1 files changed, 136 insertions, 115 deletions

diff --git a/fs/ntfs/logfile.c b/fs/ntfs/logfile.c
index 8edb8e20fb08..0173e95500d9 100644
--- a/fs/ntfs/logfile.c
+++ b/fs/ntfs/logfile.c
@@ -121,7 +121,7 @@ static BOOL ntfs_check_restart_page_header(struct inode *vi,
          */
         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.");
+                                "by chkdsk but a chkdsk LSN is specified.");
                 return FALSE;
         }
         ntfs_debug("Done.");
@@ -312,10 +312,12 @@ err_out:
  * @vi:         $LogFile inode to which the restart page belongs
  * @rp:         restart page to check
  * @pos:        position in @vi at which the restart page resides
- * @wrp:        copy of the multi sector transfer deprotected restart page
+ * @wrp:        [OUT] copy of the multi sector transfer deprotected restart page
+ * @lsn:        [OUT] set to the current logfile lsn on success
  *
- * Check the restart page @rp for consistency and return TRUE if it is
- * consistent and FALSE otherwise.
+ * Check the restart page @rp for consistency and return 0 if it is consistent
+ * and -errno otherwise.  The restart page may have been modified by chkdsk in
+ * which case its magic is CHKD instead of RSTR.
  *
  * This function only needs NTFS_BLOCK_SIZE bytes in @rp, i.e. it does not
  * require the full restart page.
@@ -323,25 +325,33 @@ err_out:
  * 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.
+ *
+ * Simillarly, if @lsn is not NULL, on succes *@lsn will be set to the current
+ * logfile lsn according to this restart page.  On failure, *@lsn is undefined.
+ *
+ * The following error codes are defined:
+ *      -EINVAL - The restart page is inconsistent.
+ *      -ENOMEM - Not enough memory to load the restart page.
+ *      -EIO    - Failed to reading from $LogFile.
  */
-static BOOL ntfs_check_and_load_restart_page(struct inode *vi,
-                RESTART_PAGE_HEADER *rp, s64 pos, RESTART_PAGE_HEADER **wrp)
+static int ntfs_check_and_load_restart_page(struct inode *vi,
+                RESTART_PAGE_HEADER *rp, s64 pos, RESTART_PAGE_HEADER **wrp,
+                LSN *lsn)
 {
         RESTART_AREA *ra;
         RESTART_PAGE_HEADER *trp;
-        int size;
-        BOOL ret;
+        int size, err;
 
         ntfs_debug("Entering.");
         /* Check the restart page header for consistency. */
         if (!ntfs_check_restart_page_header(vi, rp, pos)) {
                 /* Error output already done inside the function. */
-                return FALSE;
+                return -EINVAL;
         }
         /* Check the restart area for consistency. */
         if (!ntfs_check_restart_area(vi, rp)) {
                 /* Error output already done inside the function. */
-                return FALSE;
+                return -EINVAL;
         }
         ra = (RESTART_AREA*)((u8*)rp + le16_to_cpu(rp->restart_area_offset));
         /*
@@ -352,7 +362,7 @@ static BOOL ntfs_check_and_load_restart_page(struct inode *vi,
         if (!trp) {
                 ntfs_error(vi->i_sb, "Failed to allocate memory for $LogFile "
                                 "restart page buffer.");
-                return FALSE;
+                return -ENOMEM;
         }
         /*
          * Read the whole of the restart page into the buffer.  If it fits
@@ -379,6 +389,9 @@ static BOOL ntfs_check_and_load_restart_page(struct inode *vi,
                         if (IS_ERR(page)) {
                                 ntfs_error(vi->i_sb, "Error mapping $LogFile "
                                                 "page (index %lu).", idx);
+                                err = PTR_ERR(page);
+                                if (err != -EIO && err != -ENOMEM)
+                                        err = -EIO;
                                 goto err_out;
                         }
                         size = min_t(int, to_read, PAGE_CACHE_SIZE);
@@ -392,29 +405,57 @@ static BOOL ntfs_check_and_load_restart_page(struct inode *vi,
         /* Perform the multi sector transfer deprotection on the buffer. */
         if (post_read_mst_fixup((NTFS_RECORD*)trp,
                         le32_to_cpu(rp->system_page_size))) {
-                ntfs_error(vi->i_sb, "Multi sector transfer error detected in "
-                                "$LogFile restart page.");
-                goto err_out;
+                /*
+                 * A multi sector tranfer error was detected.  We only need to
+                 * abort if the restart page contents exceed the multi sector
+                 * transfer fixup of the first sector.
+                 */
+                if (le16_to_cpu(rp->restart_area_offset) +
+                                le16_to_cpu(ra->restart_area_length) >
+                                NTFS_BLOCK_SIZE - sizeof(u16)) {
+                        ntfs_error(vi->i_sb, "Multi sector transfer error "
+                                        "detected in $LogFile restart page.");
+                        err = -EINVAL;
+                        goto err_out;
+                }
+        }
+        /*
+         * If the restart page is modified by chkdsk or there are no active
+         * logfile clients, the logfile is consistent.  Otherwise, need to
+         * check the log client records for consistency, too.
+         */
+        err = 0;
+        if (ntfs_is_rstr_record(rp->magic) &&
+                        ra->client_in_use_list != LOGFILE_NO_CLIENT) {
+                if (!ntfs_check_log_client_array(vi, trp)) {
+                        err = -EINVAL;
+                        goto err_out;
+                }
+        }
+        if (lsn) {
+                if (ntfs_is_rstr_record(rp->magic))
+                        *lsn = sle64_to_cpu(ra->current_lsn);
+                else /* if (ntfs_is_chkd_record(rp->magic)) */
+                        *lsn = sle64_to_cpu(rp->chkdsk_lsn);
         }
-        /* Check the log client records for consistency. */
-        ret = ntfs_check_log_client_array(vi, trp);
-        if (ret && wrp)
-                *wrp = trp;
-        else
-                ntfs_free(trp);
         ntfs_debug("Done.");
-        return ret;
+        if (wrp)
+                *wrp = trp;
+        else {
 err_out:
-        ntfs_free(trp);
-        return FALSE;
+                ntfs_free(trp);
+        }
+        return err;
 }
 
 /**
  * ntfs_check_logfile - check the journal for consistency
  * @log_vi:     struct inode of loaded journal $LogFile to check
+ * @rp:         [OUT] on success this is a copy of the current restart page
  *
  * Check the $LogFile journal for consistency and return TRUE if it is
- * consistent and FALSE if not.
+ * consistent and FALSE if not.  On success, the current restart page is
+ * returned in *@rp.  Caller must call ntfs_free(*@rp) when finished with it.
  *
  * At present we only check the two restart pages and ignore the log record
  * pages.
@@ -424,19 +465,18 @@ err_out:
  * 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(struct inode *log_vi)
+BOOL ntfs_check_logfile(struct inode *log_vi, RESTART_PAGE_HEADER **rp)
 {
-        s64 size, pos, rstr1_pos, rstr2_pos;
+        s64 size, pos;
+        LSN rstr1_lsn, rstr2_lsn;
         ntfs_volume *vol = NTFS_SB(log_vi->i_sb);
         struct address_space *mapping = log_vi->i_mapping;
         struct page *page = NULL;
         u8 *kaddr = NULL;
         RESTART_PAGE_HEADER *rstr1_ph = NULL;
         RESTART_PAGE_HEADER *rstr2_ph = NULL;
-        int log_page_size, log_page_mask, ofs;
+        int log_page_size, log_page_mask, err;
         BOOL logfile_is_empty = TRUE;
-        BOOL rstr1_found = FALSE;
-        BOOL rstr2_found = FALSE;
         u8 log_page_bits;
 
         ntfs_debug("Entering.");
@@ -491,7 +531,7 @@ BOOL ntfs_check_logfile(struct inode *log_vi)
                         if (IS_ERR(page)) {
                                 ntfs_error(vol->sb, "Error mapping $LogFile "
                                                 "page (index %lu).", idx);
-                                return FALSE;
+                                goto err_out;
                         }
                 }
                 kaddr = (u8*)page_address(page) + (pos & ~PAGE_CACHE_MASK);
@@ -510,99 +550,95 @@ BOOL ntfs_check_logfile(struct inode *log_vi)
                  */
                 if (ntfs_is_rcrd_recordp((le32*)kaddr))
                         break;
-                /*
-                 * A modified by chkdsk restart page means we cannot handle
-                 * this log file.
-                 */
-                if (ntfs_is_chkd_recordp((le32*)kaddr)) {
-                        ntfs_error(vol->sb, "$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*)kaddr)) {
-                        /* Skip to the minimum page size for the next one. */
+                /* If not a (modified by chkdsk) restart page, continue. */
+                if (!ntfs_is_rstr_recordp((le32*)kaddr) &&
+                                !ntfs_is_chkd_recordp((le32*)kaddr)) {
                         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.
+                 * Check the (modified by chkdsk) 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_vi,
+                err = ntfs_check_and_load_restart_page(log_vi,
                                 (RESTART_PAGE_HEADER*)kaddr, pos,
-                                !pos ? &rstr1_ph : &rstr2_ph)) {
-                        /* Error output already done inside the function. */
-                        goto err_out;
+                                !rstr1_ph ? &rstr1_ph : &rstr2_ph,
+                                !rstr1_ph ? &rstr1_lsn : &rstr2_lsn);
+                if (!err) {
+                        /*
+                         * If we have now found the first (modified by chkdsk)
+                         * restart page, continue looking for the second one.
+                         */
+                        if (!pos) {
+                                pos = NTFS_BLOCK_SIZE >> 1;
+                                continue;
+                        }
+                        /*
+                         * We have now found the second (modified by chkdsk)
+                         * restart page, so we can stop looking.
+                         */
+                        break;
                 }
                 /*
-                 * We have a valid restart page.  The next one must be after
-                 * a whole system page size as specified by the valid restart
-                 * page.
+                 * Error output already done inside the function.  Note, we do
+                 * not abort if the restart page was invalid as we might still
+                 * find a valid one further in the file.
                  */
+                if (err != -EINVAL) {
+                        ntfs_unmap_page(page);
+                        goto err_out;
+                }
+                /* Continue looking. */
                 if (!pos)
-                        pos = le32_to_cpu(rstr1_ph->system_page_size) >> 1;
+                        pos = NTFS_BLOCK_SIZE >> 1;
         }
-        if (page) {
+        if (page)
                 ntfs_unmap_page(page);
-                page = 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 "
-                                "$LogFile.");
-                goto err_out;
+        if (!rstr1_ph) {
+                BUG_ON(rstr2_ph);
+                ntfs_error(vol->sb, "Did not find any restart pages in "
+                                "$LogFile and it was not empty.");
+                return FALSE;
+        }
+        /* If both restart pages were found, use the more recent one. */
+        if (rstr2_ph) {
+                /*
+                 * If the second restart area is more recent, switch to it.
+                 * Otherwise just throw it away.
+                 */
+                if (rstr2_lsn > rstr1_lsn) {
+                        ntfs_free(rstr1_ph);
+                        rstr1_ph = rstr2_ph;
+                        /* rstr1_lsn = rstr2_lsn; */
+                } else
+                        ntfs_free(rstr2_ph);
+                rstr2_ph = NULL;
         }
-        /*
-         * 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;
-        }
-        ntfs_free(rstr1_ph);
-        ntfs_free(rstr2_ph);
         /* All consistency checks passed. */
+        if (rp)
+                *rp = rstr1_ph;
+        else
+                ntfs_free(rstr1_ph);
         ntfs_debug("Done.");
         return TRUE;
 err_out:
-        if (page)
-                ntfs_unmap_page(page);
         if (rstr1_ph)
                 ntfs_free(rstr1_ph);
-        if (rstr2_ph)
-                ntfs_free(rstr2_ph);
         return FALSE;
 }
 
 /**
  * ntfs_is_logfile_clean - check in the journal if the volume is clean
  * @log_vi:     struct inode of loaded journal $LogFile to check
+ * @rp:         copy of the current restart page
  *
  * Analyze the $LogFile journal and return TRUE if it indicates the volume was
  * shutdown cleanly and FALSE if not.
@@ -619,11 +655,9 @@ err_out:
  * is empty this function requires that NVolLogFileEmpty() is true otherwise an
  * empty volume will be reported as dirty.
  */
-BOOL ntfs_is_logfile_clean(struct inode *log_vi)
+BOOL ntfs_is_logfile_clean(struct inode *log_vi, const RESTART_PAGE_HEADER *rp)
 {
         ntfs_volume *vol = NTFS_SB(log_vi->i_sb);
-        struct page *page;
-        RESTART_PAGE_HEADER *rp;
         RESTART_AREA *ra;
 
         ntfs_debug("Entering.");
@@ -632,24 +666,15 @@ BOOL ntfs_is_logfile_clean(struct inode *log_vi)
                 ntfs_debug("Done.  ($LogFile is empty.)");
                 return TRUE;
         }
-        /*
-         * 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.
-         */
-        page = ntfs_map_page(log_vi->i_mapping, 0);
-        if (IS_ERR(page)) {
-                ntfs_error(vol->sb, "Error mapping $LogFile page (index 0).");
+        BUG_ON(!rp);
+        if (!ntfs_is_rstr_record(rp->magic) &&
+                        !ntfs_is_chkd_record(rp->magic)) {
+                ntfs_error(vol->sb, "Restart page buffer is invalid.  This is "
+                                "probably a bug in that the $LogFile should "
+                                "have been consistency checked before calling "
+                                "this function.");
                 return FALSE;
         }
-        rp = (RESTART_PAGE_HEADER*)page_address(page);
-        if (!ntfs_is_rstr_record(rp->magic)) {
-                ntfs_error(vol->sb, "No restart page found at offset zero in "
-                                "$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
@@ -659,15 +684,11 @@ BOOL ntfs_is_logfile_clean(struct inode *log_vi)
         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;
+                return FALSE;
         }
-        ntfs_unmap_page(page);
         /* $LogFile indicates a clean shutdown. */
         ntfs_debug("Done.  $LogFile indicates a clean shutdown.");
         return TRUE;
-err_out:
-        ntfs_unmap_page(page);
-        return FALSE;
 }
 
 /**