fs/ntfs3: fix mount failure on 64K page-size kernels

On 64K page-size kernels, mounting NTFS volumes smaller than ~650 MB
fails with EINVAL. The issue is in log_replay(): the initial log page
size probe uses PAGE_SIZE (65536) instead of DefaultLogPageSize (4096)
when PAGE_SIZE exceeds DefaultLogPageSize * 2.

This makes norm_file_page() require the $LogFile to be at least
50 * 65536 = 3.2 MB, but mkfs.ntfs creates a $LogFile of only ~1.5 MB
for a typical 300 MB volume. norm_file_page() returns 0 and the mount
is rejected with EINVAL.

On 4K kernels the #if guard evaluates to true, so use_default=true is
passed and DefaultLogPageSize (4096) is used, requiring only ~200 KB.
This path works fine.

Fix this by always passing use_default=true, which forces the initial
probe to use DefaultLogPageSize regardless of the kernel's PAGE_SIZE.
This is safe because, after reading the on-disk restart area, log_replay()
already re-adjusts log->page_size to match the volume's actual
sys_page_size.

Also fix read_log_page() to pass log->page_size instead of PAGE_SIZE to
ntfs_fix_post_read(), matching the actual buffer size.

Fixes: b46acd6a6a62 ("fs/ntfs3: Add NTFS journal")
Tested-by: Matthew R. Ochs <mochs@nvidia.com>
Signed-off-by: Jamie Nguyen <jamien@nvidia.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

diff --git a/fs/ntfs3/fslog.c b/fs/ntfs3/fslog.c
index 767f7cdab8d15c78adb7b8856f6cd29bd0e23478..92a7e3a462406a562f4ed9091230c16a66ffe3e3 100644 (file)
--- a/fs/ntfs3/fslog.c
+++ b/fs/ntfs3/fslog.c
@@ -1172,7 +1172,7 @@ static int read_log_page(struct ntfs_log *log, u32 vbo,
                goto out;
 
        if (page_buf->rhdr.sign != NTFS_FFFF_SIGNATURE)
-               ntfs_fix_post_read(&page_buf->rhdr, PAGE_SIZE, false);
+               ntfs_fix_post_read(&page_buf->rhdr, log->page_size, false);
 
        if (page_buf != *buffer)
                memcpy(*buffer, Add2Ptr(page_buf, page_off), bytes);
@@ -3813,11 +3813,7 @@ int log_replay(struct ntfs_inode *ni, bool *initialized)
        log->l_size = log->orig_file_size = ni->vfs_inode.i_size;
 
        /* Get the size of page. NOTE: To replay we can use default page. */
-#if PAGE_SIZE >= DefaultLogPageSize && PAGE_SIZE <= DefaultLogPageSize * 2
        log->page_size = norm_file_page(PAGE_SIZE, &log->l_size, true);
-#else
-       log->page_size = norm_file_page(PAGE_SIZE, &log->l_size, false);
-#endif
        if (!log->page_size) {
                err = -EINVAL;
                goto out;