Add support for ns timestamps and birthtime to the ext2/3 driver.

When using big inodes there is sufficient space in ext3 to
keep extra resolution and birthtime (creation) timestamps.
The appropriate fields in the on-disk inode have been approved
for a long time but support for this in ext3 has not been
widely  distributed.

In preparation for ext4 most linux distributions have enabled
by default such bigger inodes and some people use nanosecond
timestamps in ext3. We now support those when the inode is big
enough and while we do recognize the EXT4F_ROCOMPAT_EXTRA_ISIZE,
we maintain the extra timestamps even when they are not used.

An additional note by Bruce Evans:
We blindly accept unrepresentable tv_nsec in VOP_SETATTR(), but
all file  systems have always done that.  When POSIX gets around
to  specifying the behaviour, it will probably require certain
rounding to the fs's resolution and not rejecting the request.
This unfortunately means that syscalls that set times can't
really tell if they succeeded without reading back the times
using stat() or similar and checking that they were set close
enough.

Reviewed by:	bde
Approved by:	jhb (mentor)
MFC after:	2 weeks

7 files changed, 74 insertions, 23 deletions

diff --git a/sys/fs/ext2fs/ext2_alloc.c b/sys/fs/ext2fs/ext2_alloc.c
index c834077..15d938c 100644
--- a/sys/fs/ext2fs/ext2_alloc.c
+++ b/sys/fs/ext2fs/ext2_alloc.c
@@ -344,6 +344,7 @@ ext2_valloc(pvp, mode, cred, vpp)
 	struct ucred *cred;
 	struct vnode **vpp;
 {
+	struct timespec ts;
 	struct inode *pip;
 	struct m_ext2fs *fs;
 	struct inode *ip;
@@ -385,14 +386,14 @@ ext2_valloc(pvp, mode, cred, vpp)
 	}
 	ip = VTOI(*vpp);
 
-	/* 
-	  the question is whether using VGET was such good idea at all -
-	  Linux doesn't read the old inode in when it's allocating a
-	  new one. I will set at least i_size & i_blocks the zero. 
-	*/ 
-	ip->i_mode = 0;
+	/*
+	 * The question is whether using VGET was such good idea at all:
+	 * Linux doesn't read the old inode in when it is allocating a
+	 * new one. I will set at least i_size and i_blocks to zero.
+	 */
 	ip->i_size = 0;
 	ip->i_blocks = 0;
+	ip->i_mode = 0;
 	ip->i_flags = 0;
         /* now we want to make sure that the block pointers are zeroed out */
         for (i = 0; i < NDADDR; i++)
@@ -406,6 +407,11 @@ ext2_valloc(pvp, mode, cred, vpp)
 	 */
 	if (ip->i_gen == 0 || ++ip->i_gen == 0)
 		ip->i_gen = random() / 2 + 1;
+
+	vfs_timestamp(&ts);
+	ip->i_birthtime = ts.tv_sec;
+	ip->i_birthnsec = ts.tv_nsec;
+
 /*
 printf("ext2_valloc: allocated inode %d\n", ino);
 */
diff --git a/sys/fs/ext2fs/ext2_dinode.h b/sys/fs/ext2fs/ext2_dinode.h
index 6893ccc..1a7bf2d 100755
--- a/sys/fs/ext2fs/ext2_dinode.h
+++ b/sys/fs/ext2fs/ext2_dinode.h
@@ -61,6 +61,16 @@
 #define EXT2_NODUMP		0x00000040	/* do not dump file */
 #define EXT2_NOATIME		0x00000080	/* do not update atime */
 
+/*
+ * Definitions for nanosecond timestamps.
+ * Ext3 inode versioning, 2006-12-13.
+ */
+#define EXT3_EPOCH_BITS	2
+#define EXT3_EPOCH_MASK	((1 << EXT3_EPOCH_BITS) - 1)
+#define EXT3_NSEC_MASK	(~0UL << EXT3_EPOCH_BITS)
+
+#define E2DI_HAS_XTIME(ip)	(EXT2_INODE_SIZE((ip)->i_e2fs) > \
+				    E2FS_REV0_INODE_SIZE)
 
 /*
  * Structure of an inode on the disk
@@ -77,7 +87,7 @@ struct ext2fs_dinode {
 	uint16_t	e2di_nlink;	/*  26: File link count */
 	uint32_t	e2di_nblock;	/*  28: Blocks count */
 	uint32_t	e2di_flags;	/*  32: Status flags (chflags) */
-	uint32_t	e2di_linux_reserved1; /* 36 */
+	uint32_t	e2di_version;	/*  36: Low 32 bits inode version */
 	uint32_t	e2di_blocks[EXT2_N_BLOCKS]; /* 40: disk blocks */
 	uint32_t	e2di_gen;	/* 100: generation number */
 	uint32_t	e2di_facl;	/* 104: file ACL (not implemented) */
@@ -91,6 +101,12 @@ struct ext2fs_dinode {
 	uint32_t	e2di_linux_reserved3; /* 124 */
 	uint16_t	e2di_extra_isize;
 	uint16_t	e2di_pad1;
+	uint32_t        e2di_ctime_extra; /* Extra change time */
+	uint32_t        e2di_mtime_extra; /* Extra modification time */
+	uint32_t        e2di_atime_extra; /* Extra access time */
+	uint32_t        e2di_crtime;	  /* Creation (birth)time */
+	uint32_t        e2di_crtime_extra; /* Extra creation (birth)time */
+	uint32_t        e2di_version_hi;  /* High 30 bits of inode version */
 };
 
 #endif /* !_FS_EXT2FS_EXT2_DINODE_H_ */
diff --git a/sys/fs/ext2fs/ext2_inode_cnv.c b/sys/fs/ext2fs/ext2_inode_cnv.c
index b042a5a..20361a7 100644
--- a/sys/fs/ext2fs/ext2_inode_cnv.c
+++ b/sys/fs/ext2fs/ext2_inode_cnv.c
@@ -36,6 +36,9 @@
 #include <fs/ext2fs/ext2_extern.h>
 #include <fs/ext2fs/ext2_dinode.h>
 
+#define XTIME_TO_NSEC(x)	((x & EXT3_NSEC_MASK) >> 2)
+#define NSEC_TO_XTIME(t)	((t << 2) & EXT3_NSEC_MASK)
+
 void
 ext2_print_inode( in )
 	struct inode *in;
@@ -83,6 +86,13 @@ ext2_ei2i(ei, ip)
 	ip->i_atime = ei->e2di_atime;
 	ip->i_mtime = ei->e2di_mtime;
 	ip->i_ctime = ei->e2di_ctime;
+	if (E2DI_HAS_XTIME(ip)) {
+		ip->i_atimensec = XTIME_TO_NSEC(ei->e2di_atime_extra);
+		ip->i_mtimensec = XTIME_TO_NSEC(ei->e2di_mtime_extra);
+		ip->i_ctimensec = XTIME_TO_NSEC(ei->e2di_ctime_extra);
+		ip->i_birthtime = ei->e2di_crtime;
+		ip->i_birthnsec = XTIME_TO_NSEC(ei->e2di_crtime_extra);
+	}
 	ip->i_flags = 0;
 	ip->i_flags |= (ei->e2di_flags & EXT2_APPEND) ? SF_APPEND : 0;
 	ip->i_flags |= (ei->e2di_flags & EXT2_IMMUTABLE) ? SF_IMMUTABLE : 0;
@@ -121,6 +131,13 @@ ext2_i2ei(ip, ei)
 	ei->e2di_atime = ip->i_atime;
 	ei->e2di_mtime = ip->i_mtime;
 	ei->e2di_ctime = ip->i_ctime;
+	if (E2DI_HAS_XTIME(ip)) {
+		ei->e2di_ctime_extra = NSEC_TO_XTIME(ip->i_ctimensec);
+		ei->e2di_mtime_extra = NSEC_TO_XTIME(ip->i_mtimensec);
+		ei->e2di_atime_extra = NSEC_TO_XTIME(ip->i_atimensec);
+		ei->e2di_crtime = ip->i_birthtime;
+		ei->e2di_crtime_extra = NSEC_TO_XTIME(ip->i_birthnsec);
+	}
 	ei->e2di_flags = ip->i_flags;
 	ei->e2di_flags = 0;
 	ei->e2di_flags |= (ip->i_flags & SF_APPEND) ? EXT2_APPEND: 0;
diff --git a/sys/fs/ext2fs/ext2_vfsops.c b/sys/fs/ext2fs/ext2_vfsops.c
index 8f7e8b8..48d5cb2 100644
--- a/sys/fs/ext2fs/ext2_vfsops.c
+++ b/sys/fs/ext2fs/ext2_vfsops.c
@@ -47,6 +47,7 @@
 #include <sys/bio.h>
 #include <sys/buf.h>
 #include <sys/conf.h>
+#include <sys/endian.h>
 #include <sys/fcntl.h>
 #include <sys/malloc.h>
 #include <sys/stat.h>
@@ -339,14 +340,21 @@ compute_sb_data(struct vnode *devvp, struct ext2fs *es,
 		/*
 		 * Simple sanity check for superblock inode size value.
 		 */
-		if (fs->e2fs_isize < E2FS_REV0_INODE_SIZE  ||
-		    fs->e2fs_isize > fs->e2fs_bsize ||
+		if (EXT2_INODE_SIZE(fs) < E2FS_REV0_INODE_SIZE ||
+		    EXT2_INODE_SIZE(fs) > fs->e2fs_bsize ||
 		    (fs->e2fs_isize & (fs->e2fs_isize - 1)) != 0) {
-			printf("EXT2-fs: invalid inode size %d\n",
+			printf("ext2fs: invalid inode size %d\n",
 			    fs->e2fs_isize);
 			return (EIO);
 		}
 	}
+	/* Check for extra isize in big inodes. */
+	if (EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT4F_ROCOMPAT_EXTRA_ISIZE) &&
+	    EXT2_INODE_SIZE(fs) < sizeof(struct ext2fs_dinode)) {
+		printf("ext2fs: no space for extra inode timestamps\n");
+		return (EINVAL);
+	}
+
 	fs->e2fs_ipb = fs->e2fs_bsize / EXT2_INODE_SIZE(fs);
 	fs->e2fs_itpg = fs->e2fs_ipg /fs->e2fs_ipb;
 	fs->e2fs_descpb = fs->e2fs_bsize / sizeof(struct ext2_gd);
@@ -358,8 +366,8 @@ compute_sb_data(struct vnode *devvp, struct ext2fs *es,
 	fs->e2fs_gdbcount = db_count;
 	fs->e2fs_gd = malloc(db_count * fs->e2fs_bsize,
 	    M_EXT2MNT, M_WAITOK);
-	fs->e2fs_contigdirs = malloc(fs->e2fs_gcount * sizeof(*fs->e2fs_contigdirs), 
-	    M_EXT2MNT, M_WAITOK);
+	fs->e2fs_contigdirs = malloc(fs->e2fs_gcount *
+	    sizeof(*fs->e2fs_contigdirs), M_EXT2MNT, M_WAITOK);
 
 	/*
 	 * Adjust logic_sb_block.
@@ -390,7 +398,7 @@ compute_sb_data(struct vnode *devvp, struct ext2fs *es,
 		fs->e2fs_contigdirs[i] = 0;
 	}
 	if (es->e2fs_rev == E2FS_REV0 ||
-	    (es->e2fs_features_rocompat & EXT2F_ROCOMPAT_LARGEFILE) == 0)
+	    !EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_LARGEFILE))
 		fs->e2fs_maxfilesize = 0x7fffffff;
 	else
 		fs->e2fs_maxfilesize = 0x7fffffffffffffff;
@@ -967,8 +975,6 @@ ext2_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp)
 	ip->i_block_group = ino_to_cg(fs, ino);
 	ip->i_next_alloc_block = 0;
 	ip->i_next_alloc_goal = 0;
-	ip->i_prealloc_count = 0;
-	ip->i_prealloc_block = 0;
 
 	/*
 	 * Now we want to make sure that block pointers for unused
diff --git a/sys/fs/ext2fs/ext2_vnops.c b/sys/fs/ext2fs/ext2_vnops.c
index c357a2a..136654c 100644
--- a/sys/fs/ext2fs/ext2_vnops.c
+++ b/sys/fs/ext2fs/ext2_vnops.c
@@ -360,11 +360,15 @@ ext2_getattr(ap)
 	vap->va_rdev = ip->i_rdev;
 	vap->va_size = ip->i_size;
 	vap->va_atime.tv_sec = ip->i_atime;
-	vap->va_atime.tv_nsec = ip->i_atimensec;
+	vap->va_atime.tv_nsec = E2DI_HAS_XTIME(ip) ? ip->i_atimensec : 0;
 	vap->va_mtime.tv_sec = ip->i_mtime;
-	vap->va_mtime.tv_nsec = ip->i_mtimensec;
+	vap->va_mtime.tv_nsec = E2DI_HAS_XTIME(ip) ? ip->i_mtimensec : 0;
 	vap->va_ctime.tv_sec = ip->i_ctime;
-	vap->va_ctime.tv_nsec = ip->i_ctimensec;
+	vap->va_ctime.tv_nsec = E2DI_HAS_XTIME(ip) ? ip->i_ctimensec : 0;
+	if E2DI_HAS_XTIME(ip) {
+		vap->va_birthtime.tv_sec = ip->i_birthtime;
+		vap->va_birthtime.tv_nsec = ip->i_birthnsec;
+	}
 	vap->va_flags = ip->i_flags;
 	vap->va_gen = ip->i_gen;
 	vap->va_blocksize = vp->v_mount->mnt_stat.f_iosize;
@@ -501,6 +505,8 @@ ext2_setattr(ap)
 			ip->i_mtime = vap->va_mtime.tv_sec;
 			ip->i_mtimensec = vap->va_mtime.tv_nsec;
 		}
+		ip->i_birthtime = vap->va_birthtime.tv_sec;
+		ip->i_birthnsec = vap->va_birthtime.tv_nsec;
 		error = ext2_update(vp, 0);
 		if (error)
 			return (error);
diff --git a/sys/fs/ext2fs/ext2fs.h b/sys/fs/ext2fs/ext2fs.h
index 14027ab..83e2a68 100755
--- a/sys/fs/ext2fs/ext2fs.h
+++ b/sys/fs/ext2fs/ext2fs.h
@@ -129,7 +129,7 @@ struct ext2fs {
 	uint32_t  e4fs_rbcount_hi;     /* reserved blocks count */
 	uint32_t  e4fs_fbcount_hi;     /* free blocks count */
 	uint16_t  e4fs_min_extra_isize;/* all inodes have at least some bytes */
-	uint16_t  e4fs_want_extra_isize; /* new inodes should reserve some bytes */
+	uint16_t  e4fs_want_extra_isize; /* inodes must reserve some bytes */
 	uint32_t  e4fs_flags;	  /* miscellaneous flags */
 	uint16_t  e4fs_raid_stride;    /* RAID stride */
 	uint16_t  e4fs_mmpintv;	/* number of seconds to wait in MMP checking */
@@ -214,6 +214,7 @@ struct m_ext2fs {
 #define EXT2F_ROCOMPAT_SPARSESUPER	0x0001
 #define EXT2F_ROCOMPAT_LARGEFILE	0x0002
 #define EXT2F_ROCOMPAT_BTREE_DIR	0x0004
+#define EXT4F_ROCOMPAT_EXTRA_ISIZE	0x0040
 
 #define EXT2F_INCOMPAT_COMP		0x0001
 #define EXT2F_INCOMPAT_FTYPE		0x0002
@@ -227,8 +228,9 @@ struct m_ext2fs {
  * - EXT2F_INCOMPAT_FTYPE
  */
 #define EXT2F_COMPAT_SUPP		0x0000
-#define EXT2F_ROCOMPAT_SUPP		(EXT2F_ROCOMPAT_SPARSESUPER \
-					 | EXT2F_ROCOMPAT_LARGEFILE)
+#define EXT2F_ROCOMPAT_SUPP		(EXT2F_ROCOMPAT_SPARSESUPER | \
+					 EXT2F_ROCOMPAT_LARGEFILE | \
+					 EXT4F_ROCOMPAT_EXTRA_ISIZE)
 #define EXT2F_INCOMPAT_SUPP		EXT2F_INCOMPAT_FTYPE
 
 /* Assume that user mode programs are passing in an ext2fs superblock, not
diff --git a/sys/fs/ext2fs/inode.h b/sys/fs/ext2fs/inode.h
index 659b950..100a076 100644
--- a/sys/fs/ext2fs/inode.h
+++ b/sys/fs/ext2fs/inode.h
@@ -77,8 +77,6 @@ struct inode {
 	uint32_t i_block_group;
 	uint32_t i_next_alloc_block;
 	uint32_t i_next_alloc_goal;
-	uint32_t i_prealloc_block;
-	uint32_t i_prealloc_count;
 
 	/* Fields from struct dinode in UFS. */
 	uint16_t	i_mode;		/* IFMT, permissions; see below. */