1 files changed, 88 insertions, 67 deletions

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 8f4f079e6b9a..a6b1ab734728 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -45,6 +45,7 @@
 #include "ext4_jbd2.h"
 #include "xattr.h"
 #include "acl.h"
+#include "mballoc.h"
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/ext4.h>
@@ -344,7 +345,8 @@ static const char *ext4_decode_error(struct super_block *sb, int errno,
                 errstr = "Out of memory";
                 break;
         case -EROFS:
-                if (!sb || EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT)
+                if (!sb || (EXT4_SB(sb)->s_journal &&
+                            EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
                         errstr = "Journal has aborted";
                 else
                         errstr = "Readonly filesystem";
@@ -1279,11 +1281,9 @@ static int parse_options(char *options, struct super_block *sb,
                         *journal_devnum = option;
                         break;
                 case Opt_journal_checksum:
-                        set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
-                        break;
+                        break;  /* Kept for backwards compatibility */
                 case Opt_journal_async_commit:
                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
-                        set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
                         break;
                 case Opt_noload:
                         set_opt(sbi->s_mount_opt, NOLOAD);
@@ -1695,12 +1695,12 @@ static int ext4_fill_flex_info(struct super_block *sb)
                 gdp = ext4_get_group_desc(sb, i, NULL);
 
                 flex_group = ext4_flex_group(sbi, i);
-                atomic_set(&sbi->s_flex_groups[flex_group].free_inodes,
-                           ext4_free_inodes_count(sb, gdp));
-                atomic_set(&sbi->s_flex_groups[flex_group].free_blocks,
-                           ext4_free_blks_count(sb, gdp));
-                atomic_set(&sbi->s_flex_groups[flex_group].used_dirs,
-                           ext4_used_dirs_count(sb, gdp));
+                atomic_add(ext4_free_inodes_count(sb, gdp),
+                           &sbi->s_flex_groups[flex_group].free_inodes);
+                atomic_add(ext4_free_blks_count(sb, gdp),
+                           &sbi->s_flex_groups[flex_group].free_blocks);
+                atomic_add(ext4_used_dirs_count(sb, gdp),
+                           &sbi->s_flex_groups[flex_group].used_dirs);
         }
 
         return 1;
@@ -2253,6 +2253,49 @@ static struct kobj_type ext4_ktype = {
         .release        = ext4_sb_release,
 };
 
+/*
+ * Check whether this filesystem can be mounted based on
+ * the features present and the RDONLY/RDWR mount requested.
+ * Returns 1 if this filesystem can be mounted as requested,
+ * 0 if it cannot be.
+ */
+static int ext4_feature_set_ok(struct super_block *sb, int readonly)
+{
+        if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
+                ext4_msg(sb, KERN_ERR,
+                        "Couldn't mount because of "
+                        "unsupported optional features (%x)",
+                        (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
+                        ~EXT4_FEATURE_INCOMPAT_SUPP));
+                return 0;
+        }
+
+        if (readonly)
+                return 1;
+
+        /* Check that feature set is OK for a read-write mount */
+        if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
+                ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
+                         "unsupported optional features (%x)",
+                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
+                                ~EXT4_FEATURE_RO_COMPAT_SUPP));
+                return 0;
+        }
+        /*
+         * Large file size enabled file system can only be mounted
+         * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
+         */
+        if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
+                if (sizeof(blkcnt_t) < sizeof(u64)) {
+                        ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
+                                 "cannot be mounted RDWR without "
+                                 "CONFIG_LBDAF");
+                        return 0;
+                }
+        }
+        return 1;
+}
+
 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
                                 __releases(kernel_lock)
                                 __acquires(kernel_lock)
@@ -2274,7 +2317,6 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
         unsigned int db_count;
         unsigned int i;
         int needs_recovery, has_huge_files;
-        int features;
         __u64 blocks_count;
         int err;
         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
@@ -2401,39 +2443,9 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
          * previously didn't change the revision level when setting the flags,
          * so there is a chance incompat flags are set on a rev 0 filesystem.
          */
-        features = EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP);
-        if (features) {
-                ext4_msg(sb, KERN_ERR,
-                        "Couldn't mount because of "
-                        "unsupported optional features (%x)",
-                        (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
-                        ~EXT4_FEATURE_INCOMPAT_SUPP));
-                goto failed_mount;
-        }
-        features = EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP);
-        if (!(sb->s_flags & MS_RDONLY) && features) {
-                ext4_msg(sb, KERN_ERR,
-                        "Couldn't mount RDWR because of "
-                        "unsupported optional features (%x)",
-                        (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
-                        ~EXT4_FEATURE_RO_COMPAT_SUPP));
+        if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
                 goto failed_mount;
-        }
-        has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
-                                    EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
-        if (has_huge_files) {
-                /*
-                 * Large file size enabled file system can only be
-                 * mount if kernel is build with CONFIG_LBDAF
-                 */
-                if (sizeof(root->i_blocks) < sizeof(u64) &&
-                                !(sb->s_flags & MS_RDONLY)) {
-                        ext4_msg(sb, KERN_ERR, "Filesystem with huge "
-                                        "files cannot be mounted read-write "
-                                        "without CONFIG_LBDAF");
-                        goto failed_mount;
-                }
-        }
+
         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
 
         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
@@ -2469,6 +2481,8 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
                 }
         }
 
+        has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
+                                EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
                                                       has_huge_files);
         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
@@ -2549,12 +2563,19 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
                 goto failed_mount;
         }
 
-        if (ext4_blocks_count(es) >
-                    (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) {
+        /*
+         * Test whether we have more sectors than will fit in sector_t,
+         * and whether the max offset is addressable by the page cache.
+         */
+        if ((ext4_blocks_count(es) >
+             (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) ||
+            (ext4_blocks_count(es) >
+             (pgoff_t)(~0ULL) >> (PAGE_CACHE_SHIFT - sb->s_blocksize_bits))) {
                 ext4_msg(sb, KERN_ERR, "filesystem"
-                        " too large to mount safely");
+                         " too large to mount safely on this system");
                 if (sizeof(sector_t) < 8)
                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
+                ret = -EFBIG;
                 goto failed_mount;
         }
 
@@ -2595,6 +2616,8 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
                 goto failed_mount;
         }
         sbi->s_groups_count = blocks_count;
+        sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
+                        (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
                    EXT4_DESC_PER_BLOCK(sb);
         sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
@@ -2729,20 +2752,14 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
                 goto failed_mount4;
         }
 
-        if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
-                jbd2_journal_set_features(sbi->s_journal,
-                                JBD2_FEATURE_COMPAT_CHECKSUM, 0,
+        jbd2_journal_set_features(sbi->s_journal,
+                                  JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
+        if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
+                jbd2_journal_set_features(sbi->s_journal, 0, 0,
                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
-        } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
-                jbd2_journal_set_features(sbi->s_journal,
-                                JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
+        else
                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
-        } else {
-                jbd2_journal_clear_features(sbi->s_journal,
-                                JBD2_FEATURE_COMPAT_CHECKSUM, 0,
-                                JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
-        }
 
         /* We have now updated the journal if required, so we can
          * validate the data journaling mode. */
@@ -3208,7 +3225,18 @@ static int ext4_commit_super(struct super_block *sb, int sync)
                 clear_buffer_write_io_error(sbh);
                 set_buffer_uptodate(sbh);
         }
-        es->s_wtime = cpu_to_le32(get_seconds());
+        /*
+         * If the file system is mounted read-only, don't update the
+         * superblock write time.  This avoids updating the superblock
+         * write time when we are mounting the root file system
+         * read/only but we need to replay the journal; at that point,
+         * for people who are east of GMT and who make their clock
+         * tick in localtime for Windows bug-for-bug compatibility,
+         * the clock is set in the future, and this will cause e2fsck
+         * to complain and force a full file system check.
+         */
+        if (!(sb->s_flags & MS_RDONLY))
+                es->s_wtime = cpu_to_le32(get_seconds());
         es->s_kbytes_written =
                 cpu_to_le64(EXT4_SB(sb)->s_kbytes_written + 
                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
@@ -3477,18 +3505,11 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data)
                         if (sbi->s_journal)
                                 ext4_mark_recovery_complete(sb, es);
                 } else {
-                        int ret;
-                        if ((ret = EXT4_HAS_RO_COMPAT_FEATURE(sb,
-                                        ~EXT4_FEATURE_RO_COMPAT_SUPP))) {
-                                ext4_msg(sb, KERN_WARNING, "couldn't "
-                                       "remount RDWR because of unsupported "
-                                       "optional features (%x)",
-                                (le32_to_cpu(sbi->s_es->s_feature_ro_compat) &
-                                        ~EXT4_FEATURE_RO_COMPAT_SUPP));
+                        /* Make sure we can mount this feature set readwrite */
+                        if (!ext4_feature_set_ok(sb, 0)) {
                                 err = -EROFS;
                                 goto restore_opts;
                         }
-
                         /*
                          * Make sure the group descriptor checksums
                          * are sane.  If they aren't, refuse to remount r/w.