patch-2.1.112 linux/fs/ufs/ialloc.c

• Lines: 342
• Date: Sun Jul 26 01:20:22 1998
• Orig file: v2.1.111/linux/fs/ufs/ialloc.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.111/linux/fs/ufs/ialloc.c linux/fs/ufs/ialloc.c
@@ -0,0 +1,341 @@
+/*
+ *  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
+ */
+
+#include <linux/fs.h>
+#include <linux/ufs_fs.h>
+#include <linux/sched.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/locks.h>
+#include <linux/quotaops.h>
+#include <asm/bitops.h>
+#include <asm/byteorder.h>
+
+#include "swab.h"
+#include "util.h"
+
+#undef UFS_IALLOC_DEBUG
+#undef UFS_IALLOC_DEBUG_MORE
+
+#ifdef UFS_IALLOC_DEBUG
+#define UFSD(x) printk("(%s, %d), %s: ", __FILE__, __LINE__, __FUNCTION__); printk x;
+#else
+#define UFSD(x)
+#endif
+
+#ifdef UFS_IALLOC_DEBUG_MORE
+#define UFSDM \
+ufs_print_cylinder_stuff (ucg, swab); \
+printk("inode: total %u, fs %u, cg %u\n", SWAB32(usb1->fs_cstotal.cs_nifree), SWAB32(sb->fs_cs(ucpi->c_cgx).cs_nifree), SWAB32(ucg->cg_cs.cs_nifree)); \
+printk("block: total %u, fs %u, cg %u\n", SWAB32(usb1->fs_cstotal.cs_nbfree), SWAB32(sb->fs_cs(ucpi->c_cgx).cs_nbfree), SWAB32(ucg->cg_cs.cs_nbfree)); \
+printk("fragment: total %u, fs %u, cg %u\n", SWAB32(usb1->fs_cstotal.cs_nffree), SWAB32(sb->fs_cs(ucpi->c_cgx).cs_nffree), SWAB32(ucg->cg_cs.cs_nffree)); \
+printk("ndir: total %u, fs %u, cg %u\n", SWAB32(usb1->fs_cstotal.cs_ndir), SWAB32(sb->fs_cs(ucpi->c_cgx).cs_ndir), SWAB32(ucg->cg_cs.cs_ndir));
+#else
+#define UFSDM
+#endif
+
+
+/*
+ * 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_super_block_first * usb1;
+	struct ufs_cg_private_info * ucpi;
+	struct ufs_cylinder_group * ucg;
+	int is_directory;
+	unsigned ino, cg, bit;
+	unsigned swab;
+	
+	UFSD(("ENTER, ino %lu\n", inode->i_ino))
+
+	if (!inode)
+		return;
+	sb = inode->i_sb;
+	swab = sb->u.ufs_sb.s_swab;
+	uspi = sb->u.ufs_sb.s_uspi;
+	usb1 = ubh_get_usb_first(USPI_UBH);
+	
+	if (inode->i_count > 1) {
+		ufs_warning(sb, "ufs_free_inode", "inode has count=%d\n", inode->i_count);
+		return;
+	}
+	if (inode->i_nlink) {
+		ufs_warning(sb, "ufs_free_inode", "inode has nlink=%d\n", inode->i_nlink);
+		return;
+	}
+
+	ino = inode->i_ino;
+
+	lock_super (sb);
+
+	if (!((ino > 1) && (ino < (uspi->s_ncg * uspi->s_ipg )))) {
+		ufs_warning(sb, "ufs_free_inode", "reserved inode or nonexistent inode %u\n", ino);
+		unlock_super (sb);
+		return;
+	}
+	
+	cg = ufs_inotocg (ino);
+	bit = ufs_inotocgoff (ino);
+	ucpi = ufs_load_cylinder (sb, cg);
+	if (!ucpi) {
+		unlock_super (sb);
+		return;
+	}
+	ucg = ubh_get_ucg(UCPI_UBH);
+	if (!ufs_cg_chkmagic(ucg))
+		ufs_panic (sb, "ufs_free_fragments", "internal error, bad cg magic number");
+
+	UFSDM
+	
+	ucg->cg_time = SWAB32(CURRENT_TIME);
+
+	is_directory = S_ISDIR(inode->i_mode);
+
+	DQUOT_FREE_INODE(sb, inode);
+
+	clear_inode (inode);
+
+	if (ubh_isclr (UCPI_UBH, ucpi->c_iusedoff, bit))
+		ufs_error(sb, "ufs_free_inode", "bit already cleared for inode %u", ino);
+	else {
+		ubh_clrbit (UCPI_UBH, ucpi->c_iusedoff, bit);
+		if (ino < ucpi->c_irotor)
+			ucpi->c_irotor = ino;
+		INC_SWAB32(ucg->cg_cs.cs_nifree);
+		INC_SWAB32(usb1->fs_cstotal.cs_nifree);
+		INC_SWAB32(sb->fs_cs(cg).cs_nifree);
+
+		if (is_directory) {
+			DEC_SWAB32(ucg->cg_cs.cs_ndir);
+			DEC_SWAB32(usb1->fs_cstotal.cs_ndir);
+			DEC_SWAB32(sb->fs_cs(cg).cs_ndir);
+		}
+	}
+	ubh_mark_buffer_dirty (USPI_UBH, 1);
+	ubh_mark_buffer_dirty (UCPI_UBH, 1);
+	if (sb->s_flags & MS_SYNCHRONOUS) {
+		ubh_ll_rw_block (WRITE, 1, (struct ufs_buffer_head **) &ucpi);
+		ubh_wait_on_buffer (UCPI_UBH);
+	}
+	
+	UFSDM
+	
+	sb->s_dirt = 1;
+	unlock_super (sb);
+	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 (const struct inode * dir,	int mode, int * err )
+{
+	struct super_block * sb;
+	struct ufs_sb_private_info * uspi;
+	struct ufs_super_block_first * usb1;
+	struct ufs_cg_private_info * ucpi;
+	struct ufs_cylinder_group * ucg;
+	struct inode * inode;
+	unsigned cg, bit, i, j, start;
+	unsigned swab;
+
+	UFSD(("ENTER\n"))
+	
+	/* Cannot create files in a deleted directory */
+	if (!dir || !dir->i_nlink) {
+		*err = -EPERM;
+		return NULL;
+	}
+	inode = get_empty_inode ();
+	if (!inode) {
+		*err = -ENOMEM;
+		return NULL;
+	}
+	sb = dir->i_sb;
+	swab = sb->u.ufs_sb.s_swab;
+	uspi = sb->u.ufs_sb.s_uspi;
+	usb1 = ubh_get_usb_first(USPI_UBH);
+
+	inode->i_sb = sb;
+	inode->i_flags = sb->s_flags;
+	
+	lock_super (sb);
+
+	*err = -ENOSPC;
+
+	/*
+	 * Try to place the inode in its parent directory
+	 */
+	i = ufs_inotocg(dir->i_ino);
+	if (SWAB32(sb->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 (SWAB32(sb->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 (SWAB32(sb->fs_cs(i).cs_nifree)) {
+			cg = i;
+			goto cg_found;
+		}
+	}
+	
+	goto failed;
+
+cg_found:
+	ucpi = ufs_load_cylinder (sb, cg);
+	if (!ucpi)
+		goto failed;
+	ucg = ubh_get_ucg(UCPI_UBH);
+	if (!ufs_cg_chkmagic(ucg)) 
+		ufs_panic (sb, "ufs_new_inode", "internal error, bad cg magic number");
+
+	UFSDM
+	
+	start = ucpi->c_irotor;
+	bit = ubh_find_next_zero_bit (UCPI_UBH, ucpi->c_iusedoff, uspi->s_ipg, start);
+	if (!(bit < uspi->s_ipg)) {
+		bit = ubh_find_first_zero_bit (UCPI_UBH, ucpi->c_iusedoff, start);
+		if (!(bit < start)) {
+			ufs_error (sb, "ufs_new_inode",
+			    "cylinder group %u corrupted - error in inode bitmap\n", cg);
+			goto failed;
+		}
+	}
+	UFSD(("start = %u, bit = %u, ipg = %u\n", start, bit, uspi->s_ipg))
+	if (ubh_isclr (UCPI_UBH, ucpi->c_iusedoff, bit))
+		ubh_setbit (UCPI_UBH, ucpi->c_iusedoff, bit);
+	else {
+		ufs_panic (sb, "ufs_new_inode", "internal error");
+		goto failed;
+	}
+	
+	DEC_SWAB32(ucg->cg_cs.cs_nifree);
+	DEC_SWAB32(usb1->fs_cstotal.cs_nifree);
+	DEC_SWAB32(sb->fs_cs(cg).cs_nifree);
+	
+	if (S_ISDIR(mode)) {
+		INC_SWAB32(ucg->cg_cs.cs_ndir);
+		INC_SWAB32(usb1->fs_cstotal.cs_ndir);
+		INC_SWAB32(sb->fs_cs(cg).cs_ndir);
+	}
+
+	ubh_mark_buffer_dirty (USPI_UBH, 1);
+	ubh_mark_buffer_dirty (UCPI_UBH, 1);
+	if (sb->s_flags & MS_SYNCHRONOUS) {
+		ubh_ll_rw_block (WRITE, 1, (struct ufs_buffer_head **) &ucpi);
+		ubh_wait_on_buffer (UCPI_UBH);
+	}
+	sb->s_dirt = 1;
+
+	inode->i_mode = mode;
+	inode->i_sb = sb;
+	inode->i_nlink = 1;
+	inode->i_dev = sb->s_dev;
+	inode->i_uid = current->fsuid;
+	if (test_opt (sb, GRPID))
+		inode->i_gid = dir->i_gid;
+	else if (dir->i_mode & S_ISGID) {
+		inode->i_gid = dir->i_gid;
+		if (S_ISDIR(mode))
+			mode |= S_ISGID;
+	} else
+		inode->i_gid = current->fsgid;
+
+	inode->i_ino = cg * uspi->s_ipg + bit;
+	inode->i_blksize = PAGE_SIZE;	/* This is the optimal IO size (for stat), not the fs block size */
+	inode->i_blocks = 0;
+	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
+	inode->u.ufs_i.i_flags = dir->u.ufs_i.i_flags;
+	inode->u.ufs_i.i_uid = inode->i_uid;
+	inode->u.ufs_i.i_gid = inode->i_gid;
+	inode->u.ufs_i.i_lastfrag = 0;
+	inode->i_op = NULL;
+
+	insert_inode_hash(inode);
+	mark_inode_dirty(inode);
+
+	UFSDM
+	
+	unlock_super (sb);
+
+	if(DQUOT_ALLOC_INODE(sb, inode)) {
+		sb->dq_op->drop(inode);
+		inode->i_nlink = 0;
+		iput(inode);
+		*err = -EDQUOT;
+		return NULL;
+	}
+
+	UFSD(("allocating inode %lu\n", inode->i_ino))
+	*err = 0;
+	UFSD(("EXIT\n"))
+	return inode;
+
+failed:
+	unlock_super (sb);
+	iput (inode);
+	UFSD(("EXIT (FAILED)\n"))
+	return NULL;
+}