File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/fs/ufs/ialloc.c b/fs/ufs/ialloc.c
new file mode 100644
index 0000000..fd0203c
--- /dev/null
+++ b/fs/ufs/ialloc.c
@@ -0,0 +1,353 @@
+/*
+ *  linux/fs/ufs/ialloc.c
+ *
+ * Copyright (c) 1998
+ * Daniel Pirkl <daniel.pirkl@email.cz>
+ * Charles University, Faculty of Mathematics and Physics
+ *
+ *  from
+ *
+ *  linux/fs/ext2/ialloc.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ *  BSD ufs-inspired inode and directory allocation by 
+ *  Stephen Tweedie (sct@dcs.ed.ac.uk), 1993
+ *  Big-endian to little-endian byte-swapping/bitmaps by
+ *        David S. Miller (davem@caip.rutgers.edu), 1995
+ *
+ * UFS2 write support added by
+ * Evgeniy Dushistov <dushistov@mail.ru>, 2007
+ */
+
+#include <linux/fs.h>
+#include <linux/time.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/buffer_head.h>
+#include <linux/sched.h>
+#include <linux/bitops.h>
+#include <asm/byteorder.h>
+
+#include "ufs_fs.h"
+#include "ufs.h"
+#include "swab.h"
+#include "util.h"
+
+/*
+ * NOTE! When we get the inode, we're the only people
+ * that have access to it, and as such there are no
+ * race conditions we have to worry about. The inode
+ * is not on the hash-lists, and it cannot be reached
+ * through the filesystem because the directory entry
+ * has been deleted earlier.
+ *
+ * HOWEVER: we must make sure that we get no aliases,
+ * which means that we have to call "clear_inode()"
+ * _before_ we mark the inode not in use in the inode
+ * bitmaps. Otherwise a newly created file might use
+ * the same inode number (not actually the same pointer
+ * though), and then we'd have two inodes sharing the
+ * same inode number and space on the harddisk.
+ */
+void ufs_free_inode (struct inode * inode)
+{
+	struct super_block * sb;
+	struct ufs_sb_private_info * uspi;
+	struct ufs_cg_private_info * ucpi;
+	struct ufs_cylinder_group * ucg;
+	int is_directory;
+	unsigned ino, cg, bit;
+	
+	UFSD("ENTER, ino %lu\n", inode->i_ino);
+
+	sb = inode->i_sb;
+	uspi = UFS_SB(sb)->s_uspi;
+	
+	ino = inode->i_ino;
+
+	mutex_lock(&UFS_SB(sb)->s_lock);
+
+	if (!((ino > 1) && (ino < (uspi->s_ncg * uspi->s_ipg )))) {
+		ufs_warning(sb, "ufs_free_inode", "reserved inode or nonexistent inode %u\n", ino);
+		mutex_unlock(&UFS_SB(sb)->s_lock);
+		return;
+	}
+	
+	cg = ufs_inotocg (ino);
+	bit = ufs_inotocgoff (ino);
+	ucpi = ufs_load_cylinder (sb, cg);
+	if (!ucpi) {
+		mutex_unlock(&UFS_SB(sb)->s_lock);
+		return;
+	}
+	ucg = ubh_get_ucg(UCPI_UBH(ucpi));
+	if (!ufs_cg_chkmagic(sb, ucg))
+		ufs_panic (sb, "ufs_free_fragments", "internal error, bad cg magic number");
+
+	ucg->cg_time = cpu_to_fs32(sb, get_seconds());
+
+	is_directory = S_ISDIR(inode->i_mode);
+
+	if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit))
+		ufs_error(sb, "ufs_free_inode", "bit already cleared for inode %u", ino);
+	else {
+		ubh_clrbit (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit);
+		if (ino < ucpi->c_irotor)
+			ucpi->c_irotor = ino;
+		fs32_add(sb, &ucg->cg_cs.cs_nifree, 1);
+		uspi->cs_total.cs_nifree++;
+		fs32_add(sb, &UFS_SB(sb)->fs_cs(cg).cs_nifree, 1);
+
+		if (is_directory) {
+			fs32_sub(sb, &ucg->cg_cs.cs_ndir, 1);
+			uspi->cs_total.cs_ndir--;
+			fs32_sub(sb, &UFS_SB(sb)->fs_cs(cg).cs_ndir, 1);
+		}
+	}
+
+	ubh_mark_buffer_dirty (USPI_UBH(uspi));
+	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
+	if (sb->s_flags & MS_SYNCHRONOUS)
+		ubh_sync_block(UCPI_UBH(ucpi));
+	
+	ufs_mark_sb_dirty(sb);
+	mutex_unlock(&UFS_SB(sb)->s_lock);
+	UFSD("EXIT\n");
+}
+
+/*
+ * Nullify new chunk of inodes,
+ * BSD people also set ui_gen field of inode
+ * during nullification, but we not care about
+ * that because of linux ufs do not support NFS
+ */
+static void ufs2_init_inodes_chunk(struct super_block *sb,
+				   struct ufs_cg_private_info *ucpi,
+				   struct ufs_cylinder_group *ucg)
+{
+	struct buffer_head *bh;
+	struct ufs_sb_private_info *uspi = UFS_SB(sb)->s_uspi;
+	sector_t beg = uspi->s_sbbase +
+		ufs_inotofsba(ucpi->c_cgx * uspi->s_ipg +
+			      fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_initediblk));
+	sector_t end = beg + uspi->s_fpb;
+
+	UFSD("ENTER cgno %d\n", ucpi->c_cgx);
+
+	for (; beg < end; ++beg) {
+		bh = sb_getblk(sb, beg);
+		lock_buffer(bh);
+		memset(bh->b_data, 0, sb->s_blocksize);
+		set_buffer_uptodate(bh);
+		mark_buffer_dirty(bh);
+		unlock_buffer(bh);
+		if (sb->s_flags & MS_SYNCHRONOUS)
+			sync_dirty_buffer(bh);
+		brelse(bh);
+	}
+
+	fs32_add(sb, &ucg->cg_u.cg_u2.cg_initediblk, uspi->s_inopb);
+	ubh_mark_buffer_dirty(UCPI_UBH(ucpi));
+	if (sb->s_flags & MS_SYNCHRONOUS)
+		ubh_sync_block(UCPI_UBH(ucpi));
+
+	UFSD("EXIT\n");
+}
+
+/*
+ * There are two policies for allocating an inode.  If the new inode is
+ * a directory, then a forward search is made for a block group with both
+ * free space and a low directory-to-inode ratio; if that fails, then of
+ * the groups with above-average free space, that group with the fewest
+ * directories already is chosen.
+ *
+ * For other inodes, search forward from the parent directory's block
+ * group to find a free inode.
+ */
+struct inode *ufs_new_inode(struct inode *dir, umode_t mode)
+{
+	struct super_block * sb;
+	struct ufs_sb_info * sbi;
+	struct ufs_sb_private_info * uspi;
+	struct ufs_cg_private_info * ucpi;
+	struct ufs_cylinder_group * ucg;
+	struct inode * inode;
+	unsigned cg, bit, i, j, start;
+	struct ufs_inode_info *ufsi;
+	int err = -ENOSPC;
+
+	UFSD("ENTER\n");
+	
+	/* Cannot create files in a deleted directory */
+	if (!dir || !dir->i_nlink)
+		return ERR_PTR(-EPERM);
+	sb = dir->i_sb;
+	inode = new_inode(sb);
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+	ufsi = UFS_I(inode);
+	sbi = UFS_SB(sb);
+	uspi = sbi->s_uspi;
+
+	mutex_lock(&sbi->s_lock);
+
+	/*
+	 * Try to place the inode in its parent directory
+	 */
+	i = ufs_inotocg(dir->i_ino);
+	if (sbi->fs_cs(i).cs_nifree) {
+		cg = i;
+		goto cg_found;
+	}
+
+	/*
+	 * Use a quadratic hash to find a group with a free inode
+	 */
+	for ( j = 1; j < uspi->s_ncg; j <<= 1 ) {
+		i += j;
+		if (i >= uspi->s_ncg)
+			i -= uspi->s_ncg;
+		if (sbi->fs_cs(i).cs_nifree) {
+			cg = i;
+			goto cg_found;
+		}
+	}
+
+	/*
+	 * That failed: try linear search for a free inode
+	 */
+	i = ufs_inotocg(dir->i_ino) + 1;
+	for (j = 2; j < uspi->s_ncg; j++) {
+		i++;
+		if (i >= uspi->s_ncg)
+			i = 0;
+		if (sbi->fs_cs(i).cs_nifree) {
+			cg = i;
+			goto cg_found;
+		}
+	}
+
+	goto failed;
+
+cg_found:
+	ucpi = ufs_load_cylinder (sb, cg);
+	if (!ucpi) {
+		err = -EIO;
+		goto failed;
+	}
+	ucg = ubh_get_ucg(UCPI_UBH(ucpi));
+	if (!ufs_cg_chkmagic(sb, ucg)) 
+		ufs_panic (sb, "ufs_new_inode", "internal error, bad cg magic number");
+
+	start = ucpi->c_irotor;
+	bit = ubh_find_next_zero_bit (UCPI_UBH(ucpi), ucpi->c_iusedoff, uspi->s_ipg, start);
+	if (!(bit < uspi->s_ipg)) {
+		bit = ubh_find_first_zero_bit (UCPI_UBH(ucpi), ucpi->c_iusedoff, start);
+		if (!(bit < start)) {
+			ufs_error (sb, "ufs_new_inode",
+			    "cylinder group %u corrupted - error in inode bitmap\n", cg);
+			err = -EIO;
+			goto failed;
+		}
+	}
+	UFSD("start = %u, bit = %u, ipg = %u\n", start, bit, uspi->s_ipg);
+	if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit))
+		ubh_setbit (UCPI_UBH(ucpi), ucpi->c_iusedoff, bit);
+	else {
+		ufs_panic (sb, "ufs_new_inode", "internal error");
+		err = -EIO;
+		goto failed;
+	}
+
+	if (uspi->fs_magic == UFS2_MAGIC) {
+		u32 initediblk = fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_initediblk);
+
+		if (bit + uspi->s_inopb > initediblk &&
+		    initediblk < fs32_to_cpu(sb, ucg->cg_u.cg_u2.cg_niblk))
+			ufs2_init_inodes_chunk(sb, ucpi, ucg);
+	}
+
+	fs32_sub(sb, &ucg->cg_cs.cs_nifree, 1);
+	uspi->cs_total.cs_nifree--;
+	fs32_sub(sb, &sbi->fs_cs(cg).cs_nifree, 1);
+	
+	if (S_ISDIR(mode)) {
+		fs32_add(sb, &ucg->cg_cs.cs_ndir, 1);
+		uspi->cs_total.cs_ndir++;
+		fs32_add(sb, &sbi->fs_cs(cg).cs_ndir, 1);
+	}
+	ubh_mark_buffer_dirty (USPI_UBH(uspi));
+	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
+	if (sb->s_flags & MS_SYNCHRONOUS)
+		ubh_sync_block(UCPI_UBH(ucpi));
+	ufs_mark_sb_dirty(sb);
+
+	inode->i_ino = cg * uspi->s_ipg + bit;
+	inode_init_owner(inode, dir, mode);
+	inode->i_blocks = 0;
+	inode->i_generation = 0;
+	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
+	ufsi->i_flags = UFS_I(dir)->i_flags;
+	ufsi->i_lastfrag = 0;
+	ufsi->i_shadow = 0;
+	ufsi->i_osync = 0;
+	ufsi->i_oeftflag = 0;
+	ufsi->i_dir_start_lookup = 0;
+	memset(&ufsi->i_u1, 0, sizeof(ufsi->i_u1));
+	if (insert_inode_locked(inode) < 0) {
+		err = -EIO;
+		goto failed;
+	}
+	mark_inode_dirty(inode);
+
+	if (uspi->fs_magic == UFS2_MAGIC) {
+		struct buffer_head *bh;
+		struct ufs2_inode *ufs2_inode;
+
+		/*
+		 * setup birth date, we do it here because of there is no sense
+		 * to hold it in struct ufs_inode_info, and lose 64 bit
+		 */
+		bh = sb_bread(sb, uspi->s_sbbase + ufs_inotofsba(inode->i_ino));
+		if (!bh) {
+			ufs_warning(sb, "ufs_read_inode",
+				    "unable to read inode %lu\n",
+				    inode->i_ino);
+			err = -EIO;
+			goto fail_remove_inode;
+		}
+		lock_buffer(bh);
+		ufs2_inode = (struct ufs2_inode *)bh->b_data;
+		ufs2_inode += ufs_inotofsbo(inode->i_ino);
+		ufs2_inode->ui_birthtime = cpu_to_fs64(sb, CURRENT_TIME.tv_sec);
+		ufs2_inode->ui_birthnsec = cpu_to_fs32(sb, CURRENT_TIME.tv_nsec);
+		mark_buffer_dirty(bh);
+		unlock_buffer(bh);
+		if (sb->s_flags & MS_SYNCHRONOUS)
+			sync_dirty_buffer(bh);
+		brelse(bh);
+	}
+	mutex_unlock(&sbi->s_lock);
+
+	UFSD("allocating inode %lu\n", inode->i_ino);
+	UFSD("EXIT\n");
+	return inode;
+
+fail_remove_inode:
+	mutex_unlock(&sbi->s_lock);
+	clear_nlink(inode);
+	unlock_new_inode(inode);
+	iput(inode);
+	UFSD("EXIT (FAILED): err %d\n", err);
+	return ERR_PTR(err);
+failed:
+	mutex_unlock(&sbi->s_lock);
+	make_bad_inode(inode);
+	iput (inode);
+	UFSD("EXIT (FAILED): err %d\n", err);
+	return ERR_PTR(err);
+}