = I30;
+ ni->name_len = 4;
+
+ ni->itype.index.block_size = 4096;
+ ni->itype.index.block_size_bits = generic_ffs(4096) - 1;
+ ni->itype.index.collation_rule = COLLATION_FILE_NAME;
+ if (vol->cluster_size <= ni->itype.index.block_size) {
+ ni->itype.index.vcn_size = vol->cluster_size;
+ ni->itype.index.vcn_size_bits =
+ vol->cluster_size_bits;
+ } else {
+ ni->itype.index.vcn_size = vol->sector_size;
+ ni->itype.index.vcn_size_bits =
+ vol->sector_size_bits;
+ }
+ } else {
+ vi->i_mode = S_IFREG | S_IRWXUGO;
+ vi->i_mode &= ~vol->fmask;
+
+ ni->type = AT_DATA;
+ ni->name = NULL;
+ ni->name_len = 0;
+ }
+ if (IS_RDONLY(vi))
+ vi->i_mode &= ~S_IWUGO;
+
+ /* Set the inode times to the current time. */
+ vi->i_atime = vi->i_mtime = vi->i_ctime = current_kernel_time();
+ /*
+ * Set the file size to 0, the ntfs inode sizes are set to 0 by
+ * the call to ntfs_init_big_inode() below.
+ */
+ vi->i_size = 0;
+ vi->i_blocks = 0;
+
+ /* Set the sequence number. */
+ vi->i_generation = ni->seq_no = le16_to_cpu(m->sequence_number);
+ /*
+ * Manually map, pin, and lock the mft record as we already
+ * have its page mapped and it is very easy to do.
+ */
+ atomic_inc(&ni->count);
+ down(&ni->mrec_lock);
+ ni->page = page;
+ ni->page_ofs = ofs;
+ /*
+ * Make sure the allocated mft record is written out to disk.
+ * NOTE: We do not set the ntfs inode dirty because this would
+ * fail in ntfs_write_inode() because the inode does not have a
+ * standard information attribute yet. Also, there is no need
+ * to set the inode dirty because the caller is going to do
+ * that anyway after finishing with the new mft record (e.g. at
+ * a minimum some new attributes will be added to the mft
+ * record.
+ */
+ mark_ntfs_record_dirty(page, ofs);
+ unlock_page(page);
+
+ /* Add the inode to the inode hash for the superblock. */
+ insert_inode_hash(vi);
+
+ /* Update the default mft allocation position. */
+ vol->mft_data_pos = bit + 1;
+ }
+ /*
+ * Return the opened, allocated inode of the allocated mft record as
+ * well as the mapped, pinned, and locked mft record.
+ */
+ ntfs_debug("Returning opened, allocated %sinode 0x%llx.",
+ base_ni ? "extent " : "", (long long)bit);
+ *mrec = m;
+ return ni;
+undo_data_init:
+ mft_ni->initialized_size = old_data_initialized;
+ vol->mft_ino->i_size = old_data_size;
+ goto undo_mftbmp_alloc_nolock;
+undo_mftbmp_alloc:
+ down_write(&vol->mftbmp_lock);
+undo_mftbmp_alloc_nolock:
+ if (ntfs_bitmap_clear_bit(vol->mftbmp_ino, bit)) {
+ ntfs_error(vol->sb, "Failed to clear bit in mft bitmap.%s", es);
+ NVolSetErrors(vol);
+ }
+ up_write(&vol->mftbmp_lock);
+err_out:
+ return ERR_PTR(err);
+max_err_out:
+ ntfs_warning(vol->sb, "Cannot allocate mft record because the maximum "
+ "number of inodes (2^32) has already been reached.");
+ up_write(&vol->mftbmp_lock);
+ return ERR_PTR(-ENOSPC);
+}
+
+/**
* ntfs_extent_mft_record_free - free an extent mft record on an ntfs volume
* @ni: ntfs inode of the mapped extent mft record to free
* @m: mapped extent mft record of the ntfs inode @ni
diff -Nru a/fs/ntfs/mft.h b/fs/ntfs/mft.h
--- a/fs/ntfs/mft.h 2004-10-19 10:15:13 +01:00
+++ b/fs/ntfs/mft.h 2004-10-19 10:15:13 +01:00
@@ -118,6 +118,8 @@
const unsigned long mft_no, const MFT_RECORD *m,
ntfs_inode **locked_ni);
+extern ntfs_inode *ntfs_mft_record_alloc(ntfs_volume *vol, const int mode,
+ ntfs_inode *base_ni, MFT_RECORD **mrec);
extern int ntfs_extent_mft_record_free(ntfs_inode *ni, MFT_RECORD *m);
#endif /* NTFS_RW */
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