| /** |
| * dir.c - NTFS kernel directory operations. Part of the Linux-NTFS project. |
| * |
| * Copyright (c) 2001-2005 Anton Altaparmakov |
| * Copyright (c) 2002 Richard Russon |
| * |
| * This program/include file is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License as published |
| * by the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program/include file is distributed in the hope that it will be |
| * useful, but WITHOUT ANY WARRANTY; without even the implied warranty |
| * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program (in the main directory of the Linux-NTFS |
| * distribution in the file COPYING); if not, write to the Free Software |
| * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| |
| #include <linux/smp_lock.h> |
| #include <linux/buffer_head.h> |
| |
| #include "dir.h" |
| #include "aops.h" |
| #include "attrib.h" |
| #include "mft.h" |
| #include "debug.h" |
| #include "ntfs.h" |
| |
| /** |
| * The little endian Unicode string $I30 as a global constant. |
| */ |
| ntfschar I30[5] = { const_cpu_to_le16('$'), const_cpu_to_le16('I'), |
| const_cpu_to_le16('3'), const_cpu_to_le16('0'), 0 }; |
| |
| /** |
| * ntfs_lookup_inode_by_name - find an inode in a directory given its name |
| * @dir_ni: ntfs inode of the directory in which to search for the name |
| * @uname: Unicode name for which to search in the directory |
| * @uname_len: length of the name @uname in Unicode characters |
| * @res: return the found file name if necessary (see below) |
| * |
| * Look for an inode with name @uname in the directory with inode @dir_ni. |
| * ntfs_lookup_inode_by_name() walks the contents of the directory looking for |
| * the Unicode name. If the name is found in the directory, the corresponding |
| * inode number (>= 0) is returned as a mft reference in cpu format, i.e. it |
| * is a 64-bit number containing the sequence number. |
| * |
| * On error, a negative value is returned corresponding to the error code. In |
| * particular if the inode is not found -ENOENT is returned. Note that you |
| * can't just check the return value for being negative, you have to check the |
| * inode number for being negative which you can extract using MREC(return |
| * value). |
| * |
| * Note, @uname_len does not include the (optional) terminating NULL character. |
| * |
| * Note, we look for a case sensitive match first but we also look for a case |
| * insensitive match at the same time. If we find a case insensitive match, we |
| * save that for the case that we don't find an exact match, where we return |
| * the case insensitive match and setup @res (which we allocate!) with the mft |
| * reference, the file name type, length and with a copy of the little endian |
| * Unicode file name itself. If we match a file name which is in the DOS name |
| * space, we only return the mft reference and file name type in @res. |
| * ntfs_lookup() then uses this to find the long file name in the inode itself. |
| * This is to avoid polluting the dcache with short file names. We want them to |
| * work but we don't care for how quickly one can access them. This also fixes |
| * the dcache aliasing issues. |
| * |
| * Locking: - Caller must hold i_sem on the directory. |
| * - Each page cache page in the index allocation mapping must be |
| * locked whilst being accessed otherwise we may find a corrupt |
| * page due to it being under ->writepage at the moment which |
| * applies the mst protection fixups before writing out and then |
| * removes them again after the write is complete after which it |
| * unlocks the page. |
| */ |
| MFT_REF ntfs_lookup_inode_by_name(ntfs_inode *dir_ni, const ntfschar *uname, |
| const int uname_len, ntfs_name **res) |
| { |
| ntfs_volume *vol = dir_ni->vol; |
| struct super_block *sb = vol->sb; |
| MFT_RECORD *m; |
| INDEX_ROOT *ir; |
| INDEX_ENTRY *ie; |
| INDEX_ALLOCATION *ia; |
| u8 *index_end; |
| u64 mref; |
| ntfs_attr_search_ctx *ctx; |
| int err, rc; |
| VCN vcn, old_vcn; |
| struct address_space *ia_mapping; |
| struct page *page; |
| u8 *kaddr; |
| ntfs_name *name = NULL; |
| |
| BUG_ON(!S_ISDIR(VFS_I(dir_ni)->i_mode)); |
| BUG_ON(NInoAttr(dir_ni)); |
| /* Get hold of the mft record for the directory. */ |
| m = map_mft_record(dir_ni); |
| if (IS_ERR(m)) { |
| ntfs_error(sb, "map_mft_record() failed with error code %ld.", |
| -PTR_ERR(m)); |
| return ERR_MREF(PTR_ERR(m)); |
| } |
| ctx = ntfs_attr_get_search_ctx(dir_ni, m); |
| if (unlikely(!ctx)) { |
| err = -ENOMEM; |
| goto err_out; |
| } |
| /* Find the index root attribute in the mft record. */ |
| err = ntfs_attr_lookup(AT_INDEX_ROOT, I30, 4, CASE_SENSITIVE, 0, NULL, |
| 0, ctx); |
| if (unlikely(err)) { |
| if (err == -ENOENT) { |
| ntfs_error(sb, "Index root attribute missing in " |
| "directory inode 0x%lx.", |
| dir_ni->mft_no); |
| err = -EIO; |
| } |
| goto err_out; |
| } |
| /* Get to the index root value (it's been verified in read_inode). */ |
| ir = (INDEX_ROOT*)((u8*)ctx->attr + |
| le16_to_cpu(ctx->attr->data.resident.value_offset)); |
| index_end = (u8*)&ir->index + le32_to_cpu(ir->index.index_length); |
| /* The first index entry. */ |
| ie = (INDEX_ENTRY*)((u8*)&ir->index + |
| le32_to_cpu(ir->index.entries_offset)); |
| /* |
| * Loop until we exceed valid memory (corruption case) or until we |
| * reach the last entry. |
| */ |
| for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) { |
| /* Bounds checks. */ |
| if ((u8*)ie < (u8*)ctx->mrec || (u8*)ie + |
| sizeof(INDEX_ENTRY_HEADER) > index_end || |
| (u8*)ie + le16_to_cpu(ie->key_length) > |
| index_end) |
| goto dir_err_out; |
| /* |
| * The last entry cannot contain a name. It can however contain |
| * a pointer to a child node in the B+tree so we just break out. |
| */ |
| if (ie->flags & INDEX_ENTRY_END) |
| break; |
| /* |
| * We perform a case sensitive comparison and if that matches |
| * we are done and return the mft reference of the inode (i.e. |
| * the inode number together with the sequence number for |
| * consistency checking). We convert it to cpu format before |
| * returning. |
| */ |
| if (ntfs_are_names_equal(uname, uname_len, |
| (ntfschar*)&ie->key.file_name.file_name, |
| ie->key.file_name.file_name_length, |
| CASE_SENSITIVE, vol->upcase, vol->upcase_len)) { |
| found_it: |
| /* |
| * We have a perfect match, so we don't need to care |
| * about having matched imperfectly before, so we can |
| * free name and set *res to NULL. |
| * However, if the perfect match is a short file name, |
| * we need to signal this through *res, so that |
| * ntfs_lookup() can fix dcache aliasing issues. |
| * As an optimization we just reuse an existing |
| * allocation of *res. |
| */ |
| if (ie->key.file_name.file_name_type == FILE_NAME_DOS) { |
| if (!name) { |
| name = kmalloc(sizeof(ntfs_name), |
| GFP_NOFS); |
| if (!name) { |
| err = -ENOMEM; |
| goto err_out; |
| } |
| } |
| name->mref = le64_to_cpu( |
| ie->data.dir.indexed_file); |
| name->type = FILE_NAME_DOS; |
| name->len = 0; |
| *res = name; |
| } else { |
| kfree(name); |
| *res = NULL; |
| } |
| mref = le64_to_cpu(ie->data.dir.indexed_file); |
| ntfs_attr_put_search_ctx(ctx); |
| unmap_mft_record(dir_ni); |
| return mref; |
| } |
| /* |
| * For a case insensitive mount, we also perform a case |
| * insensitive comparison (provided the file name is not in the |
| * POSIX namespace). If the comparison matches, and the name is |
| * in the WIN32 namespace, we cache the filename in *res so |
| * that the caller, ntfs_lookup(), can work on it. If the |
| * comparison matches, and the name is in the DOS namespace, we |
| * only cache the mft reference and the file name type (we set |
| * the name length to zero for simplicity). |
| */ |
| if (!NVolCaseSensitive(vol) && |
| ie->key.file_name.file_name_type && |
| ntfs_are_names_equal(uname, uname_len, |
| (ntfschar*)&ie->key.file_name.file_name, |
| ie->key.file_name.file_name_length, |
| IGNORE_CASE, vol->upcase, vol->upcase_len)) { |
| int name_size = sizeof(ntfs_name); |
| u8 type = ie->key.file_name.file_name_type; |
| u8 len = ie->key.file_name.file_name_length; |
| |
| /* Only one case insensitive matching name allowed. */ |
| if (name) { |
| ntfs_error(sb, "Found already allocated name " |
| "in phase 1. Please run chkdsk " |
| "and if that doesn't find any " |
| "errors please report you saw " |
| "this message to " |
| "linux-ntfs-dev@lists." |
| "sourceforge.net."); |
| goto dir_err_out; |
| } |
| |
| if (type != FILE_NAME_DOS) |
| name_size += len * sizeof(ntfschar); |
| name = kmalloc(name_size, GFP_NOFS); |
| if (!name) { |
| err = -ENOMEM; |
| goto err_out; |
| } |
| name->mref = le64_to_cpu(ie->data.dir.indexed_file); |
| name->type = type; |
| if (type != FILE_NAME_DOS) { |
| name->len = len; |
| memcpy(name->name, ie->key.file_name.file_name, |
| len * sizeof(ntfschar)); |
| } else |
| name->len = 0; |
| *res = name; |
| } |
| /* |
| * Not a perfect match, need to do full blown collation so we |
| * know which way in the B+tree we have to go. |
| */ |
| rc = ntfs_collate_names(uname, uname_len, |
| (ntfschar*)&ie->key.file_name.file_name, |
| ie->key.file_name.file_name_length, 1, |
| IGNORE_CASE, vol->upcase, vol->upcase_len); |
| /* |
| * If uname collates before the name of the current entry, there |
| * is definitely no such name in this index but we might need to |
| * descend into the B+tree so we just break out of the loop. |
| */ |
| if (rc == -1) |
| break; |
| /* The names are not equal, continue the search. */ |
| if (rc) |
| continue; |
| /* |
| * Names match with case insensitive comparison, now try the |
| * case sensitive comparison, which is required for proper |
| * collation. |
| */ |
| rc = ntfs_collate_names(uname, uname_len, |
| (ntfschar*)&ie->key.file_name.file_name, |
| ie->key.file_name.file_name_length, 1, |
| CASE_SENSITIVE, vol->upcase, vol->upcase_len); |
| if (rc == -1) |
| break; |
| if (rc) |
| continue; |
| /* |
| * Perfect match, this will never happen as the |
| * ntfs_are_names_equal() call will have gotten a match but we |
| * still treat it correctly. |
| */ |
| goto found_it; |
| } |
| /* |
| * We have finished with this index without success. Check for the |
| * presence of a child node and if not present return -ENOENT, unless |
| * we have got a matching name cached in name in which case return the |
| * mft reference associated with it. |
| */ |
| if (!(ie->flags & INDEX_ENTRY_NODE)) { |
| if (name) { |
| ntfs_attr_put_search_ctx(ctx); |
| unmap_mft_record(dir_ni); |
| return name->mref; |
| } |
| ntfs_debug("Entry not found."); |
| err = -ENOENT; |
| goto err_out; |
| } /* Child node present, descend into it. */ |
| /* Consistency check: Verify that an index allocation exists. */ |
| if (!NInoIndexAllocPresent(dir_ni)) { |
| ntfs_error(sb, "No index allocation attribute but index entry " |
| "requires one. Directory inode 0x%lx is " |
| "corrupt or driver bug.", dir_ni->mft_no); |
| goto err_out; |
| } |
| /* Get the starting vcn of the index_block holding the child node. */ |
| vcn = sle64_to_cpup((sle64*)((u8*)ie + le16_to_cpu(ie->length) - 8)); |
| ia_mapping = VFS_I(dir_ni)->i_mapping; |
| /* |
| * We are done with the index root and the mft record. Release them, |
| * otherwise we deadlock with ntfs_map_page(). |
| */ |
| ntfs_attr_put_search_ctx(ctx); |
| unmap_mft_record(dir_ni); |
| m = NULL; |
| ctx = NULL; |
| descend_into_child_node: |
| /* |
| * Convert vcn to index into the index allocation attribute in units |
| * of PAGE_CACHE_SIZE and map the page cache page, reading it from |
| * disk if necessary. |
| */ |
| page = ntfs_map_page(ia_mapping, vcn << |
| dir_ni->itype.index.vcn_size_bits >> PAGE_CACHE_SHIFT); |
| if (IS_ERR(page)) { |
| ntfs_error(sb, "Failed to map directory index page, error %ld.", |
| -PTR_ERR(page)); |
| err = PTR_ERR(page); |
| goto err_out; |
| } |
| lock_page(page); |
| kaddr = (u8*)page_address(page); |
| fast_descend_into_child_node: |
| /* Get to the index allocation block. */ |
| ia = (INDEX_ALLOCATION*)(kaddr + ((vcn << |
| dir_ni->itype.index.vcn_size_bits) & ~PAGE_CACHE_MASK)); |
| /* Bounds checks. */ |
| if ((u8*)ia < kaddr || (u8*)ia > kaddr + PAGE_CACHE_SIZE) { |
| ntfs_error(sb, "Out of bounds check failed. Corrupt directory " |
| "inode 0x%lx or driver bug.", dir_ni->mft_no); |
| goto unm_err_out; |
| } |
| /* Catch multi sector transfer fixup errors. */ |
| if (unlikely(!ntfs_is_indx_record(ia->magic))) { |
| ntfs_error(sb, "Directory index record with vcn 0x%llx is " |
| "corrupt. Corrupt inode 0x%lx. Run chkdsk.", |
| (unsigned long long)vcn, dir_ni->mft_no); |
| goto unm_err_out; |
| } |
| if (sle64_to_cpu(ia->index_block_vcn) != vcn) { |
| ntfs_error(sb, "Actual VCN (0x%llx) of index buffer is " |
| "different from expected VCN (0x%llx). " |
| "Directory inode 0x%lx is corrupt or driver " |
| "bug.", (unsigned long long) |
| sle64_to_cpu(ia->index_block_vcn), |
| (unsigned long long)vcn, dir_ni->mft_no); |
| goto unm_err_out; |
| } |
| if (le32_to_cpu(ia->index.allocated_size) + 0x18 != |
| dir_ni->itype.index.block_size) { |
| ntfs_error(sb, "Index buffer (VCN 0x%llx) of directory inode " |
| "0x%lx has a size (%u) differing from the " |
| "directory specified size (%u). Directory " |
| "inode is corrupt or driver bug.", |
| (unsigned long long)vcn, dir_ni->mft_no, |
| le32_to_cpu(ia->index.allocated_size) + 0x18, |
| dir_ni->itype.index.block_size); |
| goto unm_err_out; |
| } |
| index_end = (u8*)ia + dir_ni->itype.index.block_size; |
| if (index_end > kaddr + PAGE_CACHE_SIZE) { |
| ntfs_error(sb, "Index buffer (VCN 0x%llx) of directory inode " |
| "0x%lx crosses page boundary. Impossible! " |
| "Cannot access! This is probably a bug in the " |
| "driver.", (unsigned long long)vcn, |
| dir_ni->mft_no); |
| goto unm_err_out; |
| } |
| index_end = (u8*)&ia->index + le32_to_cpu(ia->index.index_length); |
| if (index_end > (u8*)ia + dir_ni->itype.index.block_size) { |
| ntfs_error(sb, "Size of index buffer (VCN 0x%llx) of directory " |
| "inode 0x%lx exceeds maximum size.", |
| (unsigned long long)vcn, dir_ni->mft_no); |
| goto unm_err_out; |
| } |
| /* The first index entry. */ |
| ie = (INDEX_ENTRY*)((u8*)&ia->index + |
| le32_to_cpu(ia->index.entries_offset)); |
| /* |
| * Iterate similar to above big loop but applied to index buffer, thus |
| * loop until we exceed valid memory (corruption case) or until we |
| * reach the last entry. |
| */ |
| for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) { |
| /* Bounds check. */ |
| if ((u8*)ie < (u8*)ia || (u8*)ie + |
| sizeof(INDEX_ENTRY_HEADER) > index_end || |
| (u8*)ie + le16_to_cpu(ie->key_length) > |
| index_end) { |
| ntfs_error(sb, "Index entry out of bounds in " |
| "directory inode 0x%lx.", |
| dir_ni->mft_no); |
| goto unm_err_out; |
| } |
| /* |
| * The last entry cannot contain a name. It can however contain |
| * a pointer to a child node in the B+tree so we just break out. |
| */ |
| if (ie->flags & INDEX_ENTRY_END) |
| break; |
| /* |
| * We perform a case sensitive comparison and if that matches |
| * we are done and return the mft reference of the inode (i.e. |
| * the inode number together with the sequence number for |
| * consistency checking). We convert it to cpu format before |
| * returning. |
| */ |
| if (ntfs_are_names_equal(uname, uname_len, |
| (ntfschar*)&ie->key.file_name.file_name, |
| ie->key.file_name.file_name_length, |
| CASE_SENSITIVE, vol->upcase, vol->upcase_len)) { |
| found_it2: |
| /* |
| * We have a perfect match, so we don't need to care |
| * about having matched imperfectly before, so we can |
| * free name and set *res to NULL. |
| * However, if the perfect match is a short file name, |
| * we need to signal this through *res, so that |
| * ntfs_lookup() can fix dcache aliasing issues. |
| * As an optimization we just reuse an existing |
| * allocation of *res. |
| */ |
| if (ie->key.file_name.file_name_type == FILE_NAME_DOS) { |
| if (!name) { |
| name = kmalloc(sizeof(ntfs_name), |
| GFP_NOFS); |
| if (!name) { |
| err = -ENOMEM; |
| goto unm_err_out; |
| } |
| } |
| name->mref = le64_to_cpu( |
| ie->data.dir.indexed_file); |
| name->type = FILE_NAME_DOS; |
| name->len = 0; |
| *res = name; |
| } else { |
| kfree(name); |
| *res = NULL; |
| } |
| mref = le64_to_cpu(ie->data.dir.indexed_file); |
| unlock_page(page); |
| ntfs_unmap_page(page); |
| return mref; |
| } |
| /* |
| * For a case insensitive mount, we also perform a case |
| * insensitive comparison (provided the file name is not in the |
| * POSIX namespace). If the comparison matches, and the name is |
| * in the WIN32 namespace, we cache the filename in *res so |
| * that the caller, ntfs_lookup(), can work on it. If the |
| * comparison matches, and the name is in the DOS namespace, we |
| * only cache the mft reference and the file name type (we set |
| * the name length to zero for simplicity). |
| */ |
| if (!NVolCaseSensitive(vol) && |
| ie->key.file_name.file_name_type && |
| ntfs_are_names_equal(uname, uname_len, |
| (ntfschar*)&ie->key.file_name.file_name, |
| ie->key.file_name.file_name_length, |
| IGNORE_CASE, vol->upcase, vol->upcase_len)) { |
| int name_size = sizeof(ntfs_name); |
| u8 type = ie->key.file_name.file_name_type; |
| u8 len = ie->key.file_name.file_name_length; |
| |
| /* Only one case insensitive matching name allowed. */ |
| if (name) { |
| ntfs_error(sb, "Found already allocated name " |
| "in phase 2. Please run chkdsk " |
| "and if that doesn't find any " |
| "errors please report you saw " |
| "this message to " |
| "linux-ntfs-dev@lists." |
| "sourceforge.net."); |
| unlock_page(page); |
| ntfs_unmap_page(page); |
| goto dir_err_out; |
| } |
| |
| if (type != FILE_NAME_DOS) |
| name_size += len * sizeof(ntfschar); |
| name = kmalloc(name_size, GFP_NOFS); |
| if (!name) { |
| err = -ENOMEM; |
| goto unm_err_out; |
| } |
| name->mref = le64_to_cpu(ie->data.dir.indexed_file); |
| name->type = type; |
| if (type != FILE_NAME_DOS) { |
| name->len = len; |
| memcpy(name->name, ie->key.file_name.file_name, |
| len * sizeof(ntfschar)); |
| } else |
| name->len = 0; |
| *res = name; |
| } |
| /* |
| * Not a perfect match, need to do full blown collation so we |
| * know which way in the B+tree we have to go. |
| */ |
| rc = ntfs_collate_names(uname, uname_len, |
| (ntfschar*)&ie->key.file_name.file_name, |
| ie->key.file_name.file_name_length, 1, |
| IGNORE_CASE, vol->upcase, vol->upcase_len); |
| /* |
| * If uname collates before the name of the current entry, there |
| * is definitely no such name in this index but we might need to |
| * descend into the B+tree so we just break out of the loop. |
| */ |
| if (rc == -1) |
| break; |
| /* The names are not equal, continue the search. */ |
| if (rc) |
| continue; |
| /* |
| * Names match with case insensitive comparison, now try the |
| * case sensitive comparison, which is required for proper |
| * collation. |
| */ |
| rc = ntfs_collate_names(uname, uname_len, |
| (ntfschar*)&ie->key.file_name.file_name, |
| ie->key.file_name.file_name_length, 1, |
| CASE_SENSITIVE, vol->upcase, vol->upcase_len); |
| if (rc == -1) |
| break; |
| if (rc) |
| continue; |
| /* |
| * Perfect match, this will never happen as the |
| * ntfs_are_names_equal() call will have gotten a match but we |
| * still treat it correctly. |
| */ |
| goto found_it2; |
| } |
| /* |
| * We have finished with this index buffer without success. Check for |
| * the presence of a child node. |
| */ |
| if (ie->flags & INDEX_ENTRY_NODE) { |
| if ((ia->index.flags & NODE_MASK) == LEAF_NODE) { |
| ntfs_error(sb, "Index entry with child node found in " |
| "a leaf node in directory inode 0x%lx.", |
| dir_ni->mft_no); |
| goto unm_err_out; |
| } |
| /* Child node present, descend into it. */ |
| old_vcn = vcn; |
| vcn = sle64_to_cpup((sle64*)((u8*)ie + |
| le16_to_cpu(ie->length) - 8)); |
| if (vcn >= 0) { |
| /* If vcn is in the same page cache page as old_vcn we |
| * recycle the mapped page. */ |
| if (old_vcn << vol->cluster_size_bits >> |
| PAGE_CACHE_SHIFT == vcn << |
| vol->cluster_size_bits >> |
| PAGE_CACHE_SHIFT) |
| goto fast_descend_into_child_node; |
| unlock_page(page); |
| ntfs_unmap_page(page); |
| goto descend_into_child_node; |
| } |
| ntfs_error(sb, "Negative child node vcn in directory inode " |
| "0x%lx.", dir_ni->mft_no); |
| goto unm_err_out; |
| } |
| /* |
| * No child node present, return -ENOENT, unless we have got a matching |
| * name cached in name in which case return the mft reference |
| * associated with it. |
| */ |
| if (name) { |
| unlock_page(page); |
| ntfs_unmap_page(page); |
| return name->mref; |
| } |
| ntfs_debug("Entry not found."); |
| err = -ENOENT; |
| unm_err_out: |
| unlock_page(page); |
| ntfs_unmap_page(page); |
| err_out: |
| if (!err) |
| err = -EIO; |
| if (ctx) |
| ntfs_attr_put_search_ctx(ctx); |
| if (m) |
| unmap_mft_record(dir_ni); |
| if (name) { |
| kfree(name); |
| *res = NULL; |
| } |
| return ERR_MREF(err); |
| dir_err_out: |
| ntfs_error(sb, "Corrupt directory. Aborting lookup."); |
| goto err_out; |
| } |
| |
| #if 0 |
| |
| // TODO: (AIA) |
| // The algorithm embedded in this code will be required for the time when we |
| // want to support adding of entries to directories, where we require correct |
| // collation of file names in order not to cause corruption of the filesystem. |
| |
| /** |
| * ntfs_lookup_inode_by_name - find an inode in a directory given its name |
| * @dir_ni: ntfs inode of the directory in which to search for the name |
| * @uname: Unicode name for which to search in the directory |
| * @uname_len: length of the name @uname in Unicode characters |
| * |
| * Look for an inode with name @uname in the directory with inode @dir_ni. |
| * ntfs_lookup_inode_by_name() walks the contents of the directory looking for |
| * the Unicode name. If the name is found in the directory, the corresponding |
| * inode number (>= 0) is returned as a mft reference in cpu format, i.e. it |
| * is a 64-bit number containing the sequence number. |
| * |
| * On error, a negative value is returned corresponding to the error code. In |
| * particular if the inode is not found -ENOENT is returned. Note that you |
| * can't just check the return value for being negative, you have to check the |
| * inode number for being negative which you can extract using MREC(return |
| * value). |
| * |
| * Note, @uname_len does not include the (optional) terminating NULL character. |
| */ |
| u64 ntfs_lookup_inode_by_name(ntfs_inode *dir_ni, const ntfschar *uname, |
| const int uname_len) |
| { |
| ntfs_volume *vol = dir_ni->vol; |
| struct super_block *sb = vol->sb; |
| MFT_RECORD *m; |
| INDEX_ROOT *ir; |
| INDEX_ENTRY *ie; |
| INDEX_ALLOCATION *ia; |
| u8 *index_end; |
| u64 mref; |
| ntfs_attr_search_ctx *ctx; |
| int err, rc; |
| IGNORE_CASE_BOOL ic; |
| VCN vcn, old_vcn; |
| struct address_space *ia_mapping; |
| struct page *page; |
| u8 *kaddr; |
| |
| /* Get hold of the mft record for the directory. */ |
| m = map_mft_record(dir_ni); |
| if (IS_ERR(m)) { |
| ntfs_error(sb, "map_mft_record() failed with error code %ld.", |
| -PTR_ERR(m)); |
| return ERR_MREF(PTR_ERR(m)); |
| } |
| ctx = ntfs_attr_get_search_ctx(dir_ni, m); |
| if (!ctx) { |
| err = -ENOMEM; |
| goto err_out; |
| } |
| /* Find the index root attribute in the mft record. */ |
| err = ntfs_attr_lookup(AT_INDEX_ROOT, I30, 4, CASE_SENSITIVE, 0, NULL, |
| 0, ctx); |
| if (unlikely(err)) { |
| if (err == -ENOENT) { |
| ntfs_error(sb, "Index root attribute missing in " |
| "directory inode 0x%lx.", |
| dir_ni->mft_no); |
| err = -EIO; |
| } |
| goto err_out; |
| } |
| /* Get to the index root value (it's been verified in read_inode). */ |
| ir = (INDEX_ROOT*)((u8*)ctx->attr + |
| le16_to_cpu(ctx->attr->data.resident.value_offset)); |
| index_end = (u8*)&ir->index + le32_to_cpu(ir->index.index_length); |
| /* The first index entry. */ |
| ie = (INDEX_ENTRY*)((u8*)&ir->index + |
| le32_to_cpu(ir->index.entries_offset)); |
| /* |
| * Loop until we exceed valid memory (corruption case) or until we |
| * reach the last entry. |
| */ |
| for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) { |
| /* Bounds checks. */ |
| if ((u8*)ie < (u8*)ctx->mrec || (u8*)ie + |
| sizeof(INDEX_ENTRY_HEADER) > index_end || |
| (u8*)ie + le16_to_cpu(ie->key_length) > |
| index_end) |
| goto dir_err_out; |
| /* |
| * The last entry cannot contain a name. It can however contain |
| * a pointer to a child node in the B+tree so we just break out. |
| */ |
| if (ie->flags & INDEX_ENTRY_END) |
| break; |
| /* |
| * If the current entry has a name type of POSIX, the name is |
| * case sensitive and not otherwise. This has the effect of us |
| * not being able to access any POSIX file names which collate |
| * after the non-POSIX one when they only differ in case, but |
| * anyone doing screwy stuff like that deserves to burn in |
| * hell... Doing that kind of stuff on NT4 actually causes |
| * corruption on the partition even when using SP6a and Linux |
| * is not involved at all. |
| */ |
| ic = ie->key.file_name.file_name_type ? IGNORE_CASE : |
| CASE_SENSITIVE; |
| /* |
| * If the names match perfectly, we are done and return the |
| * mft reference of the inode (i.e. the inode number together |
| * with the sequence number for consistency checking. We |
| * convert it to cpu format before returning. |
| */ |
| if (ntfs_are_names_equal(uname, uname_len, |
| (ntfschar*)&ie->key.file_name.file_name, |
| ie->key.file_name.file_name_length, ic, |
| vol->upcase, vol->upcase_len)) { |
| found_it: |
| mref = le64_to_cpu(ie->data.dir.indexed_file); |
| ntfs_attr_put_search_ctx(ctx); |
| unmap_mft_record(dir_ni); |
| return mref; |
| } |
| /* |
| * Not a perfect match, need to do full blown collation so we |
| * know which way in the B+tree we have to go. |
| */ |
| rc = ntfs_collate_names(uname, uname_len, |
| (ntfschar*)&ie->key.file_name.file_name, |
| ie->key.file_name.file_name_length, 1, |
| IGNORE_CASE, vol->upcase, vol->upcase_len); |
| /* |
| * If uname collates before the name of the current entry, there |
| * is definitely no such name in this index but we might need to |
| * descend into the B+tree so we just break out of the loop. |
| */ |
| if (rc == -1) |
| break; |
| /* The names are not equal, continue the search. */ |
| if (rc) |
| continue; |
| /* |
| * Names match with case insensitive comparison, now try the |
| * case sensitive comparison, which is required for proper |
| * collation. |
| */ |
| rc = ntfs_collate_names(uname, uname_len, |
| (ntfschar*)&ie->key.file_name.file_name, |
| ie->key.file_name.file_name_length, 1, |
| CASE_SENSITIVE, vol->upcase, vol->upcase_len); |
| if (rc == -1) |
| break; |
| if (rc) |
| continue; |
| /* |
| * Perfect match, this will never happen as the |
| * ntfs_are_names_equal() call will have gotten a match but we |
| * still treat it correctly. |
| */ |
| goto found_it; |
| } |
| /* |
| * We have finished with this index without success. Check for the |
| * presence of a child node. |
| */ |
| if (!(ie->flags & INDEX_ENTRY_NODE)) { |
| /* No child node, return -ENOENT. */ |
| err = -ENOENT; |
| goto err_out; |
| } /* Child node present, descend into it. */ |
| /* Consistency check: Verify that an index allocation exists. */ |
| if (!NInoIndexAllocPresent(dir_ni)) { |
| ntfs_error(sb, "No index allocation attribute but index entry " |
| "requires one. Directory inode 0x%lx is " |
| "corrupt or driver bug.", dir_ni->mft_no); |
| goto err_out; |
| } |
| /* Get the starting vcn of the index_block holding the child node. */ |
| vcn = sle64_to_cpup((u8*)ie + le16_to_cpu(ie->length) - 8); |
| ia_mapping = VFS_I(dir_ni)->i_mapping; |
| /* |
| * We are done with the index root and the mft record. Release them, |
| * otherwise we deadlock with ntfs_map_page(). |
| */ |
| ntfs_attr_put_search_ctx(ctx); |
| unmap_mft_record(dir_ni); |
| m = NULL; |
| ctx = NULL; |
| descend_into_child_node: |
| /* |
| * Convert vcn to index into the index allocation attribute in units |
| * of PAGE_CACHE_SIZE and map the page cache page, reading it from |
| * disk if necessary. |
| */ |
| page = ntfs_map_page(ia_mapping, vcn << |
| dir_ni->itype.index.vcn_size_bits >> PAGE_CACHE_SHIFT); |
| if (IS_ERR(page)) { |
| ntfs_error(sb, "Failed to map directory index page, error %ld.", |
| -PTR_ERR(page)); |
| err = PTR_ERR(page); |
| goto err_out; |
| } |
| lock_page(page); |
| kaddr = (u8*)page_address(page); |
| fast_descend_into_child_node: |
| /* Get to the index allocation block. */ |
| ia = (INDEX_ALLOCATION*)(kaddr + ((vcn << |
| dir_ni->itype.index.vcn_size_bits) & ~PAGE_CACHE_MASK)); |
| /* Bounds checks. */ |
| if ((u8*)ia < kaddr || (u8*)ia > kaddr + PAGE_CACHE_SIZE) { |
| ntfs_error(sb, "Out of bounds check failed. Corrupt directory " |
| "inode 0x%lx or driver bug.", dir_ni->mft_no); |
| goto unm_err_out; |
| } |
| /* Catch multi sector transfer fixup errors. */ |
| if (unlikely(!ntfs_is_indx_record(ia->magic))) { |
| ntfs_error(sb, "Directory index record with vcn 0x%llx is " |
| "corrupt. Corrupt inode 0x%lx. Run chkdsk.", |
| (unsigned long long)vcn, dir_ni->mft_no); |
| goto unm_err_out; |
| } |
| if (sle64_to_cpu(ia->index_block_vcn) != vcn) { |
| ntfs_error(sb, "Actual VCN (0x%llx) of index buffer is " |
| "different from expected VCN (0x%llx). " |
| "Directory inode 0x%lx is corrupt or driver " |
| "bug.", (unsigned long long) |
| sle64_to_cpu(ia->index_block_vcn), |
| (unsigned long long)vcn, dir_ni->mft_no); |
| goto unm_err_out; |
| } |
| if (le32_to_cpu(ia->index.allocated_size) + 0x18 != |
| dir_ni->itype.index.block_size) { |
| ntfs_error(sb, "Index buffer (VCN 0x%llx) of directory inode " |
| "0x%lx has a size (%u) differing from the " |
| "directory specified size (%u). Directory " |
| "inode is corrupt or driver bug.", |
| (unsigned long long)vcn, dir_ni->mft_no, |
| le32_to_cpu(ia->index.allocated_size) + 0x18, |
| dir_ni->itype.index.block_size); |
| goto unm_err_out; |
| } |
| index_end = (u8*)ia + dir_ni->itype.index.block_size; |
| if (index_end > kaddr + PAGE_CACHE_SIZE) { |
| ntfs_error(sb, "Index buffer (VCN 0x%llx) of directory inode " |
| "0x%lx crosses page boundary. Impossible! " |
| "Cannot access! This is probably a bug in the " |
| "driver.", (unsigned long long)vcn, |
| dir_ni->mft_no); |
| goto unm_err_out; |
| } |
| index_end = (u8*)&ia->index + le32_to_cpu(ia->index.index_length); |
| if (index_end > (u8*)ia + dir_ni->itype.index.block_size) { |
| ntfs_error(sb, "Size of index buffer (VCN 0x%llx) of directory " |
| "inode 0x%lx exceeds maximum size.", |
| (unsigned long long)vcn, dir_ni->mft_no); |
| goto unm_err_out; |
| } |
| /* The first index entry. */ |
| ie = (INDEX_ENTRY*)((u8*)&ia->index + |
| le32_to_cpu(ia->index.entries_offset)); |
| /* |
| * Iterate similar to above big loop but applied to index buffer, thus |
| * loop until we exceed valid memory (corruption case) or until we |
| * reach the last entry. |
| */ |
| for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) { |
| /* Bounds check. */ |
| if ((u8*)ie < (u8*)ia || (u8*)ie + |
| sizeof(INDEX_ENTRY_HEADER) > index_end || |
| (u8*)ie + le16_to_cpu(ie->key_length) > |
| index_end) { |
| ntfs_error(sb, "Index entry out of bounds in " |
| "directory inode 0x%lx.", |
| dir_ni->mft_no); |
| goto unm_err_out; |
| } |
| /* |
| * The last entry cannot contain a name. It can however contain |
| * a pointer to a child node in the B+tree so we just break out. |
| */ |
| if (ie->flags & INDEX_ENTRY_END) |
| break; |
| /* |
| * If the current entry has a name type of POSIX, the name is |
| * case sensitive and not otherwise. This has the effect of us |
| * not being able to access any POSIX file names which collate |
| * after the non-POSIX one when they only differ in case, but |
| * anyone doing screwy stuff like that deserves to burn in |
| * hell... Doing that kind of stuff on NT4 actually causes |
| * corruption on the partition even when using SP6a and Linux |
| * is not involved at all. |
| */ |
| ic = ie->key.file_name.file_name_type ? IGNORE_CASE : |
| CASE_SENSITIVE; |
| /* |
| * If the names match perfectly, we are done and return the |
| * mft reference of the inode (i.e. the inode number together |
| * with the sequence number for consistency checking. We |
| * convert it to cpu format before returning. |
| */ |
| if (ntfs_are_names_equal(uname, uname_len, |
| (ntfschar*)&ie->key.file_name.file_name, |
| ie->key.file_name.file_name_length, ic, |
| vol->upcase, vol->upcase_len)) { |
| found_it2: |
| mref = le64_to_cpu(ie->data.dir.indexed_file); |
| unlock_page(page); |
| ntfs_unmap_page(page); |
| return mref; |
| } |
| /* |
| * Not a perfect match, need to do full blown collation so we |
| * know which way in the B+tree we have to go. |
| */ |
| rc = ntfs_collate_names(uname, uname_len, |
| (ntfschar*)&ie->key.file_name.file_name, |
| ie->key.file_name.file_name_length, 1, |
| IGNORE_CASE, vol->upcase, vol->upcase_len); |
| /* |
| * If uname collates before the name of the current entry, there |
| * is definitely no such name in this index but we might need to |
| * descend into the B+tree so we just break out of the loop. |
| */ |
| if (rc == -1) |
| break; |
| /* The names are not equal, continue the search. */ |
| if (rc) |
| continue; |
| /* |
| * Names match with case insensitive comparison, now try the |
| * case sensitive comparison, which is required for proper |
| * collation. |
| */ |
| rc = ntfs_collate_names(uname, uname_len, |
| (ntfschar*)&ie->key.file_name.file_name, |
| ie->key.file_name.file_name_length, 1, |
| CASE_SENSITIVE, vol->upcase, vol->upcase_len); |
| if (rc == -1) |
| break; |
| if (rc) |
| continue; |
| /* |
| * Perfect match, this will never happen as the |
| * ntfs_are_names_equal() call will have gotten a match but we |
| * still treat it correctly. |
| */ |
| goto found_it2; |
| } |
| /* |
| * We have finished with this index buffer without success. Check for |
| * the presence of a child node. |
| */ |
| if (ie->flags & INDEX_ENTRY_NODE) { |
| if ((ia->index.flags & NODE_MASK) == LEAF_NODE) { |
| ntfs_error(sb, "Index entry with child node found in " |
| "a leaf node in directory inode 0x%lx.", |
| dir_ni->mft_no); |
| goto unm_err_out; |
| } |
| /* Child node present, descend into it. */ |
| old_vcn = vcn; |
| vcn = sle64_to_cpup((u8*)ie + le16_to_cpu(ie->length) - 8); |
| if (vcn >= 0) { |
| /* If vcn is in the same page cache page as old_vcn we |
| * recycle the mapped page. */ |
| if (old_vcn << vol->cluster_size_bits >> |
| PAGE_CACHE_SHIFT == vcn << |
| vol->cluster_size_bits >> |
| PAGE_CACHE_SHIFT) |
| goto fast_descend_into_child_node; |
| unlock_page(page); |
| ntfs_unmap_page(page); |
| goto descend_into_child_node; |
| } |
| ntfs_error(sb, "Negative child node vcn in directory inode " |
| "0x%lx.", dir_ni->mft_no); |
| goto unm_err_out; |
| } |
| /* No child node, return -ENOENT. */ |
| ntfs_debug("Entry not found."); |
| err = -ENOENT; |
| unm_err_out: |
| unlock_page(page); |
| ntfs_unmap_page(page); |
| err_out: |
| if (!err) |
| err = -EIO; |
| if (ctx) |
| ntfs_attr_put_search_ctx(ctx); |
| if (m) |
| unmap_mft_record(dir_ni); |
| return ERR_MREF(err); |
| dir_err_out: |
| ntfs_error(sb, "Corrupt directory. Aborting lookup."); |
| goto err_out; |
| } |
| |
| #endif |
| |
| /** |
| * ntfs_filldir - ntfs specific filldir method |
| * @vol: current ntfs volume |
| * @fpos: position in the directory |
| * @ndir: ntfs inode of current directory |
| * @ia_page: page in which the index allocation buffer @ie is in resides |
| * @ie: current index entry |
| * @name: buffer to use for the converted name |
| * @dirent: vfs filldir callback context |
| * @filldir: vfs filldir callback |
| * |
| * Convert the Unicode @name to the loaded NLS and pass it to the @filldir |
| * callback. |
| * |
| * If @ia_page is not NULL it is the locked page containing the index |
| * allocation block containing the index entry @ie. |
| * |
| * Note, we drop (and then reacquire) the page lock on @ia_page across the |
| * @filldir() call otherwise we would deadlock with NFSd when it calls ->lookup |
| * since ntfs_lookup() will lock the same page. As an optimization, we do not |
| * retake the lock if we are returning a non-zero value as ntfs_readdir() |
| * would need to drop the lock immediately anyway. |
| */ |
| static inline int ntfs_filldir(ntfs_volume *vol, loff_t fpos, |
| ntfs_inode *ndir, struct page *ia_page, INDEX_ENTRY *ie, |
| u8 *name, void *dirent, filldir_t filldir) |
| { |
| unsigned long mref; |
| int name_len, rc; |
| unsigned dt_type; |
| FILE_NAME_TYPE_FLAGS name_type; |
| |
| name_type = ie->key.file_name.file_name_type; |
| if (name_type == FILE_NAME_DOS) { |
| ntfs_debug("Skipping DOS name space entry."); |
| return 0; |
| } |
| if (MREF_LE(ie->data.dir.indexed_file) == FILE_root) { |
| ntfs_debug("Skipping root directory self reference entry."); |
| return 0; |
| } |
| if (MREF_LE(ie->data.dir.indexed_file) < FILE_first_user && |
| !NVolShowSystemFiles(vol)) { |
| ntfs_debug("Skipping system file."); |
| return 0; |
| } |
| name_len = ntfs_ucstonls(vol, (ntfschar*)&ie->key.file_name.file_name, |
| ie->key.file_name.file_name_length, &name, |
| NTFS_MAX_NAME_LEN * NLS_MAX_CHARSET_SIZE + 1); |
| if (name_len <= 0) { |
| ntfs_debug("Skipping unrepresentable file."); |
| return 0; |
| } |
| if (ie->key.file_name.file_attributes & |
| FILE_ATTR_DUP_FILE_NAME_INDEX_PRESENT) |
| dt_type = DT_DIR; |
| else |
| dt_type = DT_REG; |
| mref = MREF_LE(ie->data.dir.indexed_file); |
| /* |
| * Drop the page lock otherwise we deadlock with NFS when it calls |
| * ->lookup since ntfs_lookup() will lock the same page. |
| */ |
| if (ia_page) |
| unlock_page(ia_page); |
| ntfs_debug("Calling filldir for %s with len %i, fpos 0x%llx, inode " |
| "0x%lx, DT_%s.", name, name_len, fpos, mref, |
| dt_type == DT_DIR ? "DIR" : "REG"); |
| rc = filldir(dirent, name, name_len, fpos, mref, dt_type); |
| /* Relock the page but not if we are aborting ->readdir. */ |
| if (!rc && ia_page) |
| lock_page(ia_page); |
| return rc; |
| } |
| |
| /* |
| * We use the same basic approach as the old NTFS driver, i.e. we parse the |
| * index root entries and then the index allocation entries that are marked |
| * as in use in the index bitmap. |
| * |
| * While this will return the names in random order this doesn't matter for |
| * ->readdir but OTOH results in a faster ->readdir. |
| * |
| * VFS calls ->readdir without BKL but with i_sem held. This protects the VFS |
| * parts (e.g. ->f_pos and ->i_size, and it also protects against directory |
| * modifications). |
| * |
| * Locking: - Caller must hold i_sem on the directory. |
| * - Each page cache page in the index allocation mapping must be |
| * locked whilst being accessed otherwise we may find a corrupt |
| * page due to it being under ->writepage at the moment which |
| * applies the mst protection fixups before writing out and then |
| * removes them again after the write is complete after which it |
| * unlocks the page. |
| */ |
| static int ntfs_readdir(struct file *filp, void *dirent, filldir_t filldir) |
| { |
| s64 ia_pos, ia_start, prev_ia_pos, bmp_pos; |
| loff_t fpos, i_size; |
| struct inode *bmp_vi, *vdir = filp->f_dentry->d_inode; |
| struct super_block *sb = vdir->i_sb; |
| ntfs_inode *ndir = NTFS_I(vdir); |
| ntfs_volume *vol = NTFS_SB(sb); |
| MFT_RECORD *m; |
| INDEX_ROOT *ir = NULL; |
| INDEX_ENTRY *ie; |
| INDEX_ALLOCATION *ia; |
| u8 *name = NULL; |
| int rc, err, ir_pos, cur_bmp_pos; |
| struct address_space *ia_mapping, *bmp_mapping; |
| struct page *bmp_page = NULL, *ia_page = NULL; |
| u8 *kaddr, *bmp, *index_end; |
| ntfs_attr_search_ctx *ctx; |
| |
| fpos = filp->f_pos; |
| ntfs_debug("Entering for inode 0x%lx, fpos 0x%llx.", |
| vdir->i_ino, fpos); |
| rc = err = 0; |
| /* Are we at end of dir yet? */ |
| i_size = i_size_read(vdir); |
| if (fpos >= i_size + vol->mft_record_size) |
| goto done; |
| /* Emulate . and .. for all directories. */ |
| if (!fpos) { |
| ntfs_debug("Calling filldir for . with len 1, fpos 0x0, " |
| "inode 0x%lx, DT_DIR.", vdir->i_ino); |
| rc = filldir(dirent, ".", 1, fpos, vdir->i_ino, DT_DIR); |
| if (rc) |
| goto done; |
| fpos++; |
| } |
| if (fpos == 1) { |
| ntfs_debug("Calling filldir for .. with len 2, fpos 0x1, " |
| "inode 0x%lx, DT_DIR.", |
| parent_ino(filp->f_dentry)); |
| rc = filldir(dirent, "..", 2, fpos, |
| parent_ino(filp->f_dentry), DT_DIR); |
| if (rc) |
| goto done; |
| fpos++; |
| } |
| m = NULL; |
| ctx = NULL; |
| /* |
| * Allocate a buffer to store the current name being processed |
| * converted to format determined by current NLS. |
| */ |
| name = (u8*)kmalloc(NTFS_MAX_NAME_LEN * NLS_MAX_CHARSET_SIZE + 1, |
| GFP_NOFS); |
| if (unlikely(!name)) { |
| err = -ENOMEM; |
| goto err_out; |
| } |
| /* Are we jumping straight into the index allocation attribute? */ |
| if (fpos >= vol->mft_record_size) |
| goto skip_index_root; |
| /* Get hold of the mft record for the directory. */ |
| m = map_mft_record(ndir); |
| if (IS_ERR(m)) { |
| err = PTR_ERR(m); |
| m = NULL; |
| goto err_out; |
| } |
| ctx = ntfs_attr_get_search_ctx(ndir, m); |
| if (unlikely(!ctx)) { |
| err = -ENOMEM; |
| goto err_out; |
| } |
| /* Get the offset into the index root attribute. */ |
| ir_pos = (s64)fpos; |
| /* Find the index root attribute in the mft record. */ |
| err = ntfs_attr_lookup(AT_INDEX_ROOT, I30, 4, CASE_SENSITIVE, 0, NULL, |
| 0, ctx); |
| if (unlikely(err)) { |
| ntfs_error(sb, "Index root attribute missing in directory " |
| "inode 0x%lx.", vdir->i_ino); |
| goto err_out; |
| } |
| /* |
| * Copy the index root attribute value to a buffer so that we can put |
| * the search context and unmap the mft record before calling the |
| * filldir() callback. We need to do this because of NFSd which calls |
| * ->lookup() from its filldir callback() and this causes NTFS to |
| * deadlock as ntfs_lookup() maps the mft record of the directory and |
| * we have got it mapped here already. The only solution is for us to |
| * unmap the mft record here so that a call to ntfs_lookup() is able to |
| * map the mft record without deadlocking. |
| */ |
| rc = le32_to_cpu(ctx->attr->data.resident.value_length); |
| ir = (INDEX_ROOT*)kmalloc(rc, GFP_NOFS); |
| if (unlikely(!ir)) { |
| err = -ENOMEM; |
| goto err_out; |
| } |
| /* Copy the index root value (it has been verified in read_inode). */ |
| memcpy(ir, (u8*)ctx->attr + |
| le16_to_cpu(ctx->attr->data.resident.value_offset), rc); |
| ntfs_attr_put_search_ctx(ctx); |
| unmap_mft_record(ndir); |
| ctx = NULL; |
| m = NULL; |
| index_end = (u8*)&ir->index + le32_to_cpu(ir->index.index_length); |
| /* The first index entry. */ |
| ie = (INDEX_ENTRY*)((u8*)&ir->index + |
| le32_to_cpu(ir->index.entries_offset)); |
| /* |
| * Loop until we exceed valid memory (corruption case) or until we |
| * reach the last entry or until filldir tells us it has had enough |
| * or signals an error (both covered by the rc test). |
| */ |
| for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) { |
| ntfs_debug("In index root, offset 0x%zx.", (u8*)ie - (u8*)ir); |
| /* Bounds checks. */ |
| if (unlikely((u8*)ie < (u8*)ir || (u8*)ie + |
| sizeof(INDEX_ENTRY_HEADER) > index_end || |
| (u8*)ie + le16_to_cpu(ie->key_length) > |
| index_end)) |
| goto err_out; |
| /* The last entry cannot contain a name. */ |
| if (ie->flags & INDEX_ENTRY_END) |
| break; |
| /* Skip index root entry if continuing previous readdir. */ |
| if (ir_pos > (u8*)ie - (u8*)ir) |
| continue; |
| /* Advance the position even if going to skip the entry. */ |
| fpos = (u8*)ie - (u8*)ir; |
| /* Submit the name to the filldir callback. */ |
| rc = ntfs_filldir(vol, fpos, ndir, NULL, ie, name, dirent, |
| filldir); |
| if (rc) { |
| kfree(ir); |
| goto abort; |
| } |
| } |
| /* We are done with the index root and can free the buffer. */ |
| kfree(ir); |
| ir = NULL; |
| /* If there is no index allocation attribute we are finished. */ |
| if (!NInoIndexAllocPresent(ndir)) |
| goto EOD; |
| /* Advance fpos to the beginning of the index allocation. */ |
| fpos = vol->mft_record_size; |
| skip_index_root: |
| kaddr = NULL; |
| prev_ia_pos = -1LL; |
| /* Get the offset into the index allocation attribute. */ |
| ia_pos = (s64)fpos - vol->mft_record_size; |
| ia_mapping = vdir->i_mapping; |
| bmp_vi = ndir->itype.index.bmp_ino; |
| if (unlikely(!bmp_vi)) { |
| ntfs_debug("Inode 0x%lx, regetting index bitmap.", vdir->i_ino); |
| bmp_vi = ntfs_attr_iget(vdir, AT_BITMAP, I30, 4); |
| if (IS_ERR(bmp_vi)) { |
| ntfs_error(sb, "Failed to get bitmap attribute."); |
| err = PTR_ERR(bmp_vi); |
| goto err_out; |
| } |
| ndir->itype.index.bmp_ino = bmp_vi; |
| } |
| bmp_mapping = bmp_vi->i_mapping; |
| /* Get the starting bitmap bit position and sanity check it. */ |
| bmp_pos = ia_pos >> ndir->itype.index.block_size_bits; |
| if (unlikely(bmp_pos >> 3 >= i_size_read(bmp_vi))) { |
| ntfs_error(sb, "Current index allocation position exceeds " |
| "index bitmap size."); |
| goto err_out; |
| } |
| /* Get the starting bit position in the current bitmap page. */ |
| cur_bmp_pos = bmp_pos & ((PAGE_CACHE_SIZE * 8) - 1); |
| bmp_pos &= ~(u64)((PAGE_CACHE_SIZE * 8) - 1); |
| get_next_bmp_page: |
| ntfs_debug("Reading bitmap with page index 0x%llx, bit ofs 0x%llx", |
| (unsigned long long)bmp_pos >> (3 + PAGE_CACHE_SHIFT), |
| (unsigned long long)bmp_pos & |
| (unsigned long long)((PAGE_CACHE_SIZE * 8) - 1)); |
| bmp_page = ntfs_map_page(bmp_mapping, |
| bmp_pos >> (3 + PAGE_CACHE_SHIFT)); |
| if (IS_ERR(bmp_page)) { |
| ntfs_error(sb, "Reading index bitmap failed."); |
| err = PTR_ERR(bmp_page); |
| bmp_page = NULL; |
| goto err_out; |
| } |
| bmp = (u8*)page_address(bmp_page); |
| /* Find next index block in use. */ |
| while (!(bmp[cur_bmp_pos >> 3] & (1 << (cur_bmp_pos & 7)))) { |
| find_next_index_buffer: |
| cur_bmp_pos++; |
| /* |
| * If we have reached the end of the bitmap page, get the next |
| * page, and put away the old one. |
| */ |
| if (unlikely((cur_bmp_pos >> 3) >= PAGE_CACHE_SIZE)) { |
| ntfs_unmap_page(bmp_page); |
| bmp_pos += PAGE_CACHE_SIZE * 8; |
| cur_bmp_pos = 0; |
| goto get_next_bmp_page; |
| } |
| /* If we have reached the end of the bitmap, we are done. */ |
| if (unlikely(((bmp_pos + cur_bmp_pos) >> 3) >= i_size)) |
| goto unm_EOD; |
| ia_pos = (bmp_pos + cur_bmp_pos) << |
| ndir->itype.index.block_size_bits; |
| } |
| ntfs_debug("Handling index buffer 0x%llx.", |
| (unsigned long long)bmp_pos + cur_bmp_pos); |
| /* If the current index buffer is in the same page we reuse the page. */ |
| if ((prev_ia_pos & (s64)PAGE_CACHE_MASK) != |
| (ia_pos & (s64)PAGE_CACHE_MASK)) { |
| prev_ia_pos = ia_pos; |
| if (likely(ia_page != NULL)) { |
| unlock_page(ia_page); |
| ntfs_unmap_page(ia_page); |
| } |
| /* |
| * Map the page cache page containing the current ia_pos, |
| * reading it from disk if necessary. |
| */ |
| ia_page = ntfs_map_page(ia_mapping, ia_pos >> PAGE_CACHE_SHIFT); |
| if (IS_ERR(ia_page)) { |
| ntfs_error(sb, "Reading index allocation data failed."); |
| err = PTR_ERR(ia_page); |
| ia_page = NULL; |
| goto err_out; |
| } |
| lock_page(ia_page); |
| kaddr = (u8*)page_address(ia_page); |
| } |
| /* Get the current index buffer. */ |
| ia = (INDEX_ALLOCATION*)(kaddr + (ia_pos & ~PAGE_CACHE_MASK & |
| ~(s64)(ndir->itype.index.block_size - 1))); |
| /* Bounds checks. */ |
| if (unlikely((u8*)ia < kaddr || (u8*)ia > kaddr + PAGE_CACHE_SIZE)) { |
| ntfs_error(sb, "Out of bounds check failed. Corrupt directory " |
| "inode 0x%lx or driver bug.", vdir->i_ino); |
| goto err_out; |
| } |
| /* Catch multi sector transfer fixup errors. */ |
| if (unlikely(!ntfs_is_indx_record(ia->magic))) { |
| ntfs_error(sb, "Directory index record with vcn 0x%llx is " |
| "corrupt. Corrupt inode 0x%lx. Run chkdsk.", |
| (unsigned long long)ia_pos >> |
| ndir->itype.index.vcn_size_bits, vdir->i_ino); |
| goto err_out; |
| } |
| if (unlikely(sle64_to_cpu(ia->index_block_vcn) != (ia_pos & |
| ~(s64)(ndir->itype.index.block_size - 1)) >> |
| ndir->itype.index.vcn_size_bits)) { |
| ntfs_error(sb, "Actual VCN (0x%llx) of index buffer is " |
| "different from expected VCN (0x%llx). " |
| "Directory inode 0x%lx is corrupt or driver " |
| "bug. ", (unsigned long long) |
| sle64_to_cpu(ia->index_block_vcn), |
| (unsigned long long)ia_pos >> |
| ndir->itype.index.vcn_size_bits, vdir->i_ino); |
| goto err_out; |
| } |
| if (unlikely(le32_to_cpu(ia->index.allocated_size) + 0x18 != |
| ndir->itype.index.block_size)) { |
| ntfs_error(sb, "Index buffer (VCN 0x%llx) of directory inode " |
| "0x%lx has a size (%u) differing from the " |
| "directory specified size (%u). Directory " |
| "inode is corrupt or driver bug.", |
| (unsigned long long)ia_pos >> |
| ndir->itype.index.vcn_size_bits, vdir->i_ino, |
| le32_to_cpu(ia->index.allocated_size) + 0x18, |
| ndir->itype.index.block_size); |
| goto err_out; |
| } |
| index_end = (u8*)ia + ndir->itype.index.block_size; |
| if (unlikely(index_end > kaddr + PAGE_CACHE_SIZE)) { |
| ntfs_error(sb, "Index buffer (VCN 0x%llx) of directory inode " |
| "0x%lx crosses page boundary. Impossible! " |
| "Cannot access! This is probably a bug in the " |
| "driver.", (unsigned long long)ia_pos >> |
| ndir->itype.index.vcn_size_bits, vdir->i_ino); |
| goto err_out; |
| } |
| ia_start = ia_pos & ~(s64)(ndir->itype.index.block_size - 1); |
| index_end = (u8*)&ia->index + le32_to_cpu(ia->index.index_length); |
| if (unlikely(index_end > (u8*)ia + ndir->itype.index.block_size)) { |
| ntfs_error(sb, "Size of index buffer (VCN 0x%llx) of directory " |
| "inode 0x%lx exceeds maximum size.", |
| (unsigned long long)ia_pos >> |
| ndir->itype.index.vcn_size_bits, vdir->i_ino); |
| goto err_out; |
| } |
| /* The first index entry in this index buffer. */ |
| ie = (INDEX_ENTRY*)((u8*)&ia->index + |
| le32_to_cpu(ia->index.entries_offset)); |
| /* |
| * Loop until we exceed valid memory (corruption case) or until we |
| * reach the last entry or until filldir tells us it has had enough |
| * or signals an error (both covered by the rc test). |
| */ |
| for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) { |
| ntfs_debug("In index allocation, offset 0x%llx.", |
| (unsigned long long)ia_start + |
| (unsigned long long)((u8*)ie - (u8*)ia)); |
| /* Bounds checks. */ |
| if (unlikely((u8*)ie < (u8*)ia || (u8*)ie + |
| sizeof(INDEX_ENTRY_HEADER) > index_end || |
| (u8*)ie + le16_to_cpu(ie->key_length) > |
| index_end)) |
| goto err_out; |
| /* The last entry cannot contain a name. */ |
| if (ie->flags & INDEX_ENTRY_END) |
| break; |
| /* Skip index block entry if continuing previous readdir. */ |
| if (ia_pos - ia_start > (u8*)ie - (u8*)ia) |
| continue; |
| /* Advance the position even if going to skip the entry. */ |
| fpos = (u8*)ie - (u8*)ia + |
| (sle64_to_cpu(ia->index_block_vcn) << |
| ndir->itype.index.vcn_size_bits) + |
| vol->mft_record_size; |
| /* |
| * Submit the name to the @filldir callback. Note, |
| * ntfs_filldir() drops the lock on @ia_page but it retakes it |
| * before returning, unless a non-zero value is returned in |
| * which case the page is left unlocked. |
| */ |
| rc = ntfs_filldir(vol, fpos, ndir, ia_page, ie, name, dirent, |
| filldir); |
| if (rc) { |
| /* @ia_page is already unlocked in this case. */ |
| ntfs_unmap_page(ia_page); |
| ntfs_unmap_page(bmp_page); |
| goto abort; |
| } |
| } |
| goto find_next_index_buffer; |
| unm_EOD: |
| if (ia_page) { |
| unlock_page(ia_page); |
| ntfs_unmap_page(ia_page); |
| } |
| ntfs_unmap_page(bmp_page); |
| EOD: |
| /* We are finished, set fpos to EOD. */ |
| fpos = i_size + vol->mft_record_size; |
| abort: |
| kfree(name); |
| done: |
| #ifdef DEBUG |
| if (!rc) |
| ntfs_debug("EOD, fpos 0x%llx, returning 0.", fpos); |
| else |
| ntfs_debug("filldir returned %i, fpos 0x%llx, returning 0.", |
| rc, fpos); |
| #endif |
| filp->f_pos = fpos; |
| return 0; |
| err_out: |
| if (bmp_page) |
| ntfs_unmap_page(bmp_page); |
| if (ia_page) { |
| unlock_page(ia_page); |
| ntfs_unmap_page(ia_page); |
| } |
| kfree(ir); |
| kfree(name); |
| if (ctx) |
| ntfs_attr_put_search_ctx(ctx); |
| if (m) |
| unmap_mft_record(ndir); |
| if (!err) |
| err = -EIO; |
| ntfs_debug("Failed. Returning error code %i.", -err); |
| filp->f_pos = fpos; |
| return err; |
| } |
| |
| /** |
| * ntfs_dir_open - called when an inode is about to be opened |
| * @vi: inode to be opened |
| * @filp: file structure describing the inode |
| * |
| * Limit directory size to the page cache limit on architectures where unsigned |
| * long is 32-bits. This is the most we can do for now without overflowing the |
| * page cache page index. Doing it this way means we don't run into problems |
| * because of existing too large directories. It would be better to allow the |
| * user to read the accessible part of the directory but I doubt very much |
| * anyone is going to hit this check on a 32-bit architecture, so there is no |
| * point in adding the extra complexity required to support this. |
| * |
| * On 64-bit architectures, the check is hopefully optimized away by the |
| * compiler. |
| */ |
| static int ntfs_dir_open(struct inode *vi, struct file *filp) |
| { |
| if (sizeof(unsigned long) < 8) { |
| if (i_size_read(vi) > MAX_LFS_FILESIZE) |
| return -EFBIG; |
| } |
| return 0; |
| } |
| |
| #ifdef NTFS_RW |
| |
| /** |
| * ntfs_dir_fsync - sync a directory to disk |
| * @filp: directory to be synced |
| * @dentry: dentry describing the directory to sync |
| * @datasync: if non-zero only flush user data and not metadata |
| * |
| * Data integrity sync of a directory to disk. Used for fsync, fdatasync, and |
| * msync system calls. This function is based on file.c::ntfs_file_fsync(). |
| * |
| * Write the mft record and all associated extent mft records as well as the |
| * $INDEX_ALLOCATION and $BITMAP attributes and then sync the block device. |
| * |
| * If @datasync is true, we do not wait on the inode(s) to be written out |
| * but we always wait on the page cache pages to be written out. |
| * |
| * Note: In the past @filp could be NULL so we ignore it as we don't need it |
| * anyway. |
| * |
| * Locking: Caller must hold i_sem on the inode. |
| * |
| * TODO: We should probably also write all attribute/index inodes associated |
| * with this inode but since we have no simple way of getting to them we ignore |
| * this problem for now. We do write the $BITMAP attribute if it is present |
| * which is the important one for a directory so things are not too bad. |
| */ |
| static int ntfs_dir_fsync(struct file *filp, struct dentry *dentry, |
| int datasync) |
| { |
| struct inode *vi = dentry->d_inode; |
| ntfs_inode *ni = NTFS_I(vi); |
| int err, ret; |
| |
| ntfs_debug("Entering for inode 0x%lx.", vi->i_ino); |
| BUG_ON(!S_ISDIR(vi->i_mode)); |
| if (NInoIndexAllocPresent(ni) && ni->itype.index.bmp_ino) |
| write_inode_now(ni->itype.index.bmp_ino, !datasync); |
| ret = ntfs_write_inode(vi, 1); |
| write_inode_now(vi, !datasync); |
| err = sync_blockdev(vi->i_sb->s_bdev); |
| if (unlikely(err && !ret)) |
| ret = err; |
| if (likely(!ret)) |
| ntfs_debug("Done."); |
| else |
| ntfs_warning(vi->i_sb, "Failed to f%ssync inode 0x%lx. Error " |
| "%u.", datasync ? "data" : "", vi->i_ino, -ret); |
| return ret; |
| } |
| |
| #endif /* NTFS_RW */ |
| |
| struct file_operations ntfs_dir_ops = { |
| .llseek = generic_file_llseek, /* Seek inside directory. */ |
| .read = generic_read_dir, /* Return -EISDIR. */ |
| .readdir = ntfs_readdir, /* Read directory contents. */ |
| #ifdef NTFS_RW |
| .fsync = ntfs_dir_fsync, /* Sync a directory to disk. */ |
| /*.aio_fsync = ,*/ /* Sync all outstanding async |
| i/o operations on a kiocb. */ |
| #endif /* NTFS_RW */ |
| /*.ioctl = ,*/ /* Perform function on the |
| mounted filesystem. */ |
| .open = ntfs_dir_open, /* Open directory. */ |
| }; |