cregit-Linux how code gets into the kernel

Release 4.11 fs/ntfs/dir.c

Directory: fs/ntfs
/**
 * dir.c - NTFS kernel directory operations. Part of the Linux-NTFS project.
 *
 * Copyright (c) 2001-2007 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/buffer_head.h>
#include <linux/slab.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] = { cpu_to_le16('$'), cpu_to_le16('I'),
		cpu_to_le16('3'),	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_mutex 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_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_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_MASK)); /* Bounds checks. */ if ((u8*)ia < kaddr || (u8*)ia > kaddr + PAGE_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_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_SHIFT == vcn << vol->cluster_size_bits >> PAGE_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; }

Contributors

PersonTokensPropCommitsCommitProp
Anton Altaparmakov231199.70%1588.24%
Kirill A. Shutemov70.30%211.76%
Total2318100.00%17100.00%

#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_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_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_MASK)); /* Bounds checks. */ if ((u8*)ia < kaddr || (u8*)ia > kaddr + PAGE_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_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_SHIFT == vcn << vol->cluster_size_bits >> PAGE_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 * @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 * @actor: what to feed the entries to * * 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, ntfs_inode *ndir, struct page *ia_page, INDEX_ENTRY *ie, u8 *name, struct dir_context *actor) { unsigned long mref; int name_len; 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_warning(vol->sb, "Skipping unrepresentable inode 0x%llx.", (long long)MREF_LE(ie->data.dir.indexed_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, actor->pos, mref, dt_type == DT_DIR ? "DIR" : "REG"); if (!dir_emit(actor, name, name_len, mref, dt_type)) return 1; /* Relock the page but not if we are aborting ->readdir. */ if (ia_page) lock_page(ia_page); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Anton Altaparmakov28494.67%1090.91%
Al Viro165.33%19.09%
Total300100.00%11100.00%

/* * 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_mutex 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_mutex 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 *file, struct dir_context *actor) { s64 ia_pos, ia_start, prev_ia_pos, bmp_pos; loff_t i_size; struct inode *bmp_vi, *vdir = file_inode(file); 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; ntfs_debug("Entering for inode 0x%lx, fpos 0x%llx.", vdir->i_ino, actor->pos); rc = err = 0; /* Are we at end of dir yet? */ i_size = i_size_read(vdir); if (actor->pos >= i_size + vol->mft_record_size) return 0; /* Emulate . and .. for all directories. */ if (!dir_emit_dots(file, actor)) return 0; m = NULL; ctx = NULL; /* * Allocate a buffer to store the current name being processed * converted to format determined by current NLS. */ name = 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 (actor->pos >= 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)actor->pos; /* 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 = 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. */ actor->pos = (u8*)ie - (u8*)ir; /* Submit the name to the filldir callback. */ rc = ntfs_filldir(vol, ndir, NULL, ie, name, actor); 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. */ actor->pos = vol->mft_record_size; skip_index_root: kaddr = NULL; prev_ia_pos = -1LL; /* Get the offset into the index allocation attribute. */ ia_pos = (s64)actor->pos - vol->mft_record_size; ia_mapping = vdir->i_mapping; ntfs_debug("Inode 0x%lx, getting 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; } 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 iput_err_out; } /* Get the starting bit position in the current bitmap page. */ cur_bmp_pos = bmp_pos & ((PAGE_SIZE * 8) - 1); bmp_pos &= ~(u64)((PAGE_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_SHIFT), (unsigned long long)bmp_pos & (unsigned long long)((PAGE_SIZE * 8) - 1)); bmp_page = ntfs_map_page(bmp_mapping, bmp_pos >> (3 + PAGE_SHIFT)); if (IS_ERR(bmp_page)) { ntfs_error(sb, "Reading index bitmap failed."); err = PTR_ERR(bmp_page); bmp_page = NULL; goto iput_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_SIZE)) { ntfs_unmap_page(bmp_page); bmp_pos += PAGE_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_MASK) != (ia_pos & (s64)PAGE_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_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_MASK & ~(s64)(ndir->itype.index.block_size - 1))); /* Bounds checks. */ if (unlikely((u8*)ia < kaddr || (u8*)ia > kaddr + PAGE_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_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. */ actor->pos = (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, ndir, ia_page, ie, name, actor); if (rc) { /* @ia_page is already unlocked in this case. */ ntfs_unmap_page(ia_page); ntfs_unmap_page(bmp_page); iput(bmp_vi); 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); iput(bmp_vi); EOD: /* We are finished, set fpos to EOD. */ actor->pos = i_size + vol->mft_record_size; abort: kfree(name); return 0; err_out: if (bmp_page) { ntfs_unmap_page(bmp_page); iput_err_out: iput(bmp_vi); } 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); return err; }

Contributors

PersonTokensPropCommitsCommitProp
Anton Altaparmakov193696.99%2083.33%
Al Viro472.35%312.50%
Kirill A. Shutemov130.65%14.17%
Total1996100.00%24100.00%

/** * 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; }

Contributors

PersonTokensPropCommitsCommitProp
Anton Altaparmakov44100.00%2100.00%
Total44100.00%2100.00%

#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_mutex 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, loff_t start, loff_t end, int datasync) { struct inode *bmp_vi, *vi = filp->f_mapping->host; int err, ret; ntfs_attr na; ntfs_debug("Entering for inode 0x%lx.", vi->i_ino); err = filemap_write_and_wait_range(vi->i_mapping, start, end); if (err) return err; inode_lock(vi); BUG_ON(!S_ISDIR(vi->i_mode)); /* If the bitmap attribute inode is in memory sync it, too. */ na.mft_no = vi->i_ino; na.type = AT_BITMAP; na.name = I30; na.name_len = 4; bmp_vi = ilookup5(vi->i_sb, vi->i_ino, (test_t)ntfs_test_inode, &na); if (bmp_vi) { write_inode_now(bmp_vi, !datasync); iput(bmp_vi); } 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); inode_unlock(vi); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Anton Altaparmakov20082.99%233.33%
Josef Bacik3414.11%116.67%
Christoph Hellwig52.07%233.33%
Al Viro20.83%116.67%
Total241100.00%6100.00%

#endif /* NTFS_RW */ const struct file_operations ntfs_dir_ops = { .llseek = generic_file_llseek, /* Seek inside directory. */ .read = generic_read_dir, /* Return -EISDIR. */ .iterate = ntfs_readdir, /* Read directory contents. */ #ifdef NTFS_RW .fsync = ntfs_dir_fsync, /* Sync a directory to disk. */ #endif /* NTFS_RW */ /*.ioctl = ,*/ /* Perform function on the mounted filesystem. */ .open = ntfs_dir_open, /* Open directory. */ };

Overall Contributors

PersonTokensPropCommitsCommitProp
Anton Altaparmakov495797.20%3170.45%
Al Viro671.31%49.09%
Josef Bacik340.67%12.27%
Kirill A. Shutemov260.51%24.55%
Christoph Hellwig50.10%24.55%
Harvey Harrison40.08%12.27%
Jes Sorensen30.06%12.27%
Tejun Heo30.06%12.27%
Arjan van de Ven10.02%12.27%
Total5100100.00%44100.00%
Directory: fs/ntfs
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