diff options
Diffstat (limited to 'fs/ntfs/aops.c')
| -rw-r--r-- | fs/ntfs/aops.c | 1744 |
1 files changed, 0 insertions, 1744 deletions
diff --git a/fs/ntfs/aops.c b/fs/ntfs/aops.c deleted file mode 100644 index 2d01517a2d..0000000000 --- a/fs/ntfs/aops.c +++ /dev/null @@ -1,1744 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* - * aops.c - NTFS kernel address space operations and page cache handling. - * - * Copyright (c) 2001-2014 Anton Altaparmakov and Tuxera Inc. - * Copyright (c) 2002 Richard Russon - */ - -#include <linux/errno.h> -#include <linux/fs.h> -#include <linux/gfp.h> -#include <linux/mm.h> -#include <linux/pagemap.h> -#include <linux/swap.h> -#include <linux/buffer_head.h> -#include <linux/writeback.h> -#include <linux/bit_spinlock.h> -#include <linux/bio.h> - -#include "aops.h" -#include "attrib.h" -#include "debug.h" -#include "inode.h" -#include "mft.h" -#include "runlist.h" -#include "types.h" -#include "ntfs.h" - -/** - * ntfs_end_buffer_async_read - async io completion for reading attributes - * @bh: buffer head on which io is completed - * @uptodate: whether @bh is now uptodate or not - * - * Asynchronous I/O completion handler for reading pages belonging to the - * attribute address space of an inode. The inodes can either be files or - * directories or they can be fake inodes describing some attribute. - * - * If NInoMstProtected(), perform the post read mst fixups when all IO on the - * page has been completed and mark the page uptodate or set the error bit on - * the page. To determine the size of the records that need fixing up, we - * cheat a little bit by setting the index_block_size in ntfs_inode to the ntfs - * record size, and index_block_size_bits, to the log(base 2) of the ntfs - * record size. - */ -static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate) -{ - unsigned long flags; - struct buffer_head *first, *tmp; - struct page *page; - struct inode *vi; - ntfs_inode *ni; - int page_uptodate = 1; - - page = bh->b_page; - vi = page->mapping->host; - ni = NTFS_I(vi); - - if (likely(uptodate)) { - loff_t i_size; - s64 file_ofs, init_size; - - set_buffer_uptodate(bh); - - file_ofs = ((s64)page->index << PAGE_SHIFT) + - bh_offset(bh); - read_lock_irqsave(&ni->size_lock, flags); - init_size = ni->initialized_size; - i_size = i_size_read(vi); - read_unlock_irqrestore(&ni->size_lock, flags); - if (unlikely(init_size > i_size)) { - /* Race with shrinking truncate. */ - init_size = i_size; - } - /* Check for the current buffer head overflowing. */ - if (unlikely(file_ofs + bh->b_size > init_size)) { - int ofs; - void *kaddr; - - ofs = 0; - if (file_ofs < init_size) - ofs = init_size - file_ofs; - kaddr = kmap_atomic(page); - memset(kaddr + bh_offset(bh) + ofs, 0, - bh->b_size - ofs); - flush_dcache_page(page); - kunmap_atomic(kaddr); - } - } else { - clear_buffer_uptodate(bh); - SetPageError(page); - ntfs_error(ni->vol->sb, "Buffer I/O error, logical block " - "0x%llx.", (unsigned long long)bh->b_blocknr); - } - first = page_buffers(page); - spin_lock_irqsave(&first->b_uptodate_lock, flags); - clear_buffer_async_read(bh); - unlock_buffer(bh); - tmp = bh; - do { - if (!buffer_uptodate(tmp)) - page_uptodate = 0; - if (buffer_async_read(tmp)) { - if (likely(buffer_locked(tmp))) - goto still_busy; - /* Async buffers must be locked. */ - BUG(); - } - tmp = tmp->b_this_page; - } while (tmp != bh); - spin_unlock_irqrestore(&first->b_uptodate_lock, flags); - /* - * If none of the buffers had errors then we can set the page uptodate, - * but we first have to perform the post read mst fixups, if the - * attribute is mst protected, i.e. if NInoMstProteced(ni) is true. - * Note we ignore fixup errors as those are detected when - * map_mft_record() is called which gives us per record granularity - * rather than per page granularity. - */ - if (!NInoMstProtected(ni)) { - if (likely(page_uptodate && !PageError(page))) - SetPageUptodate(page); - } else { - u8 *kaddr; - unsigned int i, recs; - u32 rec_size; - - rec_size = ni->itype.index.block_size; - recs = PAGE_SIZE / rec_size; - /* Should have been verified before we got here... */ - BUG_ON(!recs); - kaddr = kmap_atomic(page); - for (i = 0; i < recs; i++) - post_read_mst_fixup((NTFS_RECORD*)(kaddr + - i * rec_size), rec_size); - kunmap_atomic(kaddr); - flush_dcache_page(page); - if (likely(page_uptodate && !PageError(page))) - SetPageUptodate(page); - } - unlock_page(page); - return; -still_busy: - spin_unlock_irqrestore(&first->b_uptodate_lock, flags); - return; -} - -/** - * ntfs_read_block - fill a @folio of an address space with data - * @folio: page cache folio to fill with data - * - * We read each buffer asynchronously and when all buffers are read in, our io - * completion handler ntfs_end_buffer_read_async(), if required, automatically - * applies the mst fixups to the folio before finally marking it uptodate and - * unlocking it. - * - * We only enforce allocated_size limit because i_size is checked for in - * generic_file_read(). - * - * Return 0 on success and -errno on error. - * - * Contains an adapted version of fs/buffer.c::block_read_full_folio(). - */ -static int ntfs_read_block(struct folio *folio) -{ - loff_t i_size; - VCN vcn; - LCN lcn; - s64 init_size; - struct inode *vi; - ntfs_inode *ni; - ntfs_volume *vol; - runlist_element *rl; - struct buffer_head *bh, *head, *arr[MAX_BUF_PER_PAGE]; - sector_t iblock, lblock, zblock; - unsigned long flags; - unsigned int blocksize, vcn_ofs; - int i, nr; - unsigned char blocksize_bits; - - vi = folio->mapping->host; - ni = NTFS_I(vi); - vol = ni->vol; - - /* $MFT/$DATA must have its complete runlist in memory at all times. */ - BUG_ON(!ni->runlist.rl && !ni->mft_no && !NInoAttr(ni)); - - blocksize = vol->sb->s_blocksize; - blocksize_bits = vol->sb->s_blocksize_bits; - - head = folio_buffers(folio); - if (!head) - head = create_empty_buffers(folio, blocksize, 0); - bh = head; - - /* - * We may be racing with truncate. To avoid some of the problems we - * now take a snapshot of the various sizes and use those for the whole - * of the function. In case of an extending truncate it just means we - * may leave some buffers unmapped which are now allocated. This is - * not a problem since these buffers will just get mapped when a write - * occurs. In case of a shrinking truncate, we will detect this later - * on due to the runlist being incomplete and if the folio is being - * fully truncated, truncate will throw it away as soon as we unlock - * it so no need to worry what we do with it. - */ - iblock = (s64)folio->index << (PAGE_SHIFT - blocksize_bits); - read_lock_irqsave(&ni->size_lock, flags); - lblock = (ni->allocated_size + blocksize - 1) >> blocksize_bits; - init_size = ni->initialized_size; - i_size = i_size_read(vi); - read_unlock_irqrestore(&ni->size_lock, flags); - if (unlikely(init_size > i_size)) { - /* Race with shrinking truncate. */ - init_size = i_size; - } - zblock = (init_size + blocksize - 1) >> blocksize_bits; - - /* Loop through all the buffers in the folio. */ - rl = NULL; - nr = i = 0; - do { - int err = 0; - - if (unlikely(buffer_uptodate(bh))) - continue; - if (unlikely(buffer_mapped(bh))) { - arr[nr++] = bh; - continue; - } - bh->b_bdev = vol->sb->s_bdev; - /* Is the block within the allowed limits? */ - if (iblock < lblock) { - bool is_retry = false; - - /* Convert iblock into corresponding vcn and offset. */ - vcn = (VCN)iblock << blocksize_bits >> - vol->cluster_size_bits; - vcn_ofs = ((VCN)iblock << blocksize_bits) & - vol->cluster_size_mask; - if (!rl) { -lock_retry_remap: - down_read(&ni->runlist.lock); - rl = ni->runlist.rl; - } - if (likely(rl != NULL)) { - /* Seek to element containing target vcn. */ - while (rl->length && rl[1].vcn <= vcn) - rl++; - lcn = ntfs_rl_vcn_to_lcn(rl, vcn); - } else - lcn = LCN_RL_NOT_MAPPED; - /* Successful remap. */ - if (lcn >= 0) { - /* Setup buffer head to correct block. */ - bh->b_blocknr = ((lcn << vol->cluster_size_bits) - + vcn_ofs) >> blocksize_bits; - set_buffer_mapped(bh); - /* Only read initialized data blocks. */ - if (iblock < zblock) { - arr[nr++] = bh; - continue; - } - /* Fully non-initialized data block, zero it. */ - goto handle_zblock; - } - /* It is a hole, need to zero it. */ - if (lcn == LCN_HOLE) - goto handle_hole; - /* If first try and runlist unmapped, map and retry. */ - if (!is_retry && lcn == LCN_RL_NOT_MAPPED) { - is_retry = true; - /* - * Attempt to map runlist, dropping lock for - * the duration. - */ - up_read(&ni->runlist.lock); - err = ntfs_map_runlist(ni, vcn); - if (likely(!err)) - goto lock_retry_remap; - rl = NULL; - } else if (!rl) - up_read(&ni->runlist.lock); - /* - * If buffer is outside the runlist, treat it as a - * hole. This can happen due to concurrent truncate - * for example. - */ - if (err == -ENOENT || lcn == LCN_ENOENT) { - err = 0; - goto handle_hole; - } - /* Hard error, zero out region. */ - if (!err) - err = -EIO; - bh->b_blocknr = -1; - folio_set_error(folio); - ntfs_error(vol->sb, "Failed to read from inode 0x%lx, " - "attribute type 0x%x, vcn 0x%llx, " - "offset 0x%x because its location on " - "disk could not be determined%s " - "(error code %i).", ni->mft_no, - ni->type, (unsigned long long)vcn, - vcn_ofs, is_retry ? " even after " - "retrying" : "", err); - } - /* - * Either iblock was outside lblock limits or - * ntfs_rl_vcn_to_lcn() returned error. Just zero that portion - * of the folio and set the buffer uptodate. - */ -handle_hole: - bh->b_blocknr = -1UL; - clear_buffer_mapped(bh); -handle_zblock: - folio_zero_range(folio, i * blocksize, blocksize); - if (likely(!err)) - set_buffer_uptodate(bh); - } while (i++, iblock++, (bh = bh->b_this_page) != head); - - /* Release the lock if we took it. */ - if (rl) - up_read(&ni->runlist.lock); - - /* Check we have at least one buffer ready for i/o. */ - if (nr) { - struct buffer_head *tbh; - - /* Lock the buffers. */ - for (i = 0; i < nr; i++) { - tbh = arr[i]; - lock_buffer(tbh); - tbh->b_end_io = ntfs_end_buffer_async_read; - set_buffer_async_read(tbh); - } - /* Finally, start i/o on the buffers. */ - for (i = 0; i < nr; i++) { - tbh = arr[i]; - if (likely(!buffer_uptodate(tbh))) - submit_bh(REQ_OP_READ, tbh); - else - ntfs_end_buffer_async_read(tbh, 1); - } - return 0; - } - /* No i/o was scheduled on any of the buffers. */ - if (likely(!folio_test_error(folio))) - folio_mark_uptodate(folio); - else /* Signal synchronous i/o error. */ - nr = -EIO; - folio_unlock(folio); - return nr; -} - -/** - * ntfs_read_folio - fill a @folio of a @file with data from the device - * @file: open file to which the folio @folio belongs or NULL - * @folio: page cache folio to fill with data - * - * For non-resident attributes, ntfs_read_folio() fills the @folio of the open - * file @file by calling the ntfs version of the generic block_read_full_folio() - * function, ntfs_read_block(), which in turn creates and reads in the buffers - * associated with the folio asynchronously. - * - * For resident attributes, OTOH, ntfs_read_folio() fills @folio by copying the - * data from the mft record (which at this stage is most likely in memory) and - * fills the remainder with zeroes. Thus, in this case, I/O is synchronous, as - * even if the mft record is not cached at this point in time, we need to wait - * for it to be read in before we can do the copy. - * - * Return 0 on success and -errno on error. - */ -static int ntfs_read_folio(struct file *file, struct folio *folio) -{ - struct page *page = &folio->page; - loff_t i_size; - struct inode *vi; - ntfs_inode *ni, *base_ni; - u8 *addr; - ntfs_attr_search_ctx *ctx; - MFT_RECORD *mrec; - unsigned long flags; - u32 attr_len; - int err = 0; - -retry_readpage: - BUG_ON(!PageLocked(page)); - vi = page->mapping->host; - i_size = i_size_read(vi); - /* Is the page fully outside i_size? (truncate in progress) */ - if (unlikely(page->index >= (i_size + PAGE_SIZE - 1) >> - PAGE_SHIFT)) { - zero_user(page, 0, PAGE_SIZE); - ntfs_debug("Read outside i_size - truncated?"); - goto done; - } - /* - * This can potentially happen because we clear PageUptodate() during - * ntfs_writepage() of MstProtected() attributes. - */ - if (PageUptodate(page)) { - unlock_page(page); - return 0; - } - ni = NTFS_I(vi); - /* - * Only $DATA attributes can be encrypted and only unnamed $DATA - * attributes can be compressed. Index root can have the flags set but - * this means to create compressed/encrypted files, not that the - * attribute is compressed/encrypted. Note we need to check for - * AT_INDEX_ALLOCATION since this is the type of both directory and - * index inodes. - */ - if (ni->type != AT_INDEX_ALLOCATION) { - /* If attribute is encrypted, deny access, just like NT4. */ - if (NInoEncrypted(ni)) { - BUG_ON(ni->type != AT_DATA); - err = -EACCES; - goto err_out; - } - /* Compressed data streams are handled in compress.c. */ - if (NInoNonResident(ni) && NInoCompressed(ni)) { - BUG_ON(ni->type != AT_DATA); - BUG_ON(ni->name_len); - return ntfs_read_compressed_block(page); - } - } - /* NInoNonResident() == NInoIndexAllocPresent() */ - if (NInoNonResident(ni)) { - /* Normal, non-resident data stream. */ - return ntfs_read_block(folio); - } - /* - * Attribute is resident, implying it is not compressed or encrypted. - * This also means the attribute is smaller than an mft record and - * hence smaller than a page, so can simply zero out any pages with - * index above 0. Note the attribute can actually be marked compressed - * but if it is resident the actual data is not compressed so we are - * ok to ignore the compressed flag here. - */ - if (unlikely(page->index > 0)) { - zero_user(page, 0, PAGE_SIZE); - goto done; - } - if (!NInoAttr(ni)) - base_ni = ni; - else - base_ni = ni->ext.base_ntfs_ino; - /* Map, pin, and lock the mft record. */ - mrec = map_mft_record(base_ni); - if (IS_ERR(mrec)) { - err = PTR_ERR(mrec); - goto err_out; - } - /* - * If a parallel write made the attribute non-resident, drop the mft - * record and retry the read_folio. - */ - if (unlikely(NInoNonResident(ni))) { - unmap_mft_record(base_ni); - goto retry_readpage; - } - ctx = ntfs_attr_get_search_ctx(base_ni, mrec); - if (unlikely(!ctx)) { - err = -ENOMEM; - goto unm_err_out; - } - err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len, - CASE_SENSITIVE, 0, NULL, 0, ctx); - if (unlikely(err)) - goto put_unm_err_out; - attr_len = le32_to_cpu(ctx->attr->data.resident.value_length); - read_lock_irqsave(&ni->size_lock, flags); - if (unlikely(attr_len > ni->initialized_size)) - attr_len = ni->initialized_size; - i_size = i_size_read(vi); - read_unlock_irqrestore(&ni->size_lock, flags); - if (unlikely(attr_len > i_size)) { - /* Race with shrinking truncate. */ - attr_len = i_size; - } - addr = kmap_atomic(page); - /* Copy the data to the page. */ - memcpy(addr, (u8*)ctx->attr + - le16_to_cpu(ctx->attr->data.resident.value_offset), - attr_len); - /* Zero the remainder of the page. */ - memset(addr + attr_len, 0, PAGE_SIZE - attr_len); - flush_dcache_page(page); - kunmap_atomic(addr); -put_unm_err_out: - ntfs_attr_put_search_ctx(ctx); -unm_err_out: - unmap_mft_record(base_ni); -done: - SetPageUptodate(page); -err_out: - unlock_page(page); - return err; -} - -#ifdef NTFS_RW - -/** - * ntfs_write_block - write a @folio to the backing store - * @folio: page cache folio to write out - * @wbc: writeback control structure - * - * This function is for writing folios belonging to non-resident, non-mst - * protected attributes to their backing store. - * - * For a folio with buffers, map and write the dirty buffers asynchronously - * under folio writeback. For a folio without buffers, create buffers for the - * folio, then proceed as above. - * - * If a folio doesn't have buffers the folio dirty state is definitive. If - * a folio does have buffers, the folio dirty state is just a hint, - * and the buffer dirty state is definitive. (A hint which has rules: - * dirty buffers against a clean folio is illegal. Other combinations are - * legal and need to be handled. In particular a dirty folio containing - * clean buffers for example.) - * - * Return 0 on success and -errno on error. - * - * Based on ntfs_read_block() and __block_write_full_folio(). - */ -static int ntfs_write_block(struct folio *folio, struct writeback_control *wbc) -{ - VCN vcn; - LCN lcn; - s64 initialized_size; - loff_t i_size; - sector_t block, dblock, iblock; - struct inode *vi; - ntfs_inode *ni; - ntfs_volume *vol; - runlist_element *rl; - struct buffer_head *bh, *head; - unsigned long flags; - unsigned int blocksize, vcn_ofs; - int err; - bool need_end_writeback; - unsigned char blocksize_bits; - - vi = folio->mapping->host; - ni = NTFS_I(vi); - vol = ni->vol; - - ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, page index " - "0x%lx.", ni->mft_no, ni->type, folio->index); - - BUG_ON(!NInoNonResident(ni)); - BUG_ON(NInoMstProtected(ni)); - blocksize = vol->sb->s_blocksize; - blocksize_bits = vol->sb->s_blocksize_bits; - head = folio_buffers(folio); - if (!head) { - BUG_ON(!folio_test_uptodate(folio)); - head = create_empty_buffers(folio, blocksize, - (1 << BH_Uptodate) | (1 << BH_Dirty)); - } - bh = head; - - /* NOTE: Different naming scheme to ntfs_read_block()! */ - - /* The first block in the folio. */ - block = (s64)folio->index << (PAGE_SHIFT - blocksize_bits); - - read_lock_irqsave(&ni->size_lock, flags); - i_size = i_size_read(vi); - initialized_size = ni->initialized_size; - read_unlock_irqrestore(&ni->size_lock, flags); - - /* The first out of bounds block for the data size. */ - dblock = (i_size + blocksize - 1) >> blocksize_bits; - - /* The last (fully or partially) initialized block. */ - iblock = initialized_size >> blocksize_bits; - - /* - * Be very careful. We have no exclusion from block_dirty_folio - * here, and the (potentially unmapped) buffers may become dirty at - * any time. If a buffer becomes dirty here after we've inspected it - * then we just miss that fact, and the folio stays dirty. - * - * Buffers outside i_size may be dirtied by block_dirty_folio; - * handle that here by just cleaning them. - */ - - /* - * Loop through all the buffers in the folio, mapping all the dirty - * buffers to disk addresses and handling any aliases from the - * underlying block device's mapping. - */ - rl = NULL; - err = 0; - do { - bool is_retry = false; - - if (unlikely(block >= dblock)) { - /* - * Mapped buffers outside i_size will occur, because - * this folio can be outside i_size when there is a - * truncate in progress. The contents of such buffers - * were zeroed by ntfs_writepage(). - * - * FIXME: What about the small race window where - * ntfs_writepage() has not done any clearing because - * the folio was within i_size but before we get here, - * vmtruncate() modifies i_size? - */ - clear_buffer_dirty(bh); - set_buffer_uptodate(bh); - continue; - } - - /* Clean buffers are not written out, so no need to map them. */ - if (!buffer_dirty(bh)) - continue; - - /* Make sure we have enough initialized size. */ - if (unlikely((block >= iblock) && - (initialized_size < i_size))) { - /* - * If this folio is fully outside initialized - * size, zero out all folios between the current - * initialized size and the current folio. Just - * use ntfs_read_folio() to do the zeroing - * transparently. - */ - if (block > iblock) { - // TODO: - // For each folio do: - // - read_cache_folio() - // Again for each folio do: - // - wait_on_folio_locked() - // - Check (folio_test_uptodate(folio) && - // !folio_test_error(folio)) - // Update initialized size in the attribute and - // in the inode. - // Again, for each folio do: - // block_dirty_folio(); - // folio_put() - // We don't need to wait on the writes. - // Update iblock. - } - /* - * The current folio straddles initialized size. Zero - * all non-uptodate buffers and set them uptodate (and - * dirty?). Note, there aren't any non-uptodate buffers - * if the folio is uptodate. - * FIXME: For an uptodate folio, the buffers may need to - * be written out because they were not initialized on - * disk before. - */ - if (!folio_test_uptodate(folio)) { - // TODO: - // Zero any non-uptodate buffers up to i_size. - // Set them uptodate and dirty. - } - // TODO: - // Update initialized size in the attribute and in the - // inode (up to i_size). - // Update iblock. - // FIXME: This is inefficient. Try to batch the two - // size changes to happen in one go. - ntfs_error(vol->sb, "Writing beyond initialized size " - "is not supported yet. Sorry."); - err = -EOPNOTSUPP; - break; - // Do NOT set_buffer_new() BUT DO clear buffer range - // outside write request range. - // set_buffer_uptodate() on complete buffers as well as - // set_buffer_dirty(). - } - - /* No need to map buffers that are already mapped. */ - if (buffer_mapped(bh)) - continue; - - /* Unmapped, dirty buffer. Need to map it. */ - bh->b_bdev = vol->sb->s_bdev; - - /* Convert block into corresponding vcn and offset. */ - vcn = (VCN)block << blocksize_bits; - vcn_ofs = vcn & vol->cluster_size_mask; - vcn >>= vol->cluster_size_bits; - if (!rl) { -lock_retry_remap: - down_read(&ni->runlist.lock); - rl = ni->runlist.rl; - } - if (likely(rl != NULL)) { - /* Seek to element containing target vcn. */ - while (rl->length && rl[1].vcn <= vcn) - rl++; - lcn = ntfs_rl_vcn_to_lcn(rl, vcn); - } else - lcn = LCN_RL_NOT_MAPPED; - /* Successful remap. */ - if (lcn >= 0) { - /* Setup buffer head to point to correct block. */ - bh->b_blocknr = ((lcn << vol->cluster_size_bits) + - vcn_ofs) >> blocksize_bits; - set_buffer_mapped(bh); - continue; - } - /* It is a hole, need to instantiate it. */ - if (lcn == LCN_HOLE) { - u8 *kaddr; - unsigned long *bpos, *bend; - - /* Check if the buffer is zero. */ - kaddr = kmap_local_folio(folio, bh_offset(bh)); - bpos = (unsigned long *)kaddr; - bend = (unsigned long *)(kaddr + blocksize); - do { - if (unlikely(*bpos)) - break; - } while (likely(++bpos < bend)); - kunmap_local(kaddr); - if (bpos == bend) { - /* - * Buffer is zero and sparse, no need to write - * it. - */ - bh->b_blocknr = -1; - clear_buffer_dirty(bh); - continue; - } - // TODO: Instantiate the hole. - // clear_buffer_new(bh); - // clean_bdev_bh_alias(bh); - ntfs_error(vol->sb, "Writing into sparse regions is " - "not supported yet. Sorry."); - err = -EOPNOTSUPP; - break; - } - /* If first try and runlist unmapped, map and retry. */ - if (!is_retry && lcn == LCN_RL_NOT_MAPPED) { - is_retry = true; - /* - * Attempt to map runlist, dropping lock for - * the duration. - */ - up_read(&ni->runlist.lock); - err = ntfs_map_runlist(ni, vcn); - if (likely(!err)) - goto lock_retry_remap; - rl = NULL; - } else if (!rl) - up_read(&ni->runlist.lock); - /* - * If buffer is outside the runlist, truncate has cut it out - * of the runlist. Just clean and clear the buffer and set it - * uptodate so it can get discarded by the VM. - */ - if (err == -ENOENT || lcn == LCN_ENOENT) { - bh->b_blocknr = -1; - clear_buffer_dirty(bh); - folio_zero_range(folio, bh_offset(bh), blocksize); - set_buffer_uptodate(bh); - err = 0; - continue; - } - /* Failed to map the buffer, even after retrying. */ - if (!err) - err = -EIO; - bh->b_blocknr = -1; - ntfs_error(vol->sb, "Failed to write to inode 0x%lx, " - "attribute type 0x%x, vcn 0x%llx, offset 0x%x " - "because its location on disk could not be " - "determined%s (error code %i).", ni->mft_no, - ni->type, (unsigned long long)vcn, - vcn_ofs, is_retry ? " even after " - "retrying" : "", err); - break; - } while (block++, (bh = bh->b_this_page) != head); - - /* Release the lock if we took it. */ - if (rl) - up_read(&ni->runlist.lock); - - /* For the error case, need to reset bh to the beginning. */ - bh = head; - - /* Just an optimization, so ->read_folio() is not called later. */ - if (unlikely(!folio_test_uptodate(folio))) { - int uptodate = 1; - do { - if (!buffer_uptodate(bh)) { - uptodate = 0; - bh = head; - break; - } - } while ((bh = bh->b_this_page) != head); - if (uptodate) - folio_mark_uptodate(folio); - } - - /* Setup all mapped, dirty buffers for async write i/o. */ - do { - if (buffer_mapped(bh) && buffer_dirty(bh)) { - lock_buffer(bh); - if (test_clear_buffer_dirty(bh)) { - BUG_ON(!buffer_uptodate(bh)); - mark_buffer_async_write(bh); - } else - unlock_buffer(bh); - } else if (unlikely(err)) { - /* - * For the error case. The buffer may have been set - * dirty during attachment to a dirty folio. - */ - if (err != -ENOMEM) - clear_buffer_dirty(bh); - } - } while ((bh = bh->b_this_page) != head); - - if (unlikely(err)) { - // TODO: Remove the -EOPNOTSUPP check later on... - if (unlikely(err == -EOPNOTSUPP)) - err = 0; - else if (err == -ENOMEM) { - ntfs_warning(vol->sb, "Error allocating memory. " - "Redirtying folio so we try again " - "later."); - /* - * Put the folio back on mapping->dirty_pages, but - * leave its buffer's dirty state as-is. - */ - folio_redirty_for_writepage(wbc, folio); - err = 0; - } else - folio_set_error(folio); - } - - BUG_ON(folio_test_writeback(folio)); - folio_start_writeback(folio); /* Keeps try_to_free_buffers() away. */ - - /* Submit the prepared buffers for i/o. */ - need_end_writeback = true; - do { - struct buffer_head *next = bh->b_this_page; - if (buffer_async_write(bh)) { - submit_bh(REQ_OP_WRITE, bh); - need_end_writeback = false; - } - bh = next; - } while (bh != head); - folio_unlock(folio); - - /* If no i/o was started, need to end writeback here. */ - if (unlikely(need_end_writeback)) - folio_end_writeback(folio); - - ntfs_debug("Done."); - return err; -} - -/** - * ntfs_write_mst_block - write a @page to the backing store - * @page: page cache page to write out - * @wbc: writeback control structure - * - * This function is for writing pages belonging to non-resident, mst protected - * attributes to their backing store. The only supported attributes are index - * allocation and $MFT/$DATA. Both directory inodes and index inodes are - * supported for the index allocation case. - * - * The page must remain locked for the duration of the write because we apply - * the mst fixups, write, and then undo the fixups, so if we were to unlock the - * page before undoing the fixups, any other user of the page will see the - * page contents as corrupt. - * - * We clear the page uptodate flag for the duration of the function to ensure - * exclusion for the $MFT/$DATA case against someone mapping an mft record we - * are about to apply the mst fixups to. - * - * Return 0 on success and -errno on error. - * - * Based on ntfs_write_block(), ntfs_mft_writepage(), and - * write_mft_record_nolock(). - */ -static int ntfs_write_mst_block(struct page *page, - struct writeback_control *wbc) -{ - sector_t block, dblock, rec_block; - struct inode *vi = page->mapping->host; - ntfs_inode *ni = NTFS_I(vi); - ntfs_volume *vol = ni->vol; - u8 *kaddr; - unsigned int rec_size = ni->itype.index.block_size; - ntfs_inode *locked_nis[PAGE_SIZE / NTFS_BLOCK_SIZE]; - struct buffer_head *bh, *head, *tbh, *rec_start_bh; - struct buffer_head *bhs[MAX_BUF_PER_PAGE]; - runlist_element *rl; - int i, nr_locked_nis, nr_recs, nr_bhs, max_bhs, bhs_per_rec, err, err2; - unsigned bh_size, rec_size_bits; - bool sync, is_mft, page_is_dirty, rec_is_dirty; - unsigned char bh_size_bits; - - if (WARN_ON(rec_size < NTFS_BLOCK_SIZE)) - return -EINVAL; - - ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, page index " - "0x%lx.", vi->i_ino, ni->type, page->index); - BUG_ON(!NInoNonResident(ni)); - BUG_ON(!NInoMstProtected(ni)); - is_mft = (S_ISREG(vi->i_mode) && !vi->i_ino); - /* - * NOTE: ntfs_write_mst_block() would be called for $MFTMirr if a page - * in its page cache were to be marked dirty. However this should - * never happen with the current driver and considering we do not - * handle this case here we do want to BUG(), at least for now. - */ - BUG_ON(!(is_mft || S_ISDIR(vi->i_mode) || - (NInoAttr(ni) && ni->type == AT_INDEX_ALLOCATION))); - bh_size = vol->sb->s_blocksize; - bh_size_bits = vol->sb->s_blocksize_bits; - max_bhs = PAGE_SIZE / bh_size; - BUG_ON(!max_bhs); - BUG_ON(max_bhs > MAX_BUF_PER_PAGE); - - /* Were we called for sync purposes? */ - sync = (wbc->sync_mode == WB_SYNC_ALL); - - /* Make sure we have mapped buffers. */ - bh = head = page_buffers(page); - BUG_ON(!bh); - - rec_size_bits = ni->itype.index.block_size_bits; - BUG_ON(!(PAGE_SIZE >> rec_size_bits)); - bhs_per_rec = rec_size >> bh_size_bits; - BUG_ON(!bhs_per_rec); - - /* The first block in the page. */ - rec_block = block = (sector_t)page->index << - (PAGE_SHIFT - bh_size_bits); - - /* The first out of bounds block for the data size. */ - dblock = (i_size_read(vi) + bh_size - 1) >> bh_size_bits; - - rl = NULL; - err = err2 = nr_bhs = nr_recs = nr_locked_nis = 0; - page_is_dirty = rec_is_dirty = false; - rec_start_bh = NULL; - do { - bool is_retry = false; - - if (likely(block < rec_block)) { - if (unlikely(block >= dblock)) { - clear_buffer_dirty(bh); - set_buffer_uptodate(bh); - continue; - } - /* - * This block is not the first one in the record. We - * ignore the buffer's dirty state because we could - * have raced with a parallel mark_ntfs_record_dirty(). - */ - if (!rec_is_dirty) - continue; - if (unlikely(err2)) { - if (err2 != -ENOMEM) - clear_buffer_dirty(bh); - continue; - } - } else /* if (block == rec_block) */ { - BUG_ON(block > rec_block); - /* This block is the first one in the record. */ - rec_block += bhs_per_rec; - err2 = 0; - if (unlikely(block >= dblock)) { - clear_buffer_dirty(bh); - continue; - } - if (!buffer_dirty(bh)) { - /* Clean records are not written out. */ - rec_is_dirty = false; - continue; - } - rec_is_dirty = true; - rec_start_bh = bh; - } - /* Need to map the buffer if it is not mapped already. */ - if (unlikely(!buffer_mapped(bh))) { - VCN vcn; - LCN lcn; - unsigned int vcn_ofs; - - bh->b_bdev = vol->sb->s_bdev; - /* Obtain the vcn and offset of the current block. */ - vcn = (VCN)block << bh_size_bits; - vcn_ofs = vcn & vol->cluster_size_mask; - vcn >>= vol->cluster_size_bits; - if (!rl) { -lock_retry_remap: - down_read(&ni->runlist.lock); - rl = ni->runlist.rl; - } - if (likely(rl != NULL)) { - /* Seek to element containing target vcn. */ - while (rl->length && rl[1].vcn <= vcn) - rl++; - lcn = ntfs_rl_vcn_to_lcn(rl, vcn); - } else - lcn = LCN_RL_NOT_MAPPED; - /* Successful remap. */ - if (likely(lcn >= 0)) { - /* Setup buffer head to correct block. */ - bh->b_blocknr = ((lcn << - vol->cluster_size_bits) + - vcn_ofs) >> bh_size_bits; - set_buffer_mapped(bh); - } else { - /* - * Remap failed. Retry to map the runlist once - * unless we are working on $MFT which always - * has the whole of its runlist in memory. - */ - if (!is_mft && !is_retry && - lcn == LCN_RL_NOT_MAPPED) { - is_retry = true; - /* - * Attempt to map runlist, dropping - * lock for the duration. - */ - up_read(&ni->runlist.lock); - err2 = ntfs_map_runlist(ni, vcn); - if (likely(!err2)) - goto lock_retry_remap; - if (err2 == -ENOMEM) - page_is_dirty = true; - lcn = err2; - } else { - err2 = -EIO; - if (!rl) - up_read(&ni->runlist.lock); - } - /* Hard error. Abort writing this record. */ - if (!err || err == -ENOMEM) - err = err2; - bh->b_blocknr = -1; - ntfs_error(vol->sb, "Cannot write ntfs record " - "0x%llx (inode 0x%lx, " - "attribute type 0x%x) because " - "its location on disk could " - "not be determined (error " - "code %lli).", - (long long)block << - bh_size_bits >> - vol->mft_record_size_bits, - ni->mft_no, ni->type, - (long long)lcn); - /* - * If this is not the first buffer, remove the - * buffers in this record from the list of - * buffers to write and clear their dirty bit - * if not error -ENOMEM. - */ - if (rec_start_bh != bh) { - while (bhs[--nr_bhs] != rec_start_bh) - ; - if (err2 != -ENOMEM) { - do { - clear_buffer_dirty( - rec_start_bh); - } while ((rec_start_bh = - rec_start_bh-> - b_this_page) != - bh); - } - } - continue; - } - } - BUG_ON(!buffer_uptodate(bh)); - BUG_ON(nr_bhs >= max_bhs); - bhs[nr_bhs++] = bh; - } while (block++, (bh = bh->b_this_page) != head); - if (unlikely(rl)) - up_read(&ni->runlist.lock); - /* If there were no dirty buffers, we are done. */ - if (!nr_bhs) - goto done; - /* Map the page so we can access its contents. */ - kaddr = kmap(page); - /* Clear the page uptodate flag whilst the mst fixups are applied. */ - BUG_ON(!PageUptodate(page)); - ClearPageUptodate(page); - for (i = 0; i < nr_bhs; i++) { - unsigned int ofs; - - /* Skip buffers which are not at the beginning of records. */ - if (i % bhs_per_rec) - continue; - tbh = bhs[i]; - ofs = bh_offset(tbh); - if (is_mft) { - ntfs_inode *tni; - unsigned long mft_no; - - /* Get the mft record number. */ - mft_no = (((s64)page->index << PAGE_SHIFT) + ofs) - >> rec_size_bits; - /* Check whether to write this mft record. */ - tni = NULL; - if (!ntfs_may_write_mft_record(vol, mft_no, - (MFT_RECORD*)(kaddr + ofs), &tni)) { - /* - * The record should not be written. This - * means we need to redirty the page before - * returning. - */ - page_is_dirty = true; - /* - * Remove the buffers in this mft record from - * the list of buffers to write. - */ - do { - bhs[i] = NULL; - } while (++i % bhs_per_rec); - continue; - } - /* - * The record should be written. If a locked ntfs - * inode was returned, add it to the array of locked - * ntfs inodes. - */ - if (tni) - locked_nis[nr_locked_nis++] = tni; - } - /* Apply the mst protection fixups. */ - err2 = pre_write_mst_fixup((NTFS_RECORD*)(kaddr + ofs), - rec_size); - if (unlikely(err2)) { - if (!err || err == -ENOMEM) - err = -EIO; - ntfs_error(vol->sb, "Failed to apply mst fixups " - "(inode 0x%lx, attribute type 0x%x, " - "page index 0x%lx, page offset 0x%x)!" - " Unmount and run chkdsk.", vi->i_ino, - ni->type, page->index, ofs); - /* - * Mark all the buffers in this record clean as we do - * not want to write corrupt data to disk. - */ - do { - clear_buffer_dirty(bhs[i]); - bhs[i] = NULL; - } while (++i % bhs_per_rec); - continue; - } - nr_recs++; - } - /* If no records are to be written out, we are done. */ - if (!nr_recs) - goto unm_done; - flush_dcache_page(page); - /* Lock buffers and start synchronous write i/o on them. */ - for (i = 0; i < nr_bhs; i++) { - tbh = bhs[i]; - if (!tbh) - continue; - if (!trylock_buffer(tbh)) - BUG(); - /* The buffer dirty state is now irrelevant, just clean it. */ - clear_buffer_dirty(tbh); - BUG_ON(!buffer_uptodate(tbh)); - BUG_ON(!buffer_mapped(tbh)); - get_bh(tbh); - tbh->b_end_io = end_buffer_write_sync; - submit_bh(REQ_OP_WRITE, tbh); - } - /* Synchronize the mft mirror now if not @sync. */ - if (is_mft && !sync) - goto do_mirror; -do_wait: - /* Wait on i/o completion of buffers. */ - for (i = 0; i < nr_bhs; i++) { - tbh = bhs[i]; - if (!tbh) - continue; - wait_on_buffer(tbh); - if (unlikely(!buffer_uptodate(tbh))) { - ntfs_error(vol->sb, "I/O error while writing ntfs " - "record buffer (inode 0x%lx, " - "attribute type 0x%x, page index " - "0x%lx, page offset 0x%lx)! Unmount " - "and run chkdsk.", vi->i_ino, ni->type, - page->index, bh_offset(tbh)); - if (!err || err == -ENOMEM) - err = -EIO; - /* - * Set the buffer uptodate so the page and buffer - * states do not become out of sync. - */ - set_buffer_uptodate(tbh); - } - } - /* If @sync, now synchronize the mft mirror. */ - if (is_mft && sync) { -do_mirror: - for (i = 0; i < nr_bhs; i++) { - unsigned long mft_no; - unsigned int ofs; - - /* - * Skip buffers which are not at the beginning of - * records. - */ - if (i % bhs_per_rec) - continue; - tbh = bhs[i]; - /* Skip removed buffers (and hence records). */ - if (!tbh) - continue; - ofs = bh_offset(tbh); - /* Get the mft record number. */ - mft_no = (((s64)page->index << PAGE_SHIFT) + ofs) - >> rec_size_bits; - if (mft_no < vol->mftmirr_size) - ntfs_sync_mft_mirror(vol, mft_no, - (MFT_RECORD*)(kaddr + ofs), - sync); - } - if (!sync) - goto do_wait; - } - /* Remove the mst protection fixups again. */ - for (i = 0; i < nr_bhs; i++) { - if (!(i % bhs_per_rec)) { - tbh = bhs[i]; - if (!tbh) - continue; - post_write_mst_fixup((NTFS_RECORD*)(kaddr + - bh_offset(tbh))); - } - } - flush_dcache_page(page); -unm_done: - /* Unlock any locked inodes. */ - while (nr_locked_nis-- > 0) { - ntfs_inode *tni, *base_tni; - - tni = locked_nis[nr_locked_nis]; - /* Get the base inode. */ - mutex_lock(&tni->extent_lock); - if (tni->nr_extents >= 0) - base_tni = tni; - else { - base_tni = tni->ext.base_ntfs_ino; - BUG_ON(!base_tni); - } - mutex_unlock(&tni->extent_lock); - ntfs_debug("Unlocking %s inode 0x%lx.", - tni == base_tni ? "base" : "extent", - tni->mft_no); - mutex_unlock(&tni->mrec_lock); - atomic_dec(&tni->count); - iput(VFS_I(base_tni)); - } - SetPageUptodate(page); - kunmap(page); -done: - if (unlikely(err && err != -ENOMEM)) { - /* - * Set page error if there is only one ntfs record in the page. - * Otherwise we would loose per-record granularity. - */ - if (ni->itype.index.block_size == PAGE_SIZE) - SetPageError(page); - NVolSetErrors(vol); - } - if (page_is_dirty) { - ntfs_debug("Page still contains one or more dirty ntfs " - "records. Redirtying the page starting at " - "record 0x%lx.", page->index << - (PAGE_SHIFT - rec_size_bits)); - redirty_page_for_writepage(wbc, page); - unlock_page(page); - } else { - /* - * Keep the VM happy. This must be done otherwise the - * radix-tree tag PAGECACHE_TAG_DIRTY remains set even though - * the page is clean. - */ - BUG_ON(PageWriteback(page)); - set_page_writeback(page); - unlock_page(page); - end_page_writeback(page); - } - if (likely(!err)) - ntfs_debug("Done."); - return err; -} - -/** - * ntfs_writepage - write a @page to the backing store - * @page: page cache page to write out - * @wbc: writeback control structure - * - * This is called from the VM when it wants to have a dirty ntfs page cache - * page cleaned. The VM has already locked the page and marked it clean. - * - * For non-resident attributes, ntfs_writepage() writes the @page by calling - * the ntfs version of the generic block_write_full_folio() function, - * ntfs_write_block(), which in turn if necessary creates and writes the - * buffers associated with the page asynchronously. - * - * For resident attributes, OTOH, ntfs_writepage() writes the @page by copying - * the data to the mft record (which at this stage is most likely in memory). - * The mft record is then marked dirty and written out asynchronously via the - * vfs inode dirty code path for the inode the mft record belongs to or via the - * vm page dirty code path for the page the mft record is in. - * - * Based on ntfs_read_folio() and fs/buffer.c::block_write_full_folio(). - * - * Return 0 on success and -errno on error. - */ -static int ntfs_writepage(struct page *page, struct writeback_control *wbc) -{ - struct folio *folio = page_folio(page); - loff_t i_size; - struct inode *vi = folio->mapping->host; - ntfs_inode *base_ni = NULL, *ni = NTFS_I(vi); - char *addr; - ntfs_attr_search_ctx *ctx = NULL; - MFT_RECORD *m = NULL; - u32 attr_len; - int err; - -retry_writepage: - BUG_ON(!folio_test_locked(folio)); - i_size = i_size_read(vi); - /* Is the folio fully outside i_size? (truncate in progress) */ - if (unlikely(folio->index >= (i_size + PAGE_SIZE - 1) >> - PAGE_SHIFT)) { - /* - * The folio may have dirty, unmapped buffers. Make them - * freeable here, so the page does not leak. - */ - block_invalidate_folio(folio, 0, folio_size(folio)); - folio_unlock(folio); - ntfs_debug("Write outside i_size - truncated?"); - return 0; - } - /* - * Only $DATA attributes can be encrypted and only unnamed $DATA - * attributes can be compressed. Index root can have the flags set but - * this means to create compressed/encrypted files, not that the - * attribute is compressed/encrypted. Note we need to check for - * AT_INDEX_ALLOCATION since this is the type of both directory and - * index inodes. - */ - if (ni->type != AT_INDEX_ALLOCATION) { - /* If file is encrypted, deny access, just like NT4. */ - if (NInoEncrypted(ni)) { - folio_unlock(folio); - BUG_ON(ni->type != AT_DATA); - ntfs_debug("Denying write access to encrypted file."); - return -EACCES; - } - /* Compressed data streams are handled in compress.c. */ - if (NInoNonResident(ni) && NInoCompressed(ni)) { - BUG_ON(ni->type != AT_DATA); - BUG_ON(ni->name_len); - // TODO: Implement and replace this with - // return ntfs_write_compressed_block(page); - folio_unlock(folio); - ntfs_error(vi->i_sb, "Writing to compressed files is " - "not supported yet. Sorry."); - return -EOPNOTSUPP; - } - // TODO: Implement and remove this check. - if (NInoNonResident(ni) && NInoSparse(ni)) { - folio_unlock(folio); - ntfs_error(vi->i_sb, "Writing to sparse files is not " - "supported yet. Sorry."); - return -EOPNOTSUPP; - } - } - /* NInoNonResident() == NInoIndexAllocPresent() */ - if (NInoNonResident(ni)) { - /* We have to zero every time due to mmap-at-end-of-file. */ - if (folio->index >= (i_size >> PAGE_SHIFT)) { - /* The folio straddles i_size. */ - unsigned int ofs = i_size & (folio_size(folio) - 1); - folio_zero_segment(folio, ofs, folio_size(folio)); - } - /* Handle mst protected attributes. */ - if (NInoMstProtected(ni)) - return ntfs_write_mst_block(page, wbc); - /* Normal, non-resident data stream. */ - return ntfs_write_block(folio, wbc); - } - /* - * Attribute is resident, implying it is not compressed, encrypted, or - * mst protected. This also means the attribute is smaller than an mft - * record and hence smaller than a folio, so can simply return error on - * any folios with index above 0. Note the attribute can actually be - * marked compressed but if it is resident the actual data is not - * compressed so we are ok to ignore the compressed flag here. - */ - BUG_ON(folio_buffers(folio)); - BUG_ON(!folio_test_uptodate(folio)); - if (unlikely(folio->index > 0)) { - ntfs_error(vi->i_sb, "BUG()! folio->index (0x%lx) > 0. " - "Aborting write.", folio->index); - BUG_ON(folio_test_writeback(folio)); - folio_start_writeback(folio); - folio_unlock(folio); - folio_end_writeback(folio); - return -EIO; - } - if (!NInoAttr(ni)) - base_ni = ni; - else - base_ni = ni->ext.base_ntfs_ino; - /* Map, pin, and lock the mft record. */ - m = map_mft_record(base_ni); - if (IS_ERR(m)) { - err = PTR_ERR(m); - m = NULL; - ctx = NULL; - goto err_out; - } - /* - * If a parallel write made the attribute non-resident, drop the mft - * record and retry the writepage. - */ - if (unlikely(NInoNonResident(ni))) { - unmap_mft_record(base_ni); - goto retry_writepage; - } - ctx = ntfs_attr_get_search_ctx(base_ni, m); - if (unlikely(!ctx)) { - err = -ENOMEM; - goto err_out; - } - err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len, - CASE_SENSITIVE, 0, NULL, 0, ctx); - if (unlikely(err)) - goto err_out; - /* - * Keep the VM happy. This must be done otherwise - * PAGECACHE_TAG_DIRTY remains set even though the folio is clean. - */ - BUG_ON(folio_test_writeback(folio)); - folio_start_writeback(folio); - folio_unlock(folio); - attr_len = le32_to_cpu(ctx->attr->data.resident.value_length); - i_size = i_size_read(vi); - if (unlikely(attr_len > i_size)) { - /* Race with shrinking truncate or a failed truncate. */ - attr_len = i_size; - /* - * If the truncate failed, fix it up now. If a concurrent - * truncate, we do its job, so it does not have to do anything. - */ - err = ntfs_resident_attr_value_resize(ctx->mrec, ctx->attr, - attr_len); - /* Shrinking cannot fail. */ - BUG_ON(err); - } - addr = kmap_local_folio(folio, 0); - /* Copy the data from the folio to the mft record. */ - memcpy((u8*)ctx->attr + - le16_to_cpu(ctx->attr->data.resident.value_offset), - addr, attr_len); - /* Zero out of bounds area in the page cache folio. */ - memset(addr + attr_len, 0, folio_size(folio) - attr_len); - kunmap_local(addr); - flush_dcache_folio(folio); - flush_dcache_mft_record_page(ctx->ntfs_ino); - /* We are done with the folio. */ - folio_end_writeback(folio); - /* Finally, mark the mft record dirty, so it gets written back. */ - mark_mft_record_dirty(ctx->ntfs_ino); - ntfs_attr_put_search_ctx(ctx); - unmap_mft_record(base_ni); - return 0; -err_out: - if (err == -ENOMEM) { - ntfs_warning(vi->i_sb, "Error allocating memory. Redirtying " - "page so we try again later."); - /* - * Put the folio back on mapping->dirty_pages, but leave its - * buffers' dirty state as-is. - */ - folio_redirty_for_writepage(wbc, folio); - err = 0; - } else { - ntfs_error(vi->i_sb, "Resident attribute write failed with " - "error %i.", err); - folio_set_error(folio); - NVolSetErrors(ni->vol); - } - folio_unlock(folio); - if (ctx) - ntfs_attr_put_search_ctx(ctx); - if (m) - unmap_mft_record(base_ni); - return err; -} - -#endif /* NTFS_RW */ - -/** - * ntfs_bmap - map logical file block to physical device block - * @mapping: address space mapping to which the block to be mapped belongs - * @block: logical block to map to its physical device block - * - * For regular, non-resident files (i.e. not compressed and not encrypted), map - * the logical @block belonging to the file described by the address space - * mapping @mapping to its physical device block. - * - * The size of the block is equal to the @s_blocksize field of the super block - * of the mounted file system which is guaranteed to be smaller than or equal - * to the cluster size thus the block is guaranteed to fit entirely inside the - * cluster which means we do not need to care how many contiguous bytes are - * available after the beginning of the block. - * - * Return the physical device block if the mapping succeeded or 0 if the block - * is sparse or there was an error. - * - * Note: This is a problem if someone tries to run bmap() on $Boot system file - * as that really is in block zero but there is nothing we can do. bmap() is - * just broken in that respect (just like it cannot distinguish sparse from - * not available or error). - */ -static sector_t ntfs_bmap(struct address_space *mapping, sector_t block) -{ - s64 ofs, size; - loff_t i_size; - LCN lcn; - unsigned long blocksize, flags; - ntfs_inode *ni = NTFS_I(mapping->host); - ntfs_volume *vol = ni->vol; - unsigned delta; - unsigned char blocksize_bits, cluster_size_shift; - - ntfs_debug("Entering for mft_no 0x%lx, logical block 0x%llx.", - ni->mft_no, (unsigned long long)block); - if (ni->type != AT_DATA || !NInoNonResident(ni) || NInoEncrypted(ni)) { - ntfs_error(vol->sb, "BMAP does not make sense for %s " - "attributes, returning 0.", - (ni->type != AT_DATA) ? "non-data" : - (!NInoNonResident(ni) ? "resident" : - "encrypted")); - return 0; - } - /* None of these can happen. */ - BUG_ON(NInoCompressed(ni)); - BUG_ON(NInoMstProtected(ni)); - blocksize = vol->sb->s_blocksize; - blocksize_bits = vol->sb->s_blocksize_bits; - ofs = (s64)block << blocksize_bits; - read_lock_irqsave(&ni->size_lock, flags); - size = ni->initialized_size; - i_size = i_size_read(VFS_I(ni)); - read_unlock_irqrestore(&ni->size_lock, flags); - /* - * If the offset is outside the initialized size or the block straddles - * the initialized size then pretend it is a hole unless the - * initialized size equals the file size. - */ - if (unlikely(ofs >= size || (ofs + blocksize > size && size < i_size))) - goto hole; - cluster_size_shift = vol->cluster_size_bits; - down_read(&ni->runlist.lock); - lcn = ntfs_attr_vcn_to_lcn_nolock(ni, ofs >> cluster_size_shift, false); - up_read(&ni->runlist.lock); - if (unlikely(lcn < LCN_HOLE)) { - /* - * Step down to an integer to avoid gcc doing a long long - * comparision in the switch when we know @lcn is between - * LCN_HOLE and LCN_EIO (i.e. -1 to -5). - * - * Otherwise older gcc (at least on some architectures) will - * try to use __cmpdi2() which is of course not available in - * the kernel. - */ - switch ((int)lcn) { - case LCN_ENOENT: - /* - * If the offset is out of bounds then pretend it is a - * hole. - */ - goto hole; - case LCN_ENOMEM: - ntfs_error(vol->sb, "Not enough memory to complete " - "mapping for inode 0x%lx. " - "Returning 0.", ni->mft_no); - break; - default: - ntfs_error(vol->sb, "Failed to complete mapping for " - "inode 0x%lx. Run chkdsk. " - "Returning 0.", ni->mft_no); - break; - } - return 0; - } - if (lcn < 0) { - /* It is a hole. */ -hole: - ntfs_debug("Done (returning hole)."); - return 0; - } - /* - * The block is really allocated and fullfils all our criteria. - * Convert the cluster to units of block size and return the result. - */ - delta = ofs & vol->cluster_size_mask; - if (unlikely(sizeof(block) < sizeof(lcn))) { - block = lcn = ((lcn << cluster_size_shift) + delta) >> - blocksize_bits; - /* If the block number was truncated return 0. */ - if (unlikely(block != lcn)) { - ntfs_error(vol->sb, "Physical block 0x%llx is too " - "large to be returned, returning 0.", - (long long)lcn); - return 0; - } - } else - block = ((lcn << cluster_size_shift) + delta) >> - blocksize_bits; - ntfs_debug("Done (returning block 0x%llx).", (unsigned long long)lcn); - return block; -} - -/* - * ntfs_normal_aops - address space operations for normal inodes and attributes - * - * Note these are not used for compressed or mst protected inodes and - * attributes. - */ -const struct address_space_operations ntfs_normal_aops = { - .read_folio = ntfs_read_folio, -#ifdef NTFS_RW - .writepage = ntfs_writepage, - .dirty_folio = block_dirty_folio, -#endif /* NTFS_RW */ - .bmap = ntfs_bmap, - .migrate_folio = buffer_migrate_folio, - .is_partially_uptodate = block_is_partially_uptodate, - .error_remove_folio = generic_error_remove_folio, -}; - -/* - * ntfs_compressed_aops - address space operations for compressed inodes - */ -const struct address_space_operations ntfs_compressed_aops = { - .read_folio = ntfs_read_folio, -#ifdef NTFS_RW - .writepage = ntfs_writepage, - .dirty_folio = block_dirty_folio, -#endif /* NTFS_RW */ - .migrate_folio = buffer_migrate_folio, - .is_partially_uptodate = block_is_partially_uptodate, - .error_remove_folio = generic_error_remove_folio, -}; - -/* - * ntfs_mst_aops - general address space operations for mst protecteed inodes - * and attributes - */ -const struct address_space_operations ntfs_mst_aops = { - .read_folio = ntfs_read_folio, /* Fill page with data. */ -#ifdef NTFS_RW - .writepage = ntfs_writepage, /* Write dirty page to disk. */ - .dirty_folio = filemap_dirty_folio, -#endif /* NTFS_RW */ - .migrate_folio = buffer_migrate_folio, - .is_partially_uptodate = block_is_partially_uptodate, - .error_remove_folio = generic_error_remove_folio, -}; - -#ifdef NTFS_RW - -/** - * mark_ntfs_record_dirty - mark an ntfs record dirty - * @page: page containing the ntfs record to mark dirty - * @ofs: byte offset within @page at which the ntfs record begins - * - * Set the buffers and the page in which the ntfs record is located dirty. - * - * The latter also marks the vfs inode the ntfs record belongs to dirty - * (I_DIRTY_PAGES only). - * - * If the page does not have buffers, we create them and set them uptodate. - * The page may not be locked which is why we need to handle the buffers under - * the mapping->i_private_lock. Once the buffers are marked dirty we no longer - * need the lock since try_to_free_buffers() does not free dirty buffers. - */ -void mark_ntfs_record_dirty(struct page *page, const unsigned int ofs) { - struct address_space *mapping = page->mapping; - ntfs_inode *ni = NTFS_I(mapping->host); - struct buffer_head *bh, *head, *buffers_to_free = NULL; - unsigned int end, bh_size, bh_ofs; - - BUG_ON(!PageUptodate(page)); - end = ofs + ni->itype.index.block_size; - bh_size = VFS_I(ni)->i_sb->s_blocksize; - spin_lock(&mapping->i_private_lock); - if (unlikely(!page_has_buffers(page))) { - spin_unlock(&mapping->i_private_lock); - bh = head = alloc_page_buffers(page, bh_size, true); - spin_lock(&mapping->i_private_lock); - if (likely(!page_has_buffers(page))) { - struct buffer_head *tail; - - do { - set_buffer_uptodate(bh); - tail = bh; - bh = bh->b_this_page; - } while (bh); - tail->b_this_page = head; - attach_page_private(page, head); - } else - buffers_to_free = bh; - } - bh = head = page_buffers(page); - BUG_ON(!bh); - do { - bh_ofs = bh_offset(bh); - if (bh_ofs + bh_size <= ofs) - continue; - if (unlikely(bh_ofs >= end)) - break; - set_buffer_dirty(bh); - } while ((bh = bh->b_this_page) != head); - spin_unlock(&mapping->i_private_lock); - filemap_dirty_folio(mapping, page_folio(page)); - if (unlikely(buffers_to_free)) { - do { - bh = buffers_to_free->b_this_page; - free_buffer_head(buffers_to_free); - buffers_to_free = bh; - } while (buffers_to_free); - } -} - -#endif /* NTFS_RW */ |