diff --git a/libntfs/logfile.c b/libntfs/logfile.c new file mode 100644 index 00000000..125f49df --- /dev/null +++ b/libntfs/logfile.c @@ -0,0 +1,716 @@ +/* + * logfile.c - NTFS journal handling. Part of the Linux-NTFS project. + * + * Copyright (c) 2002-2004 Anton Altaparmakov + * Copyright (c) 2005 Yura Pakhuchiy + * + * 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 + +#include "attrib.h" +#include "debug.h" +#include "logfile.h" +#include "volume.h" +#include "mst.h" + +/** + * ntfs_check_restart_page_header - check the page header for consistency + * @rp: restart page header to check + * @pos: position in logfile at which the restart page header resides + * + * Check the restart page header @rp for consistency and return TRUE if it is + * consistent and FALSE otherwise. + * + * This function only needs NTFS_BLOCK_SIZE bytes in @rp, i.e. it does not + * require the full restart page. + */ +static BOOL ntfs_check_restart_page_header(RESTART_PAGE_HEADER *rp, s64 pos) +{ + u32 logfile_system_page_size, logfile_log_page_size; + u16 usa_count, usa_ofs, usa_end, ra_ofs; + + ntfs_debug("Entering."); + /* + * If the system or log page sizes are smaller than the ntfs block size + * or either is not a power of 2 we cannot handle this log file. + */ + logfile_system_page_size = le32_to_cpu(rp->system_page_size); + logfile_log_page_size = le32_to_cpu(rp->log_page_size); + if (logfile_system_page_size < NTFS_BLOCK_SIZE || + logfile_log_page_size < NTFS_BLOCK_SIZE || + logfile_system_page_size & + (logfile_system_page_size - 1) || + logfile_log_page_size & (logfile_log_page_size - 1)) { + ntfs_error(vi->i_sb, "$LogFile uses unsupported page size."); + return FALSE; + } + /* + * We must be either at !pos (1st restart page) or at pos = system page + * size (2nd restart page). + */ + if (pos && pos != logfile_system_page_size) { + ntfs_error(vi->i_sb, "Found restart area in incorrect " + "position in $LogFile."); + return FALSE; + } + /* We only know how to handle version 1.1. */ + if (sle16_to_cpu(rp->major_ver) != 1 || + sle16_to_cpu(rp->minor_ver) != 1) { + ntfs_error(vi->i_sb, "$LogFile version %i.%i is not " + "supported. (This driver supports version " + "1.1 only.)", (int)sle16_to_cpu(rp->major_ver), + (int)sle16_to_cpu(rp->minor_ver)); + return FALSE; + } + /* Verify the size of the update sequence array. */ + usa_count = 1 + (logfile_system_page_size >> NTFS_BLOCK_SIZE_BITS); + if (usa_count != le16_to_cpu(rp->usa_count)) { + ntfs_error(vi->i_sb, "$LogFile restart page specifies " + "inconsistent update sequence array count."); + return FALSE; + } + /* Verify the position of the update sequence array. */ + usa_ofs = le16_to_cpu(rp->usa_ofs); + usa_end = usa_ofs + usa_count * sizeof(u16); + if (usa_ofs < sizeof(RESTART_PAGE_HEADER) || + usa_end > NTFS_BLOCK_SIZE - sizeof(u16)) { + ntfs_error(vi->i_sb, "$LogFile restart page specifies " + "inconsistent update sequence array offset."); + return FALSE; + } + /* + * Verify the position of the restart area. It must be: + * - aligned to 8-byte boundary, + * - after the update sequence array, and + * - within the system page size. + */ + ra_ofs = le16_to_cpu(rp->restart_area_offset); + if (ra_ofs & 7 || ra_ofs < usa_end || + ra_ofs > logfile_system_page_size) { + ntfs_error(vi->i_sb, "$LogFile restart page specifies " + "inconsistent restart area offset."); + return FALSE; + } + /* + * Only restart pages modified by chkdsk are allowed to have chkdsk_lsn + * set. + */ + if (!ntfs_is_chkd_record(rp->magic) && sle64_to_cpu(rp->chkdsk_lsn)) { + ntfs_error(vi->i_sb, "$LogFile restart page is not modified " + "chkdsk but a chkdsk LSN is specified."); + return FALSE; + } + ntfs_debug("Done."); + return TRUE; +} + +/** + * ntfs_check_restart_area - check the restart area for consistency + * @rp: restart page whose restart area to check + * + * Check the restart area of the restart page @rp for consistency and return + * TRUE if it is consistent and FALSE otherwise. + * + * This function assumes that the restart page header has already been + * consistency checked. + * + * This function only needs NTFS_BLOCK_SIZE bytes in @rp, i.e. it does not + * require the full restart page. + */ +static BOOL ntfs_check_restart_area(RESTART_PAGE_HEADER *rp) +{ + u64 file_size; + RESTART_AREA *ra; + u16 ra_ofs, ra_len, ca_ofs; + u8 fs_bits; + + ntfs_debug("Entering."); + ra_ofs = le16_to_cpu(rp->restart_area_offset); + ra = (RESTART_AREA*)((u8*)rp + ra_ofs); + /* + * Everything before ra->file_size must be before the first word + * protected by an update sequence number. This ensures that it is + * safe to access ra->client_array_offset. + */ + if (ra_ofs + offsetof(RESTART_AREA, file_size) > + NTFS_BLOCK_SIZE - sizeof(u16)) { + ntfs_error(vi->i_sb, "$LogFile restart area specifies " + "inconsistent file offset."); + return FALSE; + } + /* + * Now that we can access ra->client_array_offset, make sure everything + * up to the log client array is before the first word protected by an + * update sequence number. This ensures we can access all of the + * restart area elements safely. Also, the client array offset must be + * aligned to an 8-byte boundary. + */ + ca_ofs = le16_to_cpu(ra->client_array_offset); + if (((ca_ofs + 7) & ~7) != ca_ofs || + ra_ofs + ca_ofs > NTFS_BLOCK_SIZE - sizeof(u16)) { + ntfs_error(vi->i_sb, "$LogFile restart area specifies " + "inconsistent client array offset."); + return FALSE; + } + /* + * The restart area must end within the system page size both when + * calculated manually and as specified by ra->restart_area_length. + * Also, the calculated length must not exceed the specified length. + */ + ra_len = ca_ofs + le16_to_cpu(ra->log_clients) * + sizeof(LOG_CLIENT_RECORD); + if (ra_ofs + ra_len > le32_to_cpu(rp->system_page_size) || + ra_ofs + le16_to_cpu(ra->restart_area_length) > + le32_to_cpu(rp->system_page_size) || + ra_len > le16_to_cpu(ra->restart_area_length)) { + ntfs_error(vi->i_sb, "$LogFile restart area is out of bounds " + "of the system page size specified by the " + "restart page header and/or the specified " + "restart area length is inconsistent."); + return FALSE; + } + /* + * The ra->client_free_list and ra->client_in_use_list must be either + * LOGFILE_NO_CLIENT or less than ra->log_clients or they are + * overflowing the client array. + */ + if ((ra->client_free_list != LOGFILE_NO_CLIENT && + le16_to_cpu(ra->client_free_list) >= + le16_to_cpu(ra->log_clients)) || + (ra->client_in_use_list != LOGFILE_NO_CLIENT && + le16_to_cpu(ra->client_in_use_list) >= + le16_to_cpu(ra->log_clients))) { + ntfs_error(vi->i_sb, "$LogFile restart area specifies " + "overflowing client free and/or in use lists."); + return FALSE; + } + /* + * Check ra->seq_number_bits against ra->file_size for consistency. + * We cannot just use ffs() because the file size is not a power of 2. + */ + file_size = (u64)sle64_to_cpu(ra->file_size); + fs_bits = 0; + while (file_size) { + file_size >>= 1; + fs_bits++; + } + if (le32_to_cpu(ra->seq_number_bits) != (u32)(67 - fs_bits)) { + ntfs_error(vi->i_sb, "$LogFile restart area specifies " + "inconsistent sequence number bits."); + return FALSE; + } + /* The log record header length must be a multiple of 8. */ + if (((le16_to_cpu(ra->log_record_header_length) + 7) & ~7) != + le16_to_cpu(ra->log_record_header_length)) { + ntfs_error(vi->i_sb, "$LogFile restart area specifies " + "inconsistent log record header length."); + return FALSE; + } + /* Dito for the log page data offset. */ + if (((le16_to_cpu(ra->log_page_data_offset) + 7) & ~7) != + le16_to_cpu(ra->log_page_data_offset)) { + ntfs_error(vi->i_sb, "$LogFile restart area specifies " + "inconsistent log page data offset."); + return FALSE; + } + ntfs_debug("Done."); + return TRUE; +} + +/** + * ntfs_check_log_client_array - check the log client array for consistency + * @rp: restart page whose log client array to check + * + * Check the log client array of the restart page @rp for consistency and + * return TRUE if it is consistent and FALSE otherwise. + * + * This function assumes that the restart page header and the restart area have + * already been consistency checked. + * + * Unlike ntfs_check_restart_page_header() and ntfs_check_restart_area(), this + * function needs @rp->system_page_size bytes in @rp, i.e. it requires the full + * restart page and the page must be multi sector transfer deprotected. + */ +static BOOL ntfs_check_log_client_array(RESTART_PAGE_HEADER *rp) +{ + RESTART_AREA *ra; + LOG_CLIENT_RECORD *ca, *cr; + u16 nr_clients, idx; + BOOL in_free_list, idx_is_first; + + ntfs_debug("Entering."); + ra = (RESTART_AREA*)((u8*)rp + le16_to_cpu(rp->restart_area_offset)); + ca = (LOG_CLIENT_RECORD*)((u8*)ra + + le16_to_cpu(ra->client_array_offset)); + /* + * Check the ra->client_free_list first and then check the + * ra->client_in_use_list. Check each of the log client records in + * each of the lists and check that the array does not overflow the + * ra->log_clients value. Also keep track of the number of records + * visited as there cannot be more than ra->log_clients records and + * that way we detect eventual loops in within a list. + */ + nr_clients = le16_to_cpu(ra->log_clients); + idx = le16_to_cpu(ra->client_free_list); + in_free_list = TRUE; +check_list: + for (idx_is_first = TRUE; idx != LOGFILE_NO_CLIENT_CPU; nr_clients--, + idx = le16_to_cpu(cr->next_client)) { + if (!nr_clients || idx >= le16_to_cpu(ra->log_clients)) + goto err_out; + /* Set @cr to the current log client record. */ + cr = ca + idx; + /* The first log client record must not have a prev_client. */ + if (idx_is_first) { + if (cr->prev_client != LOGFILE_NO_CLIENT) + goto err_out; + idx_is_first = FALSE; + } + } + /* Switch to and check the in use list if we just did the free list. */ + if (in_free_list) { + in_free_list = FALSE; + idx = le16_to_cpu(ra->client_in_use_list); + goto check_list; + } + ntfs_debug("Done."); + return TRUE; +err_out: + ntfs_error(vi->i_sb, "$LogFile log client array is corrupt."); + return FALSE; +} + +/** + * ntfs_check_and_load_restart_page - check the restart page for consistency + * @log_na: opened ntfs attribute for journal $LogFile + * @rp: restart page to check + * @pos: position in @log_na at which the restart page resides + * @wrp: copy of the multi sector transfer deprotected restart page + * + * Check the restart page @rp for consistency and return TRUE if it is + * consistent and FALSE otherwise. + * + * This function only needs NTFS_BLOCK_SIZE bytes in @rp, i.e. it does not + * require the full restart page. + * + * If @wrp is not NULL, on success, *@wrp will point to a buffer containing a + * copy of the complete multi sector transfer deprotected page. On failure, + * *@wrp is undefined. + */ +static BOOL ntfs_check_and_load_restart_page(ntfs_attr *log_na, + RESTART_PAGE_HEADER *rp, s64 pos, RESTART_PAGE_HEADER **wrp) +{ + RESTART_AREA *ra; + RESTART_PAGE_HEADER *trp; + BOOL ret; + + ntfs_debug("Entering."); + /* Check the restart page header for consistency. */ + if (!ntfs_check_restart_page_header(rp, pos)) { + /* Error output already done inside the function. */ + return FALSE; + } + /* Check the restart area for consistency. */ + if (!ntfs_check_restart_area(rp)) { + /* Error output already done inside the function. */ + return FALSE; + } + ra = (RESTART_AREA*)((u8*)rp + le16_to_cpu(rp->restart_area_offset)); + /* + * Allocate a buffer to store the whole restart page so we can multi + * sector transfer deprotect it. + */ + trp = malloc(le32_to_cpu(rp->system_page_size)); + if (!trp) { + ntfs_error(vi->i_sb, "Failed to allocate memory for $LogFile " + "restart page buffer."); + return FALSE; + } + /* + * Read the whole of the restart page into the buffer. If it fits + * completely inside @rp, just copy it from there. Otherwise read it + * from disk. + */ + if (le32_to_cpu(rp->system_page_size) <= NTFS_BLOCK_SIZE) + memcpy(trp, rp, le32_to_cpu(rp->system_page_size)); + else + if (ntfs_attr_pread(log_na, pos, le32_to_cpu( + rp->system_page_size), trp) != + le32_to_cpu(rp->system_page_size)) { + ntfs_error(, "Failed to read whole restart page into " + "the buffer."); + goto err_out; + } + /* Perform the multi sector transfer deprotection on the buffer. */ + if (ntfs_mst_post_read_fixup((NTFS_RECORD*)trp, + le32_to_cpu(rp->system_page_size))) { + ntfs_error(vi->i_sb, "Multi sector transfer error detected in " + "$LogFile restart page."); + goto err_out; + } + /* Check the log client records for consistency. */ + ret = ntfs_check_log_client_array(trp); + if (ret && wrp) + *wrp = trp; + else + free(trp); + ntfs_debug("Done."); + return ret; +err_out: + free(trp); + return FALSE; +} + +/** + * ntfs_ckeck_logfile - check in the journal if the volume is consistent + * @log_na: ntfs attribute of loaded journal $LogFile to check + * + * Check the $LogFile journal for consistency and return TRUE if it is + * consistent and FALSE if not. + * + * At present we only check the two restart pages and ignore the log record + * pages. + * + * Note that the MstProtected flag is not set on the $LogFile inode and hence + * when reading pages they are not deprotected. This is because we do not know + * if the $LogFile was created on a system with a different page size to ours + * yet and mst deprotection would fail if our page size is smaller. + */ +BOOL ntfs_check_logfile(ntfs_attr *log_na) +{ + s64 size, pos, rstr1_pos, rstr2_pos; + ntfs_volume *vol = log_na->ni->vol; + u8 *buf = NULL; + RESTART_PAGE_HEADER *rstr1_ph = NULL; + RESTART_PAGE_HEADER *rstr2_ph = NULL; + int log_page_size, log_page_mask, ofs; + BOOL logfile_is_empty = TRUE; + BOOL rstr1_found = FALSE; + BOOL rstr2_found = FALSE; + u8 log_page_bits; + + ntfs_debug("Entering."); + /* An empty $LogFile must have been clean before it got emptied. */ + if (NVolLogFileEmpty(vol)) + goto is_empty; + size = log_na->data_size; + /* Make sure the file doesn't exceed the maximum allowed size. */ + if (size > (s64)MaxLogFileSize) + size = MaxLogFileSize; + log_page_size = DefaultLogPageSize; + log_page_mask = log_page_size - 1; + /* + * Use generic_ffs() instead of ffs() to enable the compiler to + * optimize log_page_size and log_page_bits into constants. + */ + log_page_bits = ffs(log_page_size) - 1; + size &= ~(log_page_size - 1); + + /* + * Ensure the log file is big enough to store at least the two restart + * pages and the minimum number of log record pages. + */ + if (size < log_page_size * 2 || (size - log_page_size * 2) >> + log_page_bits < MinLogRecordPages) { + ntfs_error(vol->sb, "$LogFile is too small."); + return FALSE; + } + /* Allocate memory for restart page. */ + buf = malloc(NTFS_BLOCK_SIZE); + if (!buf) { + ntfs_error(, "Not enough memory."); + return FALSE; + } + /* + * Read through the file looking for a restart page. Since the restart + * page header is at the beginning of a page we only need to search at + * what could be the beginning of a page (for each page size) rather + * than scanning the whole file byte by byte. If all potential places + * contain empty and uninitialzed records, the log file can be assumed + * to be empty. + */ + for (pos = 0; pos < size; pos <<= 1) { + /* + * Read first NTFS_BLOCK_SIZE bytes of potential restart page. + */ + if (ntfs_attr_pread(log_na, pos, NTFS_BLOCK_SIZE, buf) != + NTFS_BLOCK_SIZE) { + ntfs_error(, "Failed to read first NTFS_BLOCK_SIZE " + "bytes of potential restart page."); + goto err_out; + } + + /* + * A non-empty block means the logfile is not empty while an + * empty block after a non-empty block has been encountered + * means we are done. + */ + if (!ntfs_is_empty_recordp((le32*)buf)) + logfile_is_empty = FALSE; + else if (!logfile_is_empty) + break; + /* + * A log record page means there cannot be a restart page after + * this so no need to continue searching. + */ + if (ntfs_is_rcrd_recordp((le32*)buf)) + break; + /* + * A modified by chkdsk restart page means we cannot handle + * this log file. + */ + if (ntfs_is_chkd_recordp((le32*)buf)) { + ntfs_error(vol->sb, "$LogFile has been modified by " + "chkdsk. Mount this volume in " + "Windows."); + goto err_out; + } + /* If not a restart page, continue. */ + if (!ntfs_is_rstr_recordp((le32*)buf)) { + /* Skip to the minimum page size for the next one. */ + if (!pos) + pos = NTFS_BLOCK_SIZE >> 1; + continue; + } + /* We now know we have a restart page. */ + if (!pos) { + rstr1_found = TRUE; + rstr1_pos = pos; + } else { + if (rstr2_found) { + ntfs_error(vol->sb, "Found more than two " + "restart pages in $LogFile."); + goto err_out; + } + rstr2_found = TRUE; + rstr2_pos = pos; + } + /* + * Check the restart page for consistency and get a copy of the + * complete multi sector transfer deprotected restart page. + */ + if (!ntfs_check_and_load_restart_page(log_na, + (RESTART_PAGE_HEADER*)buf, pos, + !pos ? &rstr1_ph : &rstr2_ph)) { + /* Error output already done inside the function. */ + goto err_out; + } + /* + * We have a valid restart page. The next one must be after + * a whole system page size as specified by the valid restart + * page. + */ + if (!pos) + pos = le32_to_cpu(rstr1_ph->system_page_size) >> 1; + } + if (buf) { + free(buf); + buf = NULL; + } + if (logfile_is_empty) { + NVolSetLogFileEmpty(vol); +is_empty: + ntfs_debug("Done. ($LogFile is empty.)"); + return TRUE; + } + if (!rstr1_found || !rstr2_found) { + ntfs_error(vol->sb, "Did not find two restart pages in " + "$LogFile."); + goto err_out; + } + /* + * The two restart areas must be identical except for the update + * sequence number. + */ + ofs = le16_to_cpu(rstr1_ph->usa_ofs); + if (memcmp(rstr1_ph, rstr2_ph, ofs) || (ofs += sizeof(u16), + memcmp((u8*)rstr1_ph + ofs, (u8*)rstr2_ph + ofs, + le32_to_cpu(rstr1_ph->system_page_size) - ofs))) { + ntfs_error(vol->sb, "The two restart pages in $LogFile do not " + "match."); + goto err_out; + } + free(rstr1_ph); + free(rstr2_ph); + /* All consistency checks passed. */ + ntfs_debug("Done."); + return TRUE; +err_out: + if (buf) + free(buf); + if (rstr1_ph) + free(rstr1_ph); + if (rstr2_ph) + free(rstr2_ph); + return FALSE; +} + +/** + * ntfs_is_logfile_clean - check in the journal if the volume is clean + * @log_na: ntfs attribute of loaded journal $LogFile to check + * + * Analyze the $LogFile journal and return TRUE if it indicates the volume was + * shutdown cleanly and FALSE if not. + * + * At present we only look at the two restart pages and ignore the log record + * pages. This is a little bit crude in that there will be a very small number + * of cases where we think that a volume is dirty when in fact it is clean. + * This should only affect volumes that have not been shutdown cleanly but did + * not have any pending, non-check-pointed i/o, i.e. they were completely idle + * at least for the five seconds preceeding the unclean shutdown. + * + * This function assumes that the $LogFile journal has already been consistency + * checked by a call to ntfs_check_logfile() and in particular if the $LogFile + * is empty this function requires that NVolLogFileEmpty() is true otherwise an + * empty volume will be reported as dirty. + */ +BOOL ntfs_is_logfile_clean(ntfs_attr *log_na) +{ + RESTART_PAGE_HEADER *rp; + RESTART_AREA *ra; + + ntfs_debug("Entering."); + /* An empty $LogFile must have been clean before it got emptied. */ + if (NVolLogFileEmpty(log_na->ni->vol)) { + ntfs_debug("Done. ($LogFile is empty.)"); + return TRUE; + } + /* Allocate memory. */ + rp = malloc(NTFS_BLOCK_SIZE); + if (!rp) { + ntfs_error(, "Not enough memory."); + return FALSE; + } + /* + * Read the first restart page. It will be possibly incomplete and + * will not be multi sector transfer deprotected but we only need the + * first NTFS_BLOCK_SIZE bytes so it does not matter. + */ + if (ntfs_attr_pread(log_na, 0, NTFS_BLOCK_SIZE, rp) != + NTFS_BLOCK_SIZE) { + ntfs_error(, "Failed to read first restart page."); + goto err_out; + } + if (!ntfs_is_rstr_record(rp->magic)) { + ntfs_error(vol->sb, "No restart page found at offset zero in " + "$LogFile. This is probably a bug in that " + "the $LogFile should have been consistency " + "checked before calling this function."); + goto err_out; + } + ra = (RESTART_AREA*)((u8*)rp + le16_to_cpu(rp->restart_area_offset)); + /* + * If the $LogFile has active clients, i.e. it is open, and we do not + * have the RESTART_VOLUME_IS_CLEAN bit set in the restart area flags, + * we assume there was an unclean shutdown. + */ + if (ra->client_in_use_list != LOGFILE_NO_CLIENT && + !(ra->flags & RESTART_VOLUME_IS_CLEAN)) { + ntfs_debug("Done. $LogFile indicates a dirty shutdown."); + goto err_out; + } + free(rp); + /* $LogFile indicates a clean shutdown. */ + ntfs_debug("Done. $LogFile indicates a clean shutdown."); + return TRUE; +err_out: + free(rp); + return FALSE; +} + +/** + * ntfs_empty_logfile - empty the contents of the $LogFile journal + * @na: ntfs attribute of journal $LogFile to empty + * + * Empty the contents of the $LogFile journal @na and return 0 on success and + * -1 on error. + * + * This function assumes that the $LogFile journal has already been consistency + * checked by a call to ntfs_check_logfile() and that ntfs_is_logfile_clean() + * has been used to ensure that the $LogFile is clean. + */ +int ntfs_empty_logfile(ntfs_attr *na) +{ + s64 len, pos, count; + char buf[NTFS_BUF_SIZE]; + int err; + + ntfs_debug("Entering."); + if (NVolLogFileEmpty(na->ni->vol)) + goto done; + + /* The $DATA attribute of the $LogFile has to be non-resident. */ + if (!NAttrNonResident(na)) { + err = EIO; + Dprintf("$LogFile $DATA attribute is resident!?!\n"); + goto io_error_exit; + } + + /* Get length of $LogFile contents. */ + len = na->data_size; + if (!len) { + Dprintf("$LogFile has zero length, no disk write needed.\n"); + return 0; + } + + /* Read $LogFile until its end. We do this as a check for correct + length thus making sure we are decompressing the mapping pairs + array correctly and hence writing below is safe as well. */ + pos = 0; + while ((count = ntfs_attr_pread(na, pos, NTFS_BUF_SIZE, buf)) > 0) + pos += count; + + if (count == -1 || pos != len) { + err = errno; + Dprintf("Amount of $LogFile data read does not " + "correspond to expected length!"); + if (count != -1) + err = EIO; + goto io_error_exit; + } + + /* Fill the buffer with 0xff's. */ + memset(buf, -1, NTFS_BUF_SIZE); + + /* Set the $DATA attribute. */ + pos = 0; + while ((count = len - pos) > 0) { + if (count > NTFS_BUF_SIZE) + count = NTFS_BUF_SIZE; + + if ((count = ntfs_attr_pwrite(na, pos, count, buf)) <= 0) { + err = errno; + Dprintf("Failed to set the $LogFile attribute value."); + if (count != -1) + err = EIO; + goto io_error_exit; + } + pos += count; + } + + /* Set the flag so we do not have to do it again on remount. */ + NVolSetLogFileEmpty(na->ni->vol); +done: + ntfs_debug("Done."); + return 0; +io_error_exit: + ntfs_attr_close(na); + ntfs_inode_close(na->ni); + errno = err; + return -1; +}