xfs: introduce xfs_inode_buf.c for inode buffer operations
The only thing remaining in xfs_inode.[ch] are the operations that
read, write or verify physical inodes in their underlying buffers.
Move all this code to xfs_inode_buf.[ch] and so we can stop sharing
xfs_inode.[ch] with userspace.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
diff --git a/fs/xfs/xfs_inode_buf.c b/fs/xfs/xfs_inode_buf.c
new file mode 100644
index 0000000..38fe509
--- /dev/null
+++ b/fs/xfs/xfs_inode_buf.c
@@ -0,0 +1,453 @@
+/*
+ * Copyright (c) 2000-2006 Silicon Graphics, Inc.
+ * All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_format.h"
+#include "xfs_log.h"
+#include "xfs_trans.h"
+#include "xfs_sb.h"
+#include "xfs_ag.h"
+#include "xfs_mount.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_ialloc_btree.h"
+#include "xfs_dinode.h"
+#include "xfs_inode.h"
+#include "xfs_error.h"
+#include "xfs_cksum.h"
+#include "xfs_icache.h"
+#include "xfs_ialloc.h"
+
+/*
+ * Check that none of the inode's in the buffer have a next
+ * unlinked field of 0.
+ */
+#if defined(DEBUG)
+void
+xfs_inobp_check(
+ xfs_mount_t *mp,
+ xfs_buf_t *bp)
+{
+ int i;
+ int j;
+ xfs_dinode_t *dip;
+
+ j = mp->m_inode_cluster_size >> mp->m_sb.sb_inodelog;
+
+ for (i = 0; i < j; i++) {
+ dip = (xfs_dinode_t *)xfs_buf_offset(bp,
+ i * mp->m_sb.sb_inodesize);
+ if (!dip->di_next_unlinked) {
+ xfs_alert(mp,
+ "Detected bogus zero next_unlinked field in incore inode buffer 0x%p.",
+ bp);
+ ASSERT(dip->di_next_unlinked);
+ }
+ }
+}
+#endif
+
+static void
+xfs_inode_buf_verify(
+ struct xfs_buf *bp)
+{
+ struct xfs_mount *mp = bp->b_target->bt_mount;
+ int i;
+ int ni;
+
+ /*
+ * Validate the magic number and version of every inode in the buffer
+ */
+ ni = XFS_BB_TO_FSB(mp, bp->b_length) * mp->m_sb.sb_inopblock;
+ for (i = 0; i < ni; i++) {
+ int di_ok;
+ xfs_dinode_t *dip;
+
+ dip = (struct xfs_dinode *)xfs_buf_offset(bp,
+ (i << mp->m_sb.sb_inodelog));
+ di_ok = dip->di_magic == cpu_to_be16(XFS_DINODE_MAGIC) &&
+ XFS_DINODE_GOOD_VERSION(dip->di_version);
+ if (unlikely(XFS_TEST_ERROR(!di_ok, mp,
+ XFS_ERRTAG_ITOBP_INOTOBP,
+ XFS_RANDOM_ITOBP_INOTOBP))) {
+ xfs_buf_ioerror(bp, EFSCORRUPTED);
+ XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_HIGH,
+ mp, dip);
+#ifdef DEBUG
+ xfs_emerg(mp,
+ "bad inode magic/vsn daddr %lld #%d (magic=%x)",
+ (unsigned long long)bp->b_bn, i,
+ be16_to_cpu(dip->di_magic));
+ ASSERT(0);
+#endif
+ }
+ }
+ xfs_inobp_check(mp, bp);
+}
+
+
+static void
+xfs_inode_buf_read_verify(
+ struct xfs_buf *bp)
+{
+ xfs_inode_buf_verify(bp);
+}
+
+static void
+xfs_inode_buf_write_verify(
+ struct xfs_buf *bp)
+{
+ xfs_inode_buf_verify(bp);
+}
+
+const struct xfs_buf_ops xfs_inode_buf_ops = {
+ .verify_read = xfs_inode_buf_read_verify,
+ .verify_write = xfs_inode_buf_write_verify,
+};
+
+
+/*
+ * This routine is called to map an inode to the buffer containing the on-disk
+ * version of the inode. It returns a pointer to the buffer containing the
+ * on-disk inode in the bpp parameter, and in the dipp parameter it returns a
+ * pointer to the on-disk inode within that buffer.
+ *
+ * If a non-zero error is returned, then the contents of bpp and dipp are
+ * undefined.
+ */
+int
+xfs_imap_to_bp(
+ struct xfs_mount *mp,
+ struct xfs_trans *tp,
+ struct xfs_imap *imap,
+ struct xfs_dinode **dipp,
+ struct xfs_buf **bpp,
+ uint buf_flags,
+ uint iget_flags)
+{
+ struct xfs_buf *bp;
+ int error;
+
+ buf_flags |= XBF_UNMAPPED;
+ error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, imap->im_blkno,
+ (int)imap->im_len, buf_flags, &bp,
+ &xfs_inode_buf_ops);
+ if (error) {
+ if (error == EAGAIN) {
+ ASSERT(buf_flags & XBF_TRYLOCK);
+ return error;
+ }
+
+ if (error == EFSCORRUPTED &&
+ (iget_flags & XFS_IGET_UNTRUSTED))
+ return XFS_ERROR(EINVAL);
+
+ xfs_warn(mp, "%s: xfs_trans_read_buf() returned error %d.",
+ __func__, error);
+ return error;
+ }
+
+ *bpp = bp;
+ *dipp = (struct xfs_dinode *)xfs_buf_offset(bp, imap->im_boffset);
+ return 0;
+}
+
+STATIC void
+xfs_dinode_from_disk(
+ xfs_icdinode_t *to,
+ xfs_dinode_t *from)
+{
+ to->di_magic = be16_to_cpu(from->di_magic);
+ to->di_mode = be16_to_cpu(from->di_mode);
+ to->di_version = from ->di_version;
+ to->di_format = from->di_format;
+ to->di_onlink = be16_to_cpu(from->di_onlink);
+ to->di_uid = be32_to_cpu(from->di_uid);
+ to->di_gid = be32_to_cpu(from->di_gid);
+ to->di_nlink = be32_to_cpu(from->di_nlink);
+ to->di_projid_lo = be16_to_cpu(from->di_projid_lo);
+ to->di_projid_hi = be16_to_cpu(from->di_projid_hi);
+ memcpy(to->di_pad, from->di_pad, sizeof(to->di_pad));
+ to->di_flushiter = be16_to_cpu(from->di_flushiter);
+ to->di_atime.t_sec = be32_to_cpu(from->di_atime.t_sec);
+ to->di_atime.t_nsec = be32_to_cpu(from->di_atime.t_nsec);
+ to->di_mtime.t_sec = be32_to_cpu(from->di_mtime.t_sec);
+ to->di_mtime.t_nsec = be32_to_cpu(from->di_mtime.t_nsec);
+ to->di_ctime.t_sec = be32_to_cpu(from->di_ctime.t_sec);
+ to->di_ctime.t_nsec = be32_to_cpu(from->di_ctime.t_nsec);
+ to->di_size = be64_to_cpu(from->di_size);
+ to->di_nblocks = be64_to_cpu(from->di_nblocks);
+ to->di_extsize = be32_to_cpu(from->di_extsize);
+ to->di_nextents = be32_to_cpu(from->di_nextents);
+ to->di_anextents = be16_to_cpu(from->di_anextents);
+ to->di_forkoff = from->di_forkoff;
+ to->di_aformat = from->di_aformat;
+ to->di_dmevmask = be32_to_cpu(from->di_dmevmask);
+ to->di_dmstate = be16_to_cpu(from->di_dmstate);
+ to->di_flags = be16_to_cpu(from->di_flags);
+ to->di_gen = be32_to_cpu(from->di_gen);
+
+ if (to->di_version == 3) {
+ to->di_changecount = be64_to_cpu(from->di_changecount);
+ to->di_crtime.t_sec = be32_to_cpu(from->di_crtime.t_sec);
+ to->di_crtime.t_nsec = be32_to_cpu(from->di_crtime.t_nsec);
+ to->di_flags2 = be64_to_cpu(from->di_flags2);
+ to->di_ino = be64_to_cpu(from->di_ino);
+ to->di_lsn = be64_to_cpu(from->di_lsn);
+ memcpy(to->di_pad2, from->di_pad2, sizeof(to->di_pad2));
+ uuid_copy(&to->di_uuid, &from->di_uuid);
+ }
+}
+
+void
+xfs_dinode_to_disk(
+ xfs_dinode_t *to,
+ xfs_icdinode_t *from)
+{
+ to->di_magic = cpu_to_be16(from->di_magic);
+ to->di_mode = cpu_to_be16(from->di_mode);
+ to->di_version = from ->di_version;
+ to->di_format = from->di_format;
+ to->di_onlink = cpu_to_be16(from->di_onlink);
+ to->di_uid = cpu_to_be32(from->di_uid);
+ to->di_gid = cpu_to_be32(from->di_gid);
+ to->di_nlink = cpu_to_be32(from->di_nlink);
+ to->di_projid_lo = cpu_to_be16(from->di_projid_lo);
+ to->di_projid_hi = cpu_to_be16(from->di_projid_hi);
+ memcpy(to->di_pad, from->di_pad, sizeof(to->di_pad));
+ to->di_atime.t_sec = cpu_to_be32(from->di_atime.t_sec);
+ to->di_atime.t_nsec = cpu_to_be32(from->di_atime.t_nsec);
+ to->di_mtime.t_sec = cpu_to_be32(from->di_mtime.t_sec);
+ to->di_mtime.t_nsec = cpu_to_be32(from->di_mtime.t_nsec);
+ to->di_ctime.t_sec = cpu_to_be32(from->di_ctime.t_sec);
+ to->di_ctime.t_nsec = cpu_to_be32(from->di_ctime.t_nsec);
+ to->di_size = cpu_to_be64(from->di_size);
+ to->di_nblocks = cpu_to_be64(from->di_nblocks);
+ to->di_extsize = cpu_to_be32(from->di_extsize);
+ to->di_nextents = cpu_to_be32(from->di_nextents);
+ to->di_anextents = cpu_to_be16(from->di_anextents);
+ to->di_forkoff = from->di_forkoff;
+ to->di_aformat = from->di_aformat;
+ to->di_dmevmask = cpu_to_be32(from->di_dmevmask);
+ to->di_dmstate = cpu_to_be16(from->di_dmstate);
+ to->di_flags = cpu_to_be16(from->di_flags);
+ to->di_gen = cpu_to_be32(from->di_gen);
+
+ if (from->di_version == 3) {
+ to->di_changecount = cpu_to_be64(from->di_changecount);
+ to->di_crtime.t_sec = cpu_to_be32(from->di_crtime.t_sec);
+ to->di_crtime.t_nsec = cpu_to_be32(from->di_crtime.t_nsec);
+ to->di_flags2 = cpu_to_be64(from->di_flags2);
+ to->di_ino = cpu_to_be64(from->di_ino);
+ to->di_lsn = cpu_to_be64(from->di_lsn);
+ memcpy(to->di_pad2, from->di_pad2, sizeof(to->di_pad2));
+ uuid_copy(&to->di_uuid, &from->di_uuid);
+ to->di_flushiter = 0;
+ } else {
+ to->di_flushiter = cpu_to_be16(from->di_flushiter);
+ }
+}
+
+static bool
+xfs_dinode_verify(
+ struct xfs_mount *mp,
+ struct xfs_inode *ip,
+ struct xfs_dinode *dip)
+{
+ if (dip->di_magic != cpu_to_be16(XFS_DINODE_MAGIC))
+ return false;
+
+ /* only version 3 or greater inodes are extensively verified here */
+ if (dip->di_version < 3)
+ return true;
+
+ if (!xfs_sb_version_hascrc(&mp->m_sb))
+ return false;
+ if (!xfs_verify_cksum((char *)dip, mp->m_sb.sb_inodesize,
+ offsetof(struct xfs_dinode, di_crc)))
+ return false;
+ if (be64_to_cpu(dip->di_ino) != ip->i_ino)
+ return false;
+ if (!uuid_equal(&dip->di_uuid, &mp->m_sb.sb_uuid))
+ return false;
+ return true;
+}
+
+void
+xfs_dinode_calc_crc(
+ struct xfs_mount *mp,
+ struct xfs_dinode *dip)
+{
+ __uint32_t crc;
+
+ if (dip->di_version < 3)
+ return;
+
+ ASSERT(xfs_sb_version_hascrc(&mp->m_sb));
+ crc = xfs_start_cksum((char *)dip, mp->m_sb.sb_inodesize,
+ offsetof(struct xfs_dinode, di_crc));
+ dip->di_crc = xfs_end_cksum(crc);
+}
+
+/*
+ * Read the disk inode attributes into the in-core inode structure.
+ *
+ * For version 5 superblocks, if we are initialising a new inode and we are not
+ * utilising the XFS_MOUNT_IKEEP inode cluster mode, we can simple build the new
+ * inode core with a random generation number. If we are keeping inodes around,
+ * we need to read the inode cluster to get the existing generation number off
+ * disk. Further, if we are using version 4 superblocks (i.e. v1/v2 inode
+ * format) then log recovery is dependent on the di_flushiter field being
+ * initialised from the current on-disk value and hence we must also read the
+ * inode off disk.
+ */
+int
+xfs_iread(
+ xfs_mount_t *mp,
+ xfs_trans_t *tp,
+ xfs_inode_t *ip,
+ uint iget_flags)
+{
+ xfs_buf_t *bp;
+ xfs_dinode_t *dip;
+ int error;
+
+ /*
+ * Fill in the location information in the in-core inode.
+ */
+ error = xfs_imap(mp, tp, ip->i_ino, &ip->i_imap, iget_flags);
+ if (error)
+ return error;
+
+ /* shortcut IO on inode allocation if possible */
+ if ((iget_flags & XFS_IGET_CREATE) &&
+ xfs_sb_version_hascrc(&mp->m_sb) &&
+ !(mp->m_flags & XFS_MOUNT_IKEEP)) {
+ /* initialise the on-disk inode core */
+ memset(&ip->i_d, 0, sizeof(ip->i_d));
+ ip->i_d.di_magic = XFS_DINODE_MAGIC;
+ ip->i_d.di_gen = prandom_u32();
+ if (xfs_sb_version_hascrc(&mp->m_sb)) {
+ ip->i_d.di_version = 3;
+ ip->i_d.di_ino = ip->i_ino;
+ uuid_copy(&ip->i_d.di_uuid, &mp->m_sb.sb_uuid);
+ } else
+ ip->i_d.di_version = 2;
+ return 0;
+ }
+
+ /*
+ * Get pointers to the on-disk inode and the buffer containing it.
+ */
+ error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &dip, &bp, 0, iget_flags);
+ if (error)
+ return error;
+
+ /* even unallocated inodes are verified */
+ if (!xfs_dinode_verify(mp, ip, dip)) {
+ xfs_alert(mp, "%s: validation failed for inode %lld failed",
+ __func__, ip->i_ino);
+
+ XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, dip);
+ error = XFS_ERROR(EFSCORRUPTED);
+ goto out_brelse;
+ }
+
+ /*
+ * If the on-disk inode is already linked to a directory
+ * entry, copy all of the inode into the in-core inode.
+ * xfs_iformat_fork() handles copying in the inode format
+ * specific information.
+ * Otherwise, just get the truly permanent information.
+ */
+ if (dip->di_mode) {
+ xfs_dinode_from_disk(&ip->i_d, dip);
+ error = xfs_iformat_fork(ip, dip);
+ if (error) {
+#ifdef DEBUG
+ xfs_alert(mp, "%s: xfs_iformat() returned error %d",
+ __func__, error);
+#endif /* DEBUG */
+ goto out_brelse;
+ }
+ } else {
+ /*
+ * Partial initialisation of the in-core inode. Just the bits
+ * that xfs_ialloc won't overwrite or relies on being correct.
+ */
+ ip->i_d.di_magic = be16_to_cpu(dip->di_magic);
+ ip->i_d.di_version = dip->di_version;
+ ip->i_d.di_gen = be32_to_cpu(dip->di_gen);
+ ip->i_d.di_flushiter = be16_to_cpu(dip->di_flushiter);
+
+ if (dip->di_version == 3) {
+ ip->i_d.di_ino = be64_to_cpu(dip->di_ino);
+ uuid_copy(&ip->i_d.di_uuid, &dip->di_uuid);
+ }
+
+ /*
+ * Make sure to pull in the mode here as well in
+ * case the inode is released without being used.
+ * This ensures that xfs_inactive() will see that
+ * the inode is already free and not try to mess
+ * with the uninitialized part of it.
+ */
+ ip->i_d.di_mode = 0;
+ }
+
+ /*
+ * The inode format changed when we moved the link count and
+ * made it 32 bits long. If this is an old format inode,
+ * convert it in memory to look like a new one. If it gets
+ * flushed to disk we will convert back before flushing or
+ * logging it. We zero out the new projid field and the old link
+ * count field. We'll handle clearing the pad field (the remains
+ * of the old uuid field) when we actually convert the inode to
+ * the new format. We don't change the version number so that we
+ * can distinguish this from a real new format inode.
+ */
+ if (ip->i_d.di_version == 1) {
+ ip->i_d.di_nlink = ip->i_d.di_onlink;
+ ip->i_d.di_onlink = 0;
+ xfs_set_projid(ip, 0);
+ }
+
+ ip->i_delayed_blks = 0;
+
+ /*
+ * Mark the buffer containing the inode as something to keep
+ * around for a while. This helps to keep recently accessed
+ * meta-data in-core longer.
+ */
+ xfs_buf_set_ref(bp, XFS_INO_REF);
+
+ /*
+ * Use xfs_trans_brelse() to release the buffer containing the on-disk
+ * inode, because it was acquired with xfs_trans_read_buf() in
+ * xfs_imap_to_bp() above. If tp is NULL, this is just a normal
+ * brelse(). If we're within a transaction, then xfs_trans_brelse()
+ * will only release the buffer if it is not dirty within the
+ * transaction. It will be OK to release the buffer in this case,
+ * because inodes on disk are never destroyed and we will be locking the
+ * new in-core inode before putting it in the cache where other
+ * processes can find it. Thus we don't have to worry about the inode
+ * being changed just because we released the buffer.
+ */
+ out_brelse:
+ xfs_trans_brelse(tp, bp);
+ return error;
+}