[PATCH] ufs: one way to access super block
Super block of UFS usually has size >512, because of fragment size may be 512,
this cause some problems.
Currently, there are two methods to work with ufs super block:
1) split structure which describes ufs super blocks into structures with
size <=512
2) use one structure which describes ufs super block, and hope that array
of "buffer_head" which holds "super block", has such construction:
bh[n]->b_data + bh[n]->b_size == bh[n + 1]->b_data
The second variant may cause some problems in the future, and usage of two
variants cause unnecessary code duplication.
This patch remove the second variant. Also patch contains some CodingStyle
fixes.
Signed-off-by: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/ufs_fs.h b/include/linux/ufs_fs.h
index 28b3159..87b0a65 100644
--- a/include/linux/ufs_fs.h
+++ b/include/linux/ufs_fs.h
@@ -351,8 +351,12 @@
__fs64 cs_spare[3]; /* future expansion */
};
+#if 0
/*
* This is the actual superblock, as it is laid out on the disk.
+ * Do NOT use this structure, because of sizeof(ufs_super_block) > 512 and
+ * it may occupy several blocks, use
+ * struct ufs_super_block_(first,second,third) instead.
*/
struct ufs_super_block {
__fs32 fs_link; /* UNUSED */
@@ -498,6 +502,7 @@
__fs32 fs_magic; /* magic number */
__u8 fs_space[1]; /* list of blocks for each rotation */
};
+#endif/*struct ufs_super_block*/
/*
* Preference for optimization.
@@ -837,16 +842,54 @@
};
struct ufs_super_block_second {
- __s8 fs_fsmnt[212];
- __fs32 fs_cgrotor;
- __fs32 fs_csp[UFS_MAXCSBUFS];
- __fs32 fs_maxcluster;
- __fs32 fs_cpc;
- __fs16 fs_opostbl[82];
-};
+ union {
+ struct {
+ __s8 fs_fsmnt[212];
+ __fs32 fs_cgrotor;
+ __fs32 fs_csp[UFS_MAXCSBUFS];
+ __fs32 fs_maxcluster;
+ __fs32 fs_cpc;
+ __fs16 fs_opostbl[82];
+ } fs_u1;
+ struct {
+ __s8 fs_fsmnt[UFS2_MAXMNTLEN - UFS_MAXMNTLEN + 212];
+ __u8 fs_volname[UFS2_MAXVOLLEN];
+ __fs64 fs_swuid;
+ __fs32 fs_pad;
+ __fs32 fs_cgrotor;
+ __fs32 fs_ocsp[UFS2_NOCSPTRS];
+ __fs32 fs_contigdirs;
+ __fs32 fs_csp;
+ __fs32 fs_maxcluster;
+ __fs32 fs_active;
+ __fs32 fs_old_cpc;
+ __fs32 fs_maxbsize;
+ __fs64 fs_sparecon64[17];
+ __fs64 fs_sblockloc;
+ __fs64 cs_ndir;
+ __fs64 cs_nbfree;
+ } fs_u2;
+ } fs_un;
+};
struct ufs_super_block_third {
- __fs16 fs_opostbl[46];
+ union {
+ struct {
+ __fs16 fs_opostbl[46];
+ } fs_u1;
+ struct {
+ __fs64 cs_nifree; /* number of free inodes */
+ __fs64 cs_nffree; /* number of free frags */
+ __fs64 cs_numclusters; /* number of free clusters */
+ __fs64 cs_spare[3]; /* future expansion */
+ struct ufs_timeval fs_time; /* last time written */
+ __fs64 fs_size; /* number of blocks in fs */
+ __fs64 fs_dsize; /* number of data blocks in fs */
+ __fs64 fs_csaddr; /* blk addr of cyl grp summary area */
+ __fs64 fs_pendingblocks;/* blocks in process of being freed */
+ __fs32 fs_pendinginodes;/*inodes in process of being freed */
+ } fs_u2;
+ } fs_un1;
union {
struct {
__fs32 fs_sparecon[53];/* reserved for future constants */
@@ -874,7 +917,7 @@
__fs32 fs_qfmask[2]; /* ~usb_fmask */
__fs32 fs_state; /* file system state time stamp */
} fs_44;
- } fs_u2;
+ } fs_un2;
__fs32 fs_postblformat;
__fs32 fs_nrpos;
__fs32 fs_postbloff;