patch-2.4.20 linux-2.4.20/fs/jfs/jfs_dtree.c
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- Lines: 4664
- Date:
Thu Nov 28 15:53:15 2002
- Orig file:
linux-2.4.19/fs/jfs/jfs_dtree.c
- Orig date:
Wed Dec 31 16:00:00 1969
diff -urN linux-2.4.19/fs/jfs/jfs_dtree.c linux-2.4.20/fs/jfs/jfs_dtree.c
@@ -0,0 +1,4663 @@
+/*
+ * Copyright (c) International Business Machines Corp., 2000-2002
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will 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 to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+/*
+ * jfs_dtree.c: directory B+-tree manager
+ *
+ * B+-tree with variable length key directory:
+ *
+ * each directory page is structured as an array of 32-byte
+ * directory entry slots initialized as a freelist
+ * to avoid search/compaction of free space at insertion.
+ * when an entry is inserted, a number of slots are allocated
+ * from the freelist as required to store variable length data
+ * of the entry; when the entry is deleted, slots of the entry
+ * are returned to freelist.
+ *
+ * leaf entry stores full name as key and file serial number
+ * (aka inode number) as data.
+ * internal/router entry stores sufffix compressed name
+ * as key and simple extent descriptor as data.
+ *
+ * each directory page maintains a sorted entry index table
+ * which stores the start slot index of sorted entries
+ * to allow binary search on the table.
+ *
+ * directory starts as a root/leaf page in on-disk inode
+ * inline data area.
+ * when it becomes full, it starts a leaf of a external extent
+ * of length of 1 block. each time the first leaf becomes full,
+ * it is extended rather than split (its size is doubled),
+ * until its length becoms 4 KBytes, from then the extent is split
+ * with new 4 Kbyte extent when it becomes full
+ * to reduce external fragmentation of small directories.
+ *
+ * blah, blah, blah, for linear scan of directory in pieces by
+ * readdir().
+ *
+ *
+ * case-insensitive directory file system
+ *
+ * names are stored in case-sensitive way in leaf entry.
+ * but stored, searched and compared in case-insensitive (uppercase) order
+ * (i.e., both search key and entry key are folded for search/compare):
+ * (note that case-sensitive order is BROKEN in storage, e.g.,
+ * sensitive: Ad, aB, aC, aD -> insensitive: aB, aC, aD, Ad
+ *
+ * entries which folds to the same key makes up a equivalent class
+ * whose members are stored as contiguous cluster (may cross page boundary)
+ * but whose order is arbitrary and acts as duplicate, e.g.,
+ * abc, Abc, aBc, abC)
+ *
+ * once match is found at leaf, requires scan forward/backward
+ * either for, in case-insensitive search, duplicate
+ * or for, in case-sensitive search, for exact match
+ *
+ * router entry must be created/stored in case-insensitive way
+ * in internal entry:
+ * (right most key of left page and left most key of right page
+ * are folded, and its suffix compression is propagated as router
+ * key in parent)
+ * (e.g., if split occurs <abc> and <aBd>, <ABD> trather than <aB>
+ * should be made the router key for the split)
+ *
+ * case-insensitive search:
+ *
+ * fold search key;
+ *
+ * case-insensitive search of B-tree:
+ * for internal entry, router key is already folded;
+ * for leaf entry, fold the entry key before comparison.
+ *
+ * if (leaf entry case-insensitive match found)
+ * if (next entry satisfies case-insensitive match)
+ * return EDUPLICATE;
+ * if (prev entry satisfies case-insensitive match)
+ * return EDUPLICATE;
+ * return match;
+ * else
+ * return no match;
+ *
+ * serialization:
+ * target directory inode lock is being held on entry/exit
+ * of all main directory service routines.
+ *
+ * log based recovery:
+ */
+
+#include <linux/fs.h>
+#include "jfs_incore.h"
+#include "jfs_superblock.h"
+#include "jfs_filsys.h"
+#include "jfs_metapage.h"
+#include "jfs_dmap.h"
+#include "jfs_unicode.h"
+#include "jfs_debug.h"
+
+/* dtree split parameter */
+struct dtsplit {
+ struct metapage *mp;
+ s16 index;
+ s16 nslot;
+ struct component_name *key;
+ ddata_t *data;
+ struct pxdlist *pxdlist;
+};
+
+#define DT_PAGE(IP, MP) BT_PAGE(IP, MP, dtpage_t, i_dtroot)
+
+/* get page buffer for specified block address */
+#define DT_GETPAGE(IP, BN, MP, SIZE, P, RC)\
+{\
+ BT_GETPAGE(IP, BN, MP, dtpage_t, SIZE, P, RC, i_dtroot)\
+ if (!(RC))\
+ {\
+ if (((P)->header.nextindex > (((BN)==0)?DTROOTMAXSLOT:(P)->header.maxslot)) ||\
+ ((BN) && ((P)->header.maxslot > DTPAGEMAXSLOT)))\
+ {\
+ jERROR(1,("DT_GETPAGE: dtree page corrupt\n"));\
+ BT_PUTPAGE(MP);\
+ updateSuper((IP)->i_sb, FM_DIRTY);\
+ MP = NULL;\
+ RC = EIO;\
+ }\
+ }\
+}
+
+/* for consistency */
+#define DT_PUTPAGE(MP) BT_PUTPAGE(MP)
+
+#define DT_GETSEARCH(IP, LEAF, BN, MP, P, INDEX) \
+ BT_GETSEARCH(IP, LEAF, BN, MP, dtpage_t, P, INDEX, i_dtroot)
+
+/*
+ * forward references
+ */
+static int dtSplitUp(tid_t tid, struct inode *ip,
+ struct dtsplit * split, struct btstack * btstack);
+
+static int dtSplitPage(tid_t tid, struct inode *ip, struct dtsplit * split,
+ struct metapage ** rmpp, dtpage_t ** rpp, pxd_t * rxdp);
+
+static int dtExtendPage(tid_t tid, struct inode *ip,
+ struct dtsplit * split, struct btstack * btstack);
+
+static int dtSplitRoot(tid_t tid, struct inode *ip,
+ struct dtsplit * split, struct metapage ** rmpp);
+
+static int dtDeleteUp(tid_t tid, struct inode *ip, struct metapage * fmp,
+ dtpage_t * fp, struct btstack * btstack);
+
+static int dtSearchNode(struct inode *ip,
+ s64 lmxaddr, pxd_t * kpxd, struct btstack * btstack);
+
+static int dtRelink(tid_t tid, struct inode *ip, dtpage_t * p);
+
+static int dtReadFirst(struct inode *ip, struct btstack * btstack);
+
+static int dtReadNext(struct inode *ip,
+ loff_t * offset, struct btstack * btstack);
+
+static int dtCompare(struct component_name * key, dtpage_t * p, int si);
+
+static int ciCompare(struct component_name * key, dtpage_t * p, int si,
+ int flag);
+
+static void dtGetKey(dtpage_t * p, int i, struct component_name * key,
+ int flag);
+
+static void ciGetLeafPrefixKey(dtpage_t * lp, int li, dtpage_t * rp,
+ int ri, struct component_name * key, int flag);
+
+static void dtInsertEntry(dtpage_t * p, int index, struct component_name * key,
+ ddata_t * data, struct dt_lock **);
+
+static void dtMoveEntry(dtpage_t * sp, int si, dtpage_t * dp,
+ struct dt_lock ** sdtlock, struct dt_lock ** ddtlock,
+ int do_index);
+
+static void dtDeleteEntry(dtpage_t * p, int fi, struct dt_lock ** dtlock);
+
+static void dtTruncateEntry(dtpage_t * p, int ti, struct dt_lock ** dtlock);
+
+static void dtLinelockFreelist(dtpage_t * p, int m, struct dt_lock ** dtlock);
+
+#define ciToUpper(c) UniStrupr((c)->name)
+
+/*
+ * find_index()
+ *
+ * Returns dtree page containing directory table entry for specified
+ * index and pointer to its entry.
+ *
+ * mp must be released by caller.
+ */
+static struct dir_table_slot *find_index(struct inode *ip, u32 index,
+ struct metapage ** mp)
+{
+ struct jfs_inode_info *jfs_ip = JFS_IP(ip);
+ s64 blkno;
+ s64 offset;
+ int page_offset;
+ struct dir_table_slot *slot;
+ static int maxWarnings = 10;
+
+ if (index < 2) {
+ if (maxWarnings) {
+ jERROR(1, ("find_entry called with index = %d\n",
+ index));
+ maxWarnings--;
+ }
+ return 0;
+ }
+
+ if (index >= jfs_ip->next_index) {
+ jFYI(1, ("find_entry called with index >= next_index\n"));
+ return 0;
+ }
+
+ if (jfs_ip->next_index <= (MAX_INLINE_DIRTABLE_ENTRY + 1)) {
+ /*
+ * Inline directory table
+ */
+ *mp = 0;
+ slot = &jfs_ip->i_dirtable[index - 2];
+ } else {
+ offset = (index - 2) * sizeof(struct dir_table_slot);
+ page_offset = offset & (PSIZE - 1);
+ blkno = ((offset + 1) >> L2PSIZE) <<
+ JFS_SBI(ip->i_sb)->l2nbperpage;
+
+ if (*mp && ((*mp)->index != blkno)) {
+ release_metapage(*mp);
+ *mp = 0;
+ }
+ if (*mp == 0)
+ *mp = read_metapage(ip, blkno, PSIZE, 0);
+ if (*mp == 0) {
+ jERROR(1,
+ ("free_index: error reading directory table\n"));
+ return 0;
+ }
+
+ slot =
+ (struct dir_table_slot *) ((char *) (*mp)->data +
+ page_offset);
+ }
+ return slot;
+}
+
+static inline void lock_index(tid_t tid, struct inode *ip, struct metapage * mp,
+ u32 index)
+{
+ struct tlock *tlck;
+ struct linelock *llck;
+ struct lv *lv;
+
+ tlck = txLock(tid, ip, mp, tlckDATA);
+ llck = (struct linelock *) tlck->lock;
+
+ if (llck->index >= llck->maxcnt)
+ llck = txLinelock(llck);
+ lv = &llck->lv[llck->index];
+
+ /*
+ * Linelock slot size is twice the size of directory table
+ * slot size. 512 entries per page.
+ */
+ lv->offset = ((index - 2) & 511) >> 1;
+ lv->length = 1;
+ llck->index++;
+}
+
+/*
+ * add_index()
+ *
+ * Adds an entry to the directory index table. This is used to provide
+ * each directory entry with a persistent index in which to resume
+ * directory traversals
+ */
+static u32 add_index(tid_t tid, struct inode *ip, s64 bn, int slot)
+{
+ struct super_block *sb = ip->i_sb;
+ struct jfs_sb_info *sbi = JFS_SBI(sb);
+ struct jfs_inode_info *jfs_ip = JFS_IP(ip);
+ u64 blkno;
+ struct dir_table_slot *dirtab_slot;
+ u32 index;
+ struct linelock *llck;
+ struct lv *lv;
+ struct metapage *mp;
+ s64 offset;
+ uint page_offset;
+ int rc;
+ struct tlock *tlck;
+ s64 xaddr;
+
+ ASSERT(DO_INDEX(ip));
+
+ if (jfs_ip->next_index < 2) {
+ jERROR(1, ("next_index = %d. Please fix this!\n",
+ jfs_ip->next_index));
+ jfs_ip->next_index = 2;
+ }
+
+ index = jfs_ip->next_index++;
+
+ if (index <= MAX_INLINE_DIRTABLE_ENTRY) {
+ /*
+ * i_size reflects size of index table, or 8 bytes per entry.
+ */
+ ip->i_size = (loff_t) (index - 1) << 3;
+
+ /*
+ * dir table fits inline within inode
+ */
+ dirtab_slot = &jfs_ip->i_dirtable[index-2];
+ dirtab_slot->flag = DIR_INDEX_VALID;
+ dirtab_slot->slot = slot;
+ DTSaddress(dirtab_slot, bn);
+
+ set_cflag(COMMIT_Dirtable, ip);
+
+ return index;
+ }
+ if (index == (MAX_INLINE_DIRTABLE_ENTRY + 1)) {
+ /*
+ * It's time to move the inline table to an external
+ * page and begin to build the xtree
+ */
+
+ /*
+ * Save the table, we're going to overwrite it with the
+ * xtree root
+ */
+ struct dir_table_slot temp_table[12];
+ memcpy(temp_table, &jfs_ip->i_dirtable, sizeof(temp_table));
+
+ /*
+ * Initialize empty x-tree
+ */
+ xtInitRoot(tid, ip);
+
+ /*
+ * Allocate the first block & add it to the xtree
+ */
+ xaddr = 0;
+ if ((rc =
+ xtInsert(tid, ip, 0, 0, sbi->nbperpage,
+ &xaddr, 0))) {
+ jFYI(1, ("add_index: xtInsert failed!\n"));
+ return -1;
+ }
+ ip->i_size = PSIZE;
+ ip->i_blocks += LBLK2PBLK(sb, sbi->nbperpage);
+
+ if ((mp = get_metapage(ip, 0, ip->i_blksize, 0)) == 0) {
+ jERROR(1, ("add_index: get_metapage failed!\n"));
+ xtTruncate(tid, ip, 0, COMMIT_PWMAP);
+ return -1;
+ }
+ tlck = txLock(tid, ip, mp, tlckDATA);
+ llck = (struct linelock *) & tlck->lock;
+ ASSERT(llck->index == 0);
+ lv = &llck->lv[0];
+
+ lv->offset = 0;
+ lv->length = 6; /* tlckDATA slot size is 16 bytes */
+ llck->index++;
+
+ memcpy(mp->data, temp_table, sizeof(temp_table));
+
+ mark_metapage_dirty(mp);
+ release_metapage(mp);
+
+ /*
+ * Logging is now directed by xtree tlocks
+ */
+ clear_cflag(COMMIT_Dirtable, ip);
+ }
+
+ offset = (index - 2) * sizeof(struct dir_table_slot);
+ page_offset = offset & (PSIZE - 1);
+ blkno = ((offset + 1) >> L2PSIZE) << sbi->l2nbperpage;
+ if (page_offset == 0) {
+ /*
+ * This will be the beginning of a new page
+ */
+ xaddr = 0;
+ if ((rc =
+ xtInsert(tid, ip, 0, blkno, sbi->nbperpage,
+ &xaddr, 0))) {
+ jFYI(1, ("add_index: xtInsert failed!\n"));
+ jfs_ip->next_index--;
+ return -1;
+ }
+ ip->i_size += PSIZE;
+ ip->i_blocks += LBLK2PBLK(sb, sbi->nbperpage);
+
+ if ((mp = get_metapage(ip, blkno, PSIZE, 0)))
+ memset(mp->data, 0, PSIZE); /* Just looks better */
+ else
+ xtTruncate(tid, ip, offset, COMMIT_PWMAP);
+ } else
+ mp = read_metapage(ip, blkno, PSIZE, 0);
+
+ if (mp == 0) {
+ jERROR(1, ("add_index: get/read_metapage failed!\n"));
+ return -1;
+ }
+
+ lock_index(tid, ip, mp, index);
+
+ dirtab_slot =
+ (struct dir_table_slot *) ((char *) mp->data + page_offset);
+ dirtab_slot->flag = DIR_INDEX_VALID;
+ dirtab_slot->slot = slot;
+ DTSaddress(dirtab_slot, bn);
+
+ mark_metapage_dirty(mp);
+ release_metapage(mp);
+
+ return index;
+}
+
+/*
+ * free_index()
+ *
+ * Marks an entry to the directory index table as free.
+ */
+static void free_index(tid_t tid, struct inode *ip, u32 index, u32 next)
+{
+ struct dir_table_slot *dirtab_slot;
+ struct metapage *mp = 0;
+
+ dirtab_slot = find_index(ip, index, &mp);
+
+ if (dirtab_slot == 0)
+ return;
+
+ dirtab_slot->flag = DIR_INDEX_FREE;
+ dirtab_slot->slot = dirtab_slot->addr1 = 0;
+ dirtab_slot->addr2 = cpu_to_le32(next);
+
+ if (mp) {
+ lock_index(tid, ip, mp, index);
+ mark_metapage_dirty(mp);
+ release_metapage(mp);
+ } else
+ set_cflag(COMMIT_Dirtable, ip);
+}
+
+/*
+ * modify_index()
+ *
+ * Changes an entry in the directory index table
+ */
+static void modify_index(tid_t tid, struct inode *ip, u32 index, s64 bn,
+ int slot, struct metapage ** mp)
+{
+ struct dir_table_slot *dirtab_slot;
+
+ dirtab_slot = find_index(ip, index, mp);
+
+ if (dirtab_slot == 0)
+ return;
+
+ DTSaddress(dirtab_slot, bn);
+ dirtab_slot->slot = slot;
+
+ if (*mp) {
+ lock_index(tid, ip, *mp, index);
+ mark_metapage_dirty(*mp);
+ } else
+ set_cflag(COMMIT_Dirtable, ip);
+}
+
+/*
+ * read_index()
+ *
+ * reads a directory table slot
+ */
+static int read_index(struct inode *ip, u32 index,
+ struct dir_table_slot * dirtab_slot)
+{
+ struct metapage *mp = 0;
+ struct dir_table_slot *slot;
+
+ slot = find_index(ip, index, &mp);
+ if (slot == 0) {
+ return -EIO;
+ }
+
+ memcpy(dirtab_slot, slot, sizeof(struct dir_table_slot));
+
+ if (mp)
+ release_metapage(mp);
+
+ return 0;
+}
+
+/*
+ * dtSearch()
+ *
+ * function:
+ * Search for the entry with specified key
+ *
+ * parameter:
+ *
+ * return: 0 - search result on stack, leaf page pinned;
+ * errno - I/O error
+ */
+int dtSearch(struct inode *ip, struct component_name * key, ino_t * data,
+ struct btstack * btstack, int flag)
+{
+ int rc = 0;
+ int cmp = 1; /* init for empty page */
+ s64 bn;
+ struct metapage *mp;
+ dtpage_t *p;
+ s8 *stbl;
+ int base, index, lim;
+ struct btframe *btsp;
+ pxd_t *pxd;
+ int psize = 288; /* initial in-line directory */
+ ino_t inumber;
+ struct component_name ciKey;
+ struct super_block *sb = ip->i_sb;
+
+ ciKey.name =
+ (wchar_t *) kmalloc((JFS_NAME_MAX + 1) * sizeof(wchar_t),
+ GFP_NOFS);
+ if (ciKey.name == 0) {
+ rc = ENOMEM;
+ goto dtSearch_Exit2;
+ }
+
+
+ /* uppercase search key for c-i directory */
+ UniStrcpy(ciKey.name, key->name);
+ ciKey.namlen = key->namlen;
+
+ /* only uppercase if case-insensitive support is on */
+ if ((JFS_SBI(sb)->mntflag & JFS_OS2) == JFS_OS2) {
+ ciToUpper(&ciKey);
+ }
+ BT_CLR(btstack); /* reset stack */
+
+ /* init level count for max pages to split */
+ btstack->nsplit = 1;
+
+ /*
+ * search down tree from root:
+ *
+ * between two consecutive entries of <Ki, Pi> and <Kj, Pj> of
+ * internal page, child page Pi contains entry with k, Ki <= K < Kj.
+ *
+ * if entry with search key K is not found
+ * internal page search find the entry with largest key Ki
+ * less than K which point to the child page to search;
+ * leaf page search find the entry with smallest key Kj
+ * greater than K so that the returned index is the position of
+ * the entry to be shifted right for insertion of new entry.
+ * for empty tree, search key is greater than any key of the tree.
+ *
+ * by convention, root bn = 0.
+ */
+ for (bn = 0;;) {
+ /* get/pin the page to search */
+ DT_GETPAGE(ip, bn, mp, psize, p, rc);
+ if (rc)
+ goto dtSearch_Exit1;
+
+ /* get sorted entry table of the page */
+ stbl = DT_GETSTBL(p);
+
+ /*
+ * binary search with search key K on the current page.
+ */
+ for (base = 0, lim = p->header.nextindex; lim; lim >>= 1) {
+ index = base + (lim >> 1);
+
+ if (p->header.flag & BT_LEAF) {
+ /* uppercase leaf name to compare */
+ cmp =
+ ciCompare(&ciKey, p, stbl[index],
+ JFS_SBI(sb)->mntflag);
+ } else {
+ /* router key is in uppercase */
+
+ cmp = dtCompare(&ciKey, p, stbl[index]);
+
+
+ }
+ if (cmp == 0) {
+ /*
+ * search hit
+ */
+ /* search hit - leaf page:
+ * return the entry found
+ */
+ if (p->header.flag & BT_LEAF) {
+ inumber = le32_to_cpu(
+ ((struct ldtentry *) & p->slot[stbl[index]])->inumber);
+
+ /*
+ * search for JFS_LOOKUP
+ */
+ if (flag == JFS_LOOKUP) {
+ *data = inumber;
+ rc = 0;
+ goto out;
+ }
+
+ /*
+ * search for JFS_CREATE
+ */
+ if (flag == JFS_CREATE) {
+ *data = inumber;
+ rc = EEXIST;
+ goto out;
+ }
+
+ /*
+ * search for JFS_REMOVE or JFS_RENAME
+ */
+ if ((flag == JFS_REMOVE ||
+ flag == JFS_RENAME) &&
+ *data != inumber) {
+ rc = ESTALE;
+ goto out;
+ }
+
+ /*
+ * JFS_REMOVE|JFS_FINDDIR|JFS_RENAME
+ */
+ /* save search result */
+ *data = inumber;
+ btsp = btstack->top;
+ btsp->bn = bn;
+ btsp->index = index;
+ btsp->mp = mp;
+
+ rc = 0;
+ goto dtSearch_Exit1;
+ }
+
+ /* search hit - internal page:
+ * descend/search its child page
+ */
+ goto getChild;
+ }
+
+ if (cmp > 0) {
+ base = index + 1;
+ --lim;
+ }
+ }
+
+ /*
+ * search miss
+ *
+ * base is the smallest index with key (Kj) greater than
+ * search key (K) and may be zero or (maxindex + 1) index.
+ */
+ /*
+ * search miss - leaf page
+ *
+ * return location of entry (base) where new entry with
+ * search key K is to be inserted.
+ */
+ if (p->header.flag & BT_LEAF) {
+ /*
+ * search for JFS_LOOKUP, JFS_REMOVE, or JFS_RENAME
+ */
+ if (flag == JFS_LOOKUP || flag == JFS_REMOVE ||
+ flag == JFS_RENAME) {
+ rc = ENOENT;
+ goto out;
+ }
+
+ /*
+ * search for JFS_CREATE|JFS_FINDDIR:
+ *
+ * save search result
+ */
+ *data = 0;
+ btsp = btstack->top;
+ btsp->bn = bn;
+ btsp->index = base;
+ btsp->mp = mp;
+
+ rc = 0;
+ goto dtSearch_Exit1;
+ }
+
+ /*
+ * search miss - internal page
+ *
+ * if base is non-zero, decrement base by one to get the parent
+ * entry of the child page to search.
+ */
+ index = base ? base - 1 : base;
+
+ /*
+ * go down to child page
+ */
+ getChild:
+ /* update max. number of pages to split */
+ if (btstack->nsplit >= 8) {
+ /* Something's corrupted, mark filesytem dirty so
+ * chkdsk will fix it.
+ */
+ jERROR(1, ("stack overrun in dtSearch!\n"));
+ updateSuper(sb, FM_DIRTY);
+ rc = EIO;
+ goto out;
+ }
+ btstack->nsplit++;
+
+ /* push (bn, index) of the parent page/entry */
+ BT_PUSH(btstack, bn, index);
+
+ /* get the child page block number */
+ pxd = (pxd_t *) & p->slot[stbl[index]];
+ bn = addressPXD(pxd);
+ psize = lengthPXD(pxd) << JFS_SBI(ip->i_sb)->l2bsize;
+
+ /* unpin the parent page */
+ DT_PUTPAGE(mp);
+ }
+
+ out:
+ DT_PUTPAGE(mp);
+
+ dtSearch_Exit1:
+
+ kfree(ciKey.name);
+
+ dtSearch_Exit2:
+
+ return rc;
+}
+
+
+/*
+ * dtInsert()
+ *
+ * function: insert an entry to directory tree
+ *
+ * parameter:
+ *
+ * return: 0 - success;
+ * errno - failure;
+ */
+int dtInsert(tid_t tid, struct inode *ip,
+ struct component_name * name, ino_t * fsn, struct btstack * btstack)
+{
+ int rc = 0;
+ struct metapage *mp; /* meta-page buffer */
+ dtpage_t *p; /* base B+-tree index page */
+ s64 bn;
+ int index;
+ struct dtsplit split; /* split information */
+ ddata_t data;
+ struct dt_lock *dtlck;
+ int n;
+ struct tlock *tlck;
+ struct lv *lv;
+
+ /*
+ * retrieve search result
+ *
+ * dtSearch() returns (leaf page pinned, index at which to insert).
+ * n.b. dtSearch() may return index of (maxindex + 1) of
+ * the full page.
+ */
+ DT_GETSEARCH(ip, btstack->top, bn, mp, p, index);
+
+ /*
+ * insert entry for new key
+ */
+ if (DO_INDEX(ip)) {
+ if (JFS_IP(ip)->next_index == DIREND) {
+ DT_PUTPAGE(mp);
+ return EMLINK;
+ }
+ n = NDTLEAF(name->namlen);
+ data.leaf.tid = tid;
+ data.leaf.ip = ip;
+ } else {
+ n = NDTLEAF_LEGACY(name->namlen);
+ data.leaf.ip = 0; /* signifies legacy directory format */
+ }
+ data.leaf.ino = cpu_to_le32(*fsn);
+
+ /*
+ * leaf page does not have enough room for new entry:
+ *
+ * extend/split the leaf page;
+ *
+ * dtSplitUp() will insert the entry and unpin the leaf page.
+ */
+ if (n > p->header.freecnt) {
+ split.mp = mp;
+ split.index = index;
+ split.nslot = n;
+ split.key = name;
+ split.data = &data;
+ rc = dtSplitUp(tid, ip, &split, btstack);
+ return rc;
+ }
+
+ /*
+ * leaf page does have enough room for new entry:
+ *
+ * insert the new data entry into the leaf page;
+ */
+ BT_MARK_DIRTY(mp, ip);
+ /*
+ * acquire a transaction lock on the leaf page
+ */
+ tlck = txLock(tid, ip, mp, tlckDTREE | tlckENTRY);
+ dtlck = (struct dt_lock *) & tlck->lock;
+ ASSERT(dtlck->index == 0);
+ lv = & dtlck->lv[0];
+
+ /* linelock header */
+ lv->offset = 0;
+ lv->length = 1;
+ dtlck->index++;
+
+ dtInsertEntry(p, index, name, &data, &dtlck);
+
+ /* linelock stbl of non-root leaf page */
+ if (!(p->header.flag & BT_ROOT)) {
+ if (dtlck->index >= dtlck->maxcnt)
+ dtlck = (struct dt_lock *) txLinelock(dtlck);
+ lv = & dtlck->lv[dtlck->index];
+ n = index >> L2DTSLOTSIZE;
+ lv->offset = p->header.stblindex + n;
+ lv->length =
+ ((p->header.nextindex - 1) >> L2DTSLOTSIZE) - n + 1;
+ dtlck->index++;
+ }
+
+ /* unpin the leaf page */
+ DT_PUTPAGE(mp);
+
+ return 0;
+}
+
+
+/*
+ * dtSplitUp()
+ *
+ * function: propagate insertion bottom up;
+ *
+ * parameter:
+ *
+ * return: 0 - success;
+ * errno - failure;
+ * leaf page unpinned;
+ */
+static int dtSplitUp(tid_t tid,
+ struct inode *ip, struct dtsplit * split, struct btstack * btstack)
+{
+ struct jfs_sb_info *sbi = JFS_SBI(ip->i_sb);
+ int rc = 0;
+ struct metapage *smp;
+ dtpage_t *sp; /* split page */
+ struct metapage *rmp;
+ dtpage_t *rp; /* new right page split from sp */
+ pxd_t rpxd; /* new right page extent descriptor */
+ struct metapage *lmp;
+ dtpage_t *lp; /* left child page */
+ int skip; /* index of entry of insertion */
+ struct btframe *parent; /* parent page entry on traverse stack */
+ s64 xaddr, nxaddr;
+ int xlen, xsize;
+ struct pxdlist pxdlist;
+ pxd_t *pxd;
+ struct component_name key = { 0, 0 };
+ ddata_t *data = split->data;
+ int n;
+ struct dt_lock *dtlck;
+ struct tlock *tlck;
+ struct lv *lv;
+
+ /* get split page */
+ smp = split->mp;
+ sp = DT_PAGE(ip, smp);
+
+ key.name =
+ (wchar_t *) kmalloc((JFS_NAME_MAX + 2) * sizeof(wchar_t),
+ GFP_NOFS);
+ if (key.name == 0) {
+ DT_PUTPAGE(smp);
+ rc = ENOMEM;
+ goto dtSplitUp_Exit;
+ }
+
+ /*
+ * split leaf page
+ *
+ * The split routines insert the new entry, and
+ * acquire txLock as appropriate.
+ */
+ /*
+ * split root leaf page:
+ */
+ if (sp->header.flag & BT_ROOT) {
+ /*
+ * allocate a single extent child page
+ */
+ xlen = 1;
+ n = sbi->bsize >> L2DTSLOTSIZE;
+ n -= (n + 31) >> L2DTSLOTSIZE; /* stbl size */
+ n -= DTROOTMAXSLOT - sp->header.freecnt; /* header + entries */
+ if (n <= split->nslot)
+ xlen++;
+ if ((rc = dbAlloc(ip, 0, (s64) xlen, &xaddr)))
+ goto freeKeyName;
+
+ pxdlist.maxnpxd = 1;
+ pxdlist.npxd = 0;
+ pxd = &pxdlist.pxd[0];
+ PXDaddress(pxd, xaddr);
+ PXDlength(pxd, xlen);
+ split->pxdlist = &pxdlist;
+ rc = dtSplitRoot(tid, ip, split, &rmp);
+
+ DT_PUTPAGE(rmp);
+ DT_PUTPAGE(smp);
+
+ goto freeKeyName;
+ }
+
+ /*
+ * extend first leaf page
+ *
+ * extend the 1st extent if less than buffer page size
+ * (dtExtendPage() reurns leaf page unpinned)
+ */
+ pxd = &sp->header.self;
+ xlen = lengthPXD(pxd);
+ xsize = xlen << sbi->l2bsize;
+ if (xsize < PSIZE) {
+ xaddr = addressPXD(pxd);
+ n = xsize >> L2DTSLOTSIZE;
+ n -= (n + 31) >> L2DTSLOTSIZE; /* stbl size */
+ if ((n + sp->header.freecnt) <= split->nslot)
+ n = xlen + (xlen << 1);
+ else
+ n = xlen;
+ if ((rc = dbReAlloc(sbi->ipbmap, xaddr, (s64) xlen,
+ (s64) n, &nxaddr)))
+ goto extendOut;
+
+ pxdlist.maxnpxd = 1;
+ pxdlist.npxd = 0;
+ pxd = &pxdlist.pxd[0];
+ PXDaddress(pxd, nxaddr)
+ PXDlength(pxd, xlen + n);
+ split->pxdlist = &pxdlist;
+ if ((rc = dtExtendPage(tid, ip, split, btstack))) {
+ nxaddr = addressPXD(pxd);
+ if (xaddr != nxaddr) {
+ /* free relocated extent */
+ xlen = lengthPXD(pxd);
+ dbFree(ip, nxaddr, (s64) xlen);
+ } else {
+ /* free extended delta */
+ xlen = lengthPXD(pxd) - n;
+ xaddr = addressPXD(pxd) + xlen;
+ dbFree(ip, xaddr, (s64) n);
+ }
+ }
+
+ extendOut:
+ DT_PUTPAGE(smp);
+ goto freeKeyName;
+ }
+
+ /*
+ * split leaf page <sp> into <sp> and a new right page <rp>.
+ *
+ * return <rp> pinned and its extent descriptor <rpxd>
+ */
+ /*
+ * allocate new directory page extent and
+ * new index page(s) to cover page split(s)
+ *
+ * allocation hint: ?
+ */
+ n = btstack->nsplit;
+ pxdlist.maxnpxd = pxdlist.npxd = 0;
+ xlen = sbi->nbperpage;
+ for (pxd = pxdlist.pxd; n > 0; n--, pxd++) {
+ if ((rc = dbAlloc(ip, 0, (s64) xlen, &xaddr)) == 0) {
+ PXDaddress(pxd, xaddr);
+ PXDlength(pxd, xlen);
+ pxdlist.maxnpxd++;
+ continue;
+ }
+
+ DT_PUTPAGE(smp);
+
+ /* undo allocation */
+ goto splitOut;
+ }
+
+ split->pxdlist = &pxdlist;
+ if ((rc = dtSplitPage(tid, ip, split, &rmp, &rp, &rpxd))) {
+ DT_PUTPAGE(smp);
+
+ /* undo allocation */
+ goto splitOut;
+ }
+
+ /*
+ * propagate up the router entry for the leaf page just split
+ *
+ * insert a router entry for the new page into the parent page,
+ * propagate the insert/split up the tree by walking back the stack
+ * of (bn of parent page, index of child page entry in parent page)
+ * that were traversed during the search for the page that split.
+ *
+ * the propagation of insert/split up the tree stops if the root
+ * splits or the page inserted into doesn't have to split to hold
+ * the new entry.
+ *
+ * the parent entry for the split page remains the same, and
+ * a new entry is inserted at its right with the first key and
+ * block number of the new right page.
+ *
+ * There are a maximum of 4 pages pinned at any time:
+ * two children, left parent and right parent (when the parent splits).
+ * keep the child pages pinned while working on the parent.
+ * make sure that all pins are released at exit.
+ */
+ while ((parent = BT_POP(btstack)) != NULL) {
+ /* parent page specified by stack frame <parent> */
+
+ /* keep current child pages (<lp>, <rp>) pinned */
+ lmp = smp;
+ lp = sp;
+
+ /*
+ * insert router entry in parent for new right child page <rp>
+ */
+ /* get the parent page <sp> */
+ DT_GETPAGE(ip, parent->bn, smp, PSIZE, sp, rc);
+ if (rc) {
+ DT_PUTPAGE(lmp);
+ DT_PUTPAGE(rmp);
+ goto splitOut;
+ }
+
+ /*
+ * The new key entry goes ONE AFTER the index of parent entry,
+ * because the split was to the right.
+ */
+ skip = parent->index + 1;
+
+ /*
+ * compute the key for the router entry
+ *
+ * key suffix compression:
+ * for internal pages that have leaf pages as children,
+ * retain only what's needed to distinguish between
+ * the new entry and the entry on the page to its left.
+ * If the keys compare equal, retain the entire key.
+ *
+ * note that compression is performed only at computing
+ * router key at the lowest internal level.
+ * further compression of the key between pairs of higher
+ * level internal pages loses too much information and
+ * the search may fail.
+ * (e.g., two adjacent leaf pages of {a, ..., x} {xx, ...,}
+ * results in two adjacent parent entries (a)(xx).
+ * if split occurs between these two entries, and
+ * if compression is applied, the router key of parent entry
+ * of right page (x) will divert search for x into right
+ * subtree and miss x in the left subtree.)
+ *
+ * the entire key must be retained for the next-to-leftmost
+ * internal key at any level of the tree, or search may fail
+ * (e.g., ?)
+ */
+ switch (rp->header.flag & BT_TYPE) {
+ case BT_LEAF:
+ /*
+ * compute the length of prefix for suffix compression
+ * between last entry of left page and first entry
+ * of right page
+ */
+ if ((sp->header.flag & BT_ROOT && skip > 1) ||
+ sp->header.prev != 0 || skip > 1) {
+ /* compute uppercase router prefix key */
+ ciGetLeafPrefixKey(lp,
+ lp->header.nextindex - 1,
+ rp, 0, &key, sbi->mntflag);
+ } else {
+ /* next to leftmost entry of
+ lowest internal level */
+
+ /* compute uppercase router key */
+ dtGetKey(rp, 0, &key, sbi->mntflag);
+ key.name[key.namlen] = 0;
+
+ if ((sbi->mntflag & JFS_OS2) == JFS_OS2)
+ ciToUpper(&key);
+ }
+
+ n = NDTINTERNAL(key.namlen);
+ break;
+
+ case BT_INTERNAL:
+ dtGetKey(rp, 0, &key, sbi->mntflag);
+ n = NDTINTERNAL(key.namlen);
+ break;
+
+ default:
+ jERROR(2, ("dtSplitUp(): UFO!\n"));
+ break;
+ }
+
+ /* unpin left child page */
+ DT_PUTPAGE(lmp);
+
+ /*
+ * compute the data for the router entry
+ */
+ data->xd = rpxd; /* child page xd */
+
+ /*
+ * parent page is full - split the parent page
+ */
+ if (n > sp->header.freecnt) {
+ /* init for parent page split */
+ split->mp = smp;
+ split->index = skip; /* index at insert */
+ split->nslot = n;
+ split->key = &key;
+ /* split->data = data; */
+
+ /* unpin right child page */
+ DT_PUTPAGE(rmp);
+
+ /* The split routines insert the new entry,
+ * acquire txLock as appropriate.
+ * return <rp> pinned and its block number <rbn>.
+ */
+ rc = (sp->header.flag & BT_ROOT) ?
+ dtSplitRoot(tid, ip, split, &rmp) :
+ dtSplitPage(tid, ip, split, &rmp, &rp, &rpxd);
+ if (rc) {
+ DT_PUTPAGE(smp);
+ goto splitOut;
+ }
+
+ /* smp and rmp are pinned */
+ }
+ /*
+ * parent page is not full - insert router entry in parent page
+ */
+ else {
+ BT_MARK_DIRTY(smp, ip);
+ /*
+ * acquire a transaction lock on the parent page
+ */
+ tlck = txLock(tid, ip, smp, tlckDTREE | tlckENTRY);
+ dtlck = (struct dt_lock *) & tlck->lock;
+ ASSERT(dtlck->index == 0);
+ lv = & dtlck->lv[0];
+
+ /* linelock header */
+ lv->offset = 0;
+ lv->length = 1;
+ dtlck->index++;
+
+ /* linelock stbl of non-root parent page */
+ if (!(sp->header.flag & BT_ROOT)) {
+ lv++;
+ n = skip >> L2DTSLOTSIZE;
+ lv->offset = sp->header.stblindex + n;
+ lv->length =
+ ((sp->header.nextindex -
+ 1) >> L2DTSLOTSIZE) - n + 1;
+ dtlck->index++;
+ }
+
+ dtInsertEntry(sp, skip, &key, data, &dtlck);
+
+ /* exit propagate up */
+ break;
+ }
+ }
+
+ /* unpin current split and its right page */
+ DT_PUTPAGE(smp);
+ DT_PUTPAGE(rmp);
+
+ /*
+ * free remaining extents allocated for split
+ */
+ splitOut:
+ n = pxdlist.npxd;
+ pxd = &pxdlist.pxd[n];
+ for (; n < pxdlist.maxnpxd; n++, pxd++)
+ dbFree(ip, addressPXD(pxd), (s64) lengthPXD(pxd));
+
+ freeKeyName:
+ kfree(key.name);
+
+ dtSplitUp_Exit:
+
+ return rc;
+}
+
+
+/*
+ * dtSplitPage()
+ *
+ * function: Split a non-root page of a btree.
+ *
+ * parameter:
+ *
+ * return: 0 - success;
+ * errno - failure;
+ * return split and new page pinned;
+ */
+static int dtSplitPage(tid_t tid, struct inode *ip, struct dtsplit * split,
+ struct metapage ** rmpp, dtpage_t ** rpp, pxd_t * rpxdp)
+{
+ struct super_block *sb = ip->i_sb;
+ int rc = 0;
+ struct metapage *smp;
+ dtpage_t *sp;
+ struct metapage *rmp;
+ dtpage_t *rp; /* new right page allocated */
+ s64 rbn; /* new right page block number */
+ struct metapage *mp;
+ dtpage_t *p;
+ s64 nextbn;
+ struct pxdlist *pxdlist;
+ pxd_t *pxd;
+ int skip, nextindex, half, left, nxt, off, si;
+ struct ldtentry *ldtentry;
+ struct idtentry *idtentry;
+ u8 *stbl;
+ struct dtslot *f;
+ int fsi, stblsize;
+ int n;
+ struct dt_lock *sdtlck, *rdtlck;
+ struct tlock *tlck;
+ struct dt_lock *dtlck;
+ struct lv *slv, *rlv, *lv;
+
+ /* get split page */
+ smp = split->mp;
+ sp = DT_PAGE(ip, smp);
+
+ /*
+ * allocate the new right page for the split
+ */
+ pxdlist = split->pxdlist;
+ pxd = &pxdlist->pxd[pxdlist->npxd];
+ pxdlist->npxd++;
+ rbn = addressPXD(pxd);
+ rmp = get_metapage(ip, rbn, PSIZE, 1);
+ if (rmp == NULL)
+ return EIO;
+
+ jEVENT(0,
+ ("dtSplitPage: ip:0x%p smp:0x%p rmp:0x%p\n", ip, smp, rmp));
+
+ BT_MARK_DIRTY(rmp, ip);
+ /*
+ * acquire a transaction lock on the new right page
+ */
+ tlck = txLock(tid, ip, rmp, tlckDTREE | tlckNEW);
+ rdtlck = (struct dt_lock *) & tlck->lock;
+
+ rp = (dtpage_t *) rmp->data;
+ *rpp = rp;
+ rp->header.self = *pxd;
+
+ BT_MARK_DIRTY(smp, ip);
+ /*
+ * acquire a transaction lock on the split page
+ *
+ * action:
+ */
+ tlck = txLock(tid, ip, smp, tlckDTREE | tlckENTRY);
+ sdtlck = (struct dt_lock *) & tlck->lock;
+
+ /* linelock header of split page */
+ ASSERT(sdtlck->index == 0);
+ slv = & sdtlck->lv[0];
+ slv->offset = 0;
+ slv->length = 1;
+ sdtlck->index++;
+
+ /*
+ * initialize/update sibling pointers between sp and rp
+ */
+ nextbn = le64_to_cpu(sp->header.next);
+ rp->header.next = cpu_to_le64(nextbn);
+ rp->header.prev = cpu_to_le64(addressPXD(&sp->header.self));
+ sp->header.next = cpu_to_le64(rbn);
+
+ /*
+ * initialize new right page
+ */
+ rp->header.flag = sp->header.flag;
+
+ /* compute sorted entry table at start of extent data area */
+ rp->header.nextindex = 0;
+ rp->header.stblindex = 1;
+
+ n = PSIZE >> L2DTSLOTSIZE;
+ rp->header.maxslot = n;
+ stblsize = (n + 31) >> L2DTSLOTSIZE; /* in unit of slot */
+
+ /* init freelist */
+ fsi = rp->header.stblindex + stblsize;
+ rp->header.freelist = fsi;
+ rp->header.freecnt = rp->header.maxslot - fsi;
+
+ /*
+ * sequential append at tail: append without split
+ *
+ * If splitting the last page on a level because of appending
+ * a entry to it (skip is maxentry), it's likely that the access is
+ * sequential. Adding an empty page on the side of the level is less
+ * work and can push the fill factor much higher than normal.
+ * If we're wrong it's no big deal, we'll just do the split the right
+ * way next time.
+ * (It may look like it's equally easy to do a similar hack for
+ * reverse sorted data, that is, split the tree left,
+ * but it's not. Be my guest.)
+ */
+ if (nextbn == 0 && split->index == sp->header.nextindex) {
+ /* linelock header + stbl (first slot) of new page */
+ rlv = & rdtlck->lv[rdtlck->index];
+ rlv->offset = 0;
+ rlv->length = 2;
+ rdtlck->index++;
+
+ /*
+ * initialize freelist of new right page
+ */
+ f = &rp->slot[fsi];
+ for (fsi++; fsi < rp->header.maxslot; f++, fsi++)
+ f->next = fsi;
+ f->next = -1;
+
+ /* insert entry at the first entry of the new right page */
+ dtInsertEntry(rp, 0, split->key, split->data, &rdtlck);
+
+ goto out;
+ }
+
+ /*
+ * non-sequential insert (at possibly middle page)
+ */
+
+ /*
+ * update prev pointer of previous right sibling page;
+ */
+ if (nextbn != 0) {
+ DT_GETPAGE(ip, nextbn, mp, PSIZE, p, rc);
+ if (rc)
+ return rc;
+
+ BT_MARK_DIRTY(mp, ip);
+ /*
+ * acquire a transaction lock on the next page
+ */
+ tlck = txLock(tid, ip, mp, tlckDTREE | tlckRELINK);
+ jEVENT(0,
+ ("dtSplitPage: tlck = 0x%p, ip = 0x%p, mp=0x%p\n",
+ tlck, ip, mp));
+ dtlck = (struct dt_lock *) & tlck->lock;
+
+ /* linelock header of previous right sibling page */
+ lv = & dtlck->lv[dtlck->index];
+ lv->offset = 0;
+ lv->length = 1;
+ dtlck->index++;
+
+ p->header.prev = cpu_to_le64(rbn);
+
+ DT_PUTPAGE(mp);
+ }
+
+ /*
+ * split the data between the split and right pages.
+ */
+ skip = split->index;
+ half = (PSIZE >> L2DTSLOTSIZE) >> 1; /* swag */
+ left = 0;
+
+ /*
+ * compute fill factor for split pages
+ *
+ * <nxt> traces the next entry to move to rp
+ * <off> traces the next entry to stay in sp
+ */
+ stbl = (u8 *) & sp->slot[sp->header.stblindex];
+ nextindex = sp->header.nextindex;
+ for (nxt = off = 0; nxt < nextindex; ++off) {
+ if (off == skip)
+ /* check for fill factor with new entry size */
+ n = split->nslot;
+ else {
+ si = stbl[nxt];
+ switch (sp->header.flag & BT_TYPE) {
+ case BT_LEAF:
+ ldtentry = (struct ldtentry *) & sp->slot[si];
+ if (DO_INDEX(ip))
+ n = NDTLEAF(ldtentry->namlen);
+ else
+ n = NDTLEAF_LEGACY(ldtentry->
+ namlen);
+ break;
+
+ case BT_INTERNAL:
+ idtentry = (struct idtentry *) & sp->slot[si];
+ n = NDTINTERNAL(idtentry->namlen);
+ break;
+
+ default:
+ break;
+ }
+
+ ++nxt; /* advance to next entry to move in sp */
+ }
+
+ left += n;
+ if (left >= half)
+ break;
+ }
+
+ /* <nxt> poins to the 1st entry to move */
+
+ /*
+ * move entries to right page
+ *
+ * dtMoveEntry() initializes rp and reserves entry for insertion
+ *
+ * split page moved out entries are linelocked;
+ * new/right page moved in entries are linelocked;
+ */
+ /* linelock header + stbl of new right page */
+ rlv = & rdtlck->lv[rdtlck->index];
+ rlv->offset = 0;
+ rlv->length = 5;
+ rdtlck->index++;
+
+ dtMoveEntry(sp, nxt, rp, &sdtlck, &rdtlck, DO_INDEX(ip));
+
+ sp->header.nextindex = nxt;
+
+ /*
+ * finalize freelist of new right page
+ */
+ fsi = rp->header.freelist;
+ f = &rp->slot[fsi];
+ for (fsi++; fsi < rp->header.maxslot; f++, fsi++)
+ f->next = fsi;
+ f->next = -1;
+
+ /*
+ * Update directory index table for entries now in right page
+ */
+ if ((rp->header.flag & BT_LEAF) && DO_INDEX(ip)) {
+ mp = 0;
+ stbl = DT_GETSTBL(rp);
+ for (n = 0; n < rp->header.nextindex; n++) {
+ ldtentry = (struct ldtentry *) & rp->slot[stbl[n]];
+ modify_index(tid, ip, le32_to_cpu(ldtentry->index),
+ rbn, n, &mp);
+ }
+ if (mp)
+ release_metapage(mp);
+ }
+
+ /*
+ * the skipped index was on the left page,
+ */
+ if (skip <= off) {
+ /* insert the new entry in the split page */
+ dtInsertEntry(sp, skip, split->key, split->data, &sdtlck);
+
+ /* linelock stbl of split page */
+ if (sdtlck->index >= sdtlck->maxcnt)
+ sdtlck = (struct dt_lock *) txLinelock(sdtlck);
+ slv = & sdtlck->lv[sdtlck->index];
+ n = skip >> L2DTSLOTSIZE;
+ slv->offset = sp->header.stblindex + n;
+ slv->length =
+ ((sp->header.nextindex - 1) >> L2DTSLOTSIZE) - n + 1;
+ sdtlck->index++;
+ }
+ /*
+ * the skipped index was on the right page,
+ */
+ else {
+ /* adjust the skip index to reflect the new position */
+ skip -= nxt;
+
+ /* insert the new entry in the right page */
+ dtInsertEntry(rp, skip, split->key, split->data, &rdtlck);
+ }
+
+ out:
+ *rmpp = rmp;
+ *rpxdp = *pxd;
+
+ ip->i_blocks += LBLK2PBLK(sb, lengthPXD(pxd));
+
+ jEVENT(0, ("dtSplitPage: ip:0x%p sp:0x%p rp:0x%p\n", ip, sp, rp));
+ return 0;
+}
+
+
+/*
+ * dtExtendPage()
+ *
+ * function: extend 1st/only directory leaf page
+ *
+ * parameter:
+ *
+ * return: 0 - success;
+ * errno - failure;
+ * return extended page pinned;
+ */
+static int dtExtendPage(tid_t tid,
+ struct inode *ip, struct dtsplit * split, struct btstack * btstack)
+{
+ struct super_block *sb = ip->i_sb;
+ int rc;
+ struct metapage *smp, *pmp, *mp;
+ dtpage_t *sp, *pp;
+ struct pxdlist *pxdlist;
+ pxd_t *pxd, *tpxd;
+ int xlen, xsize;
+ int newstblindex, newstblsize;
+ int oldstblindex, oldstblsize;
+ int fsi, last;
+ struct dtslot *f;
+ struct btframe *parent;
+ int n;
+ struct dt_lock *dtlck;
+ s64 xaddr, txaddr;
+ struct tlock *tlck;
+ struct pxd_lock *pxdlock;
+ struct lv *lv;
+ uint type;
+ struct ldtentry *ldtentry;
+ u8 *stbl;
+
+ /* get page to extend */
+ smp = split->mp;
+ sp = DT_PAGE(ip, smp);
+
+ /* get parent/root page */
+ parent = BT_POP(btstack);
+ DT_GETPAGE(ip, parent->bn, pmp, PSIZE, pp, rc);
+ if (rc)
+ return (rc);
+
+ /*
+ * extend the extent
+ */
+ pxdlist = split->pxdlist;
+ pxd = &pxdlist->pxd[pxdlist->npxd];
+ pxdlist->npxd++;
+
+ xaddr = addressPXD(pxd);
+ tpxd = &sp->header.self;
+ txaddr = addressPXD(tpxd);
+ /* in-place extension */
+ if (xaddr == txaddr) {
+ type = tlckEXTEND;
+ }
+ /* relocation */
+ else {
+ type = tlckNEW;
+
+ /* save moved extent descriptor for later free */
+ tlck = txMaplock(tid, ip, tlckDTREE | tlckRELOCATE);
+ pxdlock = (struct pxd_lock *) & tlck->lock;
+ pxdlock->flag = mlckFREEPXD;
+ pxdlock->pxd = sp->header.self;
+ pxdlock->index = 1;
+
+ /*
+ * Update directory index table to reflect new page address
+ */
+ if (DO_INDEX(ip)) {
+ mp = 0;
+ stbl = DT_GETSTBL(sp);
+ for (n = 0; n < sp->header.nextindex; n++) {
+ ldtentry =
+ (struct ldtentry *) & sp->slot[stbl[n]];
+ modify_index(tid, ip,
+ le32_to_cpu(ldtentry->index),
+ xaddr, n, &mp);
+ }
+ if (mp)
+ release_metapage(mp);
+ }
+ }
+
+ /*
+ * extend the page
+ */
+ sp->header.self = *pxd;
+
+ jEVENT(0,
+ ("dtExtendPage: ip:0x%p smp:0x%p sp:0x%p\n", ip, smp, sp));
+
+ BT_MARK_DIRTY(smp, ip);
+ /*
+ * acquire a transaction lock on the extended/leaf page
+ */
+ tlck = txLock(tid, ip, smp, tlckDTREE | type);
+ dtlck = (struct dt_lock *) & tlck->lock;
+ lv = & dtlck->lv[0];
+
+ /* update buffer extent descriptor of extended page */
+ xlen = lengthPXD(pxd);
+ xsize = xlen << JFS_SBI(sb)->l2bsize;
+#ifdef _STILL_TO_PORT
+ bmSetXD(smp, xaddr, xsize);
+#endif /* _STILL_TO_PORT */
+
+ /*
+ * copy old stbl to new stbl at start of extended area
+ */
+ oldstblindex = sp->header.stblindex;
+ oldstblsize = (sp->header.maxslot + 31) >> L2DTSLOTSIZE;
+ newstblindex = sp->header.maxslot;
+ n = xsize >> L2DTSLOTSIZE;
+ newstblsize = (n + 31) >> L2DTSLOTSIZE;
+ memcpy(&sp->slot[newstblindex], &sp->slot[oldstblindex],
+ sp->header.nextindex);
+
+ /*
+ * in-line extension: linelock old area of extended page
+ */
+ if (type == tlckEXTEND) {
+ /* linelock header */
+ lv->offset = 0;
+ lv->length = 1;
+ dtlck->index++;
+ lv++;
+
+ /* linelock new stbl of extended page */
+ lv->offset = newstblindex;
+ lv->length = newstblsize;
+ }
+ /*
+ * relocation: linelock whole relocated area
+ */
+ else {
+ lv->offset = 0;
+ lv->length = sp->header.maxslot + newstblsize;
+ }
+
+ dtlck->index++;
+
+ sp->header.maxslot = n;
+ sp->header.stblindex = newstblindex;
+ /* sp->header.nextindex remains the same */
+
+ /*
+ * add old stbl region at head of freelist
+ */
+ fsi = oldstblindex;
+ f = &sp->slot[fsi];
+ last = sp->header.freelist;
+ for (n = 0; n < oldstblsize; n++, fsi++, f++) {
+ f->next = last;
+ last = fsi;
+ }
+ sp->header.freelist = last;
+ sp->header.freecnt += oldstblsize;
+
+ /*
+ * append free region of newly extended area at tail of freelist
+ */
+ /* init free region of newly extended area */
+ fsi = n = newstblindex + newstblsize;
+ f = &sp->slot[fsi];
+ for (fsi++; fsi < sp->header.maxslot; f++, fsi++)
+ f->next = fsi;
+ f->next = -1;
+
+ /* append new free region at tail of old freelist */
+ fsi = sp->header.freelist;
+ if (fsi == -1)
+ sp->header.freelist = n;
+ else {
+ do {
+ f = &sp->slot[fsi];
+ fsi = f->next;
+ } while (fsi != -1);
+
+ f->next = n;
+ }
+
+ sp->header.freecnt += sp->header.maxslot - n;
+
+ /*
+ * insert the new entry
+ */
+ dtInsertEntry(sp, split->index, split->key, split->data, &dtlck);
+
+ BT_MARK_DIRTY(pmp, ip);
+ /*
+ * linelock any freeslots residing in old extent
+ */
+ if (type == tlckEXTEND) {
+ n = sp->header.maxslot >> 2;
+ if (sp->header.freelist < n)
+ dtLinelockFreelist(sp, n, &dtlck);
+ }
+
+ /*
+ * update parent entry on the parent/root page
+ */
+ /*
+ * acquire a transaction lock on the parent/root page
+ */
+ tlck = txLock(tid, ip, pmp, tlckDTREE | tlckENTRY);
+ dtlck = (struct dt_lock *) & tlck->lock;
+ lv = & dtlck->lv[dtlck->index];
+
+ /* linelock parent entry - 1st slot */
+ lv->offset = 1;
+ lv->length = 1;
+ dtlck->index++;
+
+ /* update the parent pxd for page extension */
+ tpxd = (pxd_t *) & pp->slot[1];
+ *tpxd = *pxd;
+
+ /* Since the directory might have an EA and/or ACL associated with it
+ * we need to make sure we take that into account when setting the
+ * i_nblocks
+ */
+ ip->i_blocks = LBLK2PBLK(ip->i_sb, xlen +
+ ((JFS_IP(ip)->ea.flag & DXD_EXTENT) ?
+ lengthDXD(&JFS_IP(ip)->ea) : 0) +
+ ((JFS_IP(ip)->acl.flag & DXD_EXTENT) ?
+ lengthDXD(&JFS_IP(ip)->acl) : 0));
+
+ jEVENT(0,
+ ("dtExtendPage: ip:0x%p smp:0x%p sp:0x%p\n", ip, smp, sp));
+
+
+ DT_PUTPAGE(pmp);
+ return 0;
+}
+
+
+/*
+ * dtSplitRoot()
+ *
+ * function:
+ * split the full root page into
+ * original/root/split page and new right page
+ * i.e., root remains fixed in tree anchor (inode) and
+ * the root is copied to a single new right child page
+ * since root page << non-root page, and
+ * the split root page contains a single entry for the
+ * new right child page.
+ *
+ * parameter:
+ *
+ * return: 0 - success;
+ * errno - failure;
+ * return new page pinned;
+ */
+static int dtSplitRoot(tid_t tid,
+ struct inode *ip, struct dtsplit * split, struct metapage ** rmpp)
+{
+ struct super_block *sb = ip->i_sb;
+ struct metapage *smp;
+ dtroot_t *sp;
+ struct metapage *rmp;
+ dtpage_t *rp;
+ s64 rbn;
+ int xlen;
+ int xsize;
+ struct dtslot *f;
+ s8 *stbl;
+ int fsi, stblsize, n;
+ struct idtentry *s;
+ pxd_t *ppxd;
+ struct pxdlist *pxdlist;
+ pxd_t *pxd;
+ struct dt_lock *dtlck;
+ struct tlock *tlck;
+ struct lv *lv;
+
+ /* get split root page */
+ smp = split->mp;
+ sp = &JFS_IP(ip)->i_dtroot;
+
+ /*
+ * allocate/initialize a single (right) child page
+ *
+ * N.B. at first split, a one (or two) block to fit new entry
+ * is allocated; at subsequent split, a full page is allocated;
+ */
+ pxdlist = split->pxdlist;
+ pxd = &pxdlist->pxd[pxdlist->npxd];
+ pxdlist->npxd++;
+ rbn = addressPXD(pxd);
+ xlen = lengthPXD(pxd);
+ xsize = xlen << JFS_SBI(sb)->l2bsize;
+ rmp = get_metapage(ip, rbn, xsize, 1);
+ rp = rmp->data;
+
+ BT_MARK_DIRTY(rmp, ip);
+ /*
+ * acquire a transaction lock on the new right page
+ */
+ tlck = txLock(tid, ip, rmp, tlckDTREE | tlckNEW);
+ dtlck = (struct dt_lock *) & tlck->lock;
+
+ rp->header.flag =
+ (sp->header.flag & BT_LEAF) ? BT_LEAF : BT_INTERNAL;
+ rp->header.self = *pxd;
+
+ /* initialize sibling pointers */
+ rp->header.next = 0;
+ rp->header.prev = 0;
+
+ /*
+ * move in-line root page into new right page extent
+ */
+ /* linelock header + copied entries + new stbl (1st slot) in new page */
+ ASSERT(dtlck->index == 0);
+ lv = & dtlck->lv[0];
+ lv->offset = 0;
+ lv->length = 10; /* 1 + 8 + 1 */
+ dtlck->index++;
+
+ n = xsize >> L2DTSLOTSIZE;
+ rp->header.maxslot = n;
+ stblsize = (n + 31) >> L2DTSLOTSIZE;
+
+ /* copy old stbl to new stbl at start of extended area */
+ rp->header.stblindex = DTROOTMAXSLOT;
+ stbl = (s8 *) & rp->slot[DTROOTMAXSLOT];
+ memcpy(stbl, sp->header.stbl, sp->header.nextindex);
+ rp->header.nextindex = sp->header.nextindex;
+
+ /* copy old data area to start of new data area */
+ memcpy(&rp->slot[1], &sp->slot[1], IDATASIZE);
+
+ /*
+ * append free region of newly extended area at tail of freelist
+ */
+ /* init free region of newly extended area */
+ fsi = n = DTROOTMAXSLOT + stblsize;
+ f = &rp->slot[fsi];
+ for (fsi++; fsi < rp->header.maxslot; f++, fsi++)
+ f->next = fsi;
+ f->next = -1;
+
+ /* append new free region at tail of old freelist */
+ fsi = sp->header.freelist;
+ if (fsi == -1)
+ rp->header.freelist = n;
+ else {
+ rp->header.freelist = fsi;
+
+ do {
+ f = &rp->slot[fsi];
+ fsi = f->next;
+ } while (fsi != -1);
+
+ f->next = n;
+ }
+
+ rp->header.freecnt = sp->header.freecnt + rp->header.maxslot - n;
+
+ /*
+ * Update directory index table for entries now in right page
+ */
+ if ((rp->header.flag & BT_LEAF) && DO_INDEX(ip)) {
+ struct metapage *mp = 0;
+ struct ldtentry *ldtentry;
+
+ stbl = DT_GETSTBL(rp);
+ for (n = 0; n < rp->header.nextindex; n++) {
+ ldtentry = (struct ldtentry *) & rp->slot[stbl[n]];
+ modify_index(tid, ip, le32_to_cpu(ldtentry->index),
+ rbn, n, &mp);
+ }
+ if (mp)
+ release_metapage(mp);
+ }
+ /*
+ * insert the new entry into the new right/child page
+ * (skip index in the new right page will not change)
+ */
+ dtInsertEntry(rp, split->index, split->key, split->data, &dtlck);
+
+ /*
+ * reset parent/root page
+ *
+ * set the 1st entry offset to 0, which force the left-most key
+ * at any level of the tree to be less than any search key.
+ *
+ * The btree comparison code guarantees that the left-most key on any
+ * level of the tree is never used, so it doesn't need to be filled in.
+ */
+ BT_MARK_DIRTY(smp, ip);
+ /*
+ * acquire a transaction lock on the root page (in-memory inode)
+ */
+ tlck = txLock(tid, ip, smp, tlckDTREE | tlckNEW | tlckBTROOT);
+ dtlck = (struct dt_lock *) & tlck->lock;
+
+ /* linelock root */
+ ASSERT(dtlck->index == 0);
+ lv = & dtlck->lv[0];
+ lv->offset = 0;
+ lv->length = DTROOTMAXSLOT;
+ dtlck->index++;
+
+ /* update page header of root */
+ if (sp->header.flag & BT_LEAF) {
+ sp->header.flag &= ~BT_LEAF;
+ sp->header.flag |= BT_INTERNAL;
+ }
+
+ /* init the first entry */
+ s = (struct idtentry *) & sp->slot[DTENTRYSTART];
+ ppxd = (pxd_t *) s;
+ *ppxd = *pxd;
+ s->next = -1;
+ s->namlen = 0;
+
+ stbl = sp->header.stbl;
+ stbl[0] = DTENTRYSTART;
+ sp->header.nextindex = 1;
+
+ /* init freelist */
+ fsi = DTENTRYSTART + 1;
+ f = &sp->slot[fsi];
+
+ /* init free region of remaining area */
+ for (fsi++; fsi < DTROOTMAXSLOT; f++, fsi++)
+ f->next = fsi;
+ f->next = -1;
+
+ sp->header.freelist = DTENTRYSTART + 1;
+ sp->header.freecnt = DTROOTMAXSLOT - (DTENTRYSTART + 1);
+
+ *rmpp = rmp;
+
+ ip->i_blocks += LBLK2PBLK(ip->i_sb, lengthPXD(pxd));
+ return 0;
+}
+
+
+/*
+ * dtDelete()
+ *
+ * function: delete the entry(s) referenced by a key.
+ *
+ * parameter:
+ *
+ * return:
+ */
+int dtDelete(tid_t tid,
+ struct inode *ip, struct component_name * key, ino_t * ino, int flag)
+{
+ int rc = 0;
+ s64 bn;
+ struct metapage *mp, *imp;
+ dtpage_t *p;
+ int index;
+ struct btstack btstack;
+ struct dt_lock *dtlck;
+ struct tlock *tlck;
+ struct lv *lv;
+ int i;
+ struct ldtentry *ldtentry;
+ u8 *stbl;
+ u32 table_index, next_index;
+ struct metapage *nmp;
+ dtpage_t *np;
+
+ /*
+ * search for the entry to delete:
+ *
+ * dtSearch() returns (leaf page pinned, index at which to delete).
+ */
+ if ((rc = dtSearch(ip, key, ino, &btstack, flag)))
+ return rc;
+
+ /* retrieve search result */
+ DT_GETSEARCH(ip, btstack.top, bn, mp, p, index);
+
+ /*
+ * We need to find put the index of the next entry into the
+ * directory index table in order to resume a readdir from this
+ * entry.
+ */
+ if (DO_INDEX(ip)) {
+ stbl = DT_GETSTBL(p);
+ ldtentry = (struct ldtentry *) & p->slot[stbl[index]];
+ table_index = le32_to_cpu(ldtentry->index);
+ if (index == (p->header.nextindex - 1)) {
+ /*
+ * Last entry in this leaf page
+ */
+ if ((p->header.flag & BT_ROOT)
+ || (p->header.next == 0))
+ next_index = -1;
+ else {
+ /* Read next leaf page */
+ DT_GETPAGE(ip, le64_to_cpu(p->header.next),
+ nmp, PSIZE, np, rc);
+ if (rc)
+ next_index = -1;
+ else {
+ stbl = DT_GETSTBL(np);
+ ldtentry =
+ (struct ldtentry *) & np->
+ slot[stbl[0]];
+ next_index =
+ le32_to_cpu(ldtentry->index);
+ DT_PUTPAGE(nmp);
+ }
+ }
+ } else {
+ ldtentry =
+ (struct ldtentry *) & p->slot[stbl[index + 1]];
+ next_index = le32_to_cpu(ldtentry->index);
+ }
+ free_index(tid, ip, table_index, next_index);
+ }
+ /*
+ * the leaf page becomes empty, delete the page
+ */
+ if (p->header.nextindex == 1) {
+ /* delete empty page */
+ rc = dtDeleteUp(tid, ip, mp, p, &btstack);
+ }
+ /*
+ * the leaf page has other entries remaining:
+ *
+ * delete the entry from the leaf page.
+ */
+ else {
+ BT_MARK_DIRTY(mp, ip);
+ /*
+ * acquire a transaction lock on the leaf page
+ */
+ tlck = txLock(tid, ip, mp, tlckDTREE | tlckENTRY);
+ dtlck = (struct dt_lock *) & tlck->lock;
+
+ /*
+ * Do not assume that dtlck->index will be zero. During a
+ * rename within a directory, this transaction may have
+ * modified this page already when adding the new entry.
+ */
+
+ /* linelock header */
+ if (dtlck->index >= dtlck->maxcnt)
+ dtlck = (struct dt_lock *) txLinelock(dtlck);
+ lv = & dtlck->lv[dtlck->index];
+ lv->offset = 0;
+ lv->length = 1;
+ dtlck->index++;
+
+ /* linelock stbl of non-root leaf page */
+ if (!(p->header.flag & BT_ROOT)) {
+ if (dtlck->index >= dtlck->maxcnt)
+ dtlck = (struct dt_lock *) txLinelock(dtlck);
+ lv = & dtlck->lv[dtlck->index];
+ i = index >> L2DTSLOTSIZE;
+ lv->offset = p->header.stblindex + i;
+ lv->length =
+ ((p->header.nextindex - 1) >> L2DTSLOTSIZE) -
+ i + 1;
+ dtlck->index++;
+ }
+
+ /* free the leaf entry */
+ dtDeleteEntry(p, index, &dtlck);
+
+ /*
+ * Update directory index table for entries moved in stbl
+ */
+ if (DO_INDEX(ip) && index < p->header.nextindex) {
+ imp = 0;
+ stbl = DT_GETSTBL(p);
+ for (i = index; i < p->header.nextindex; i++) {
+ ldtentry =
+ (struct ldtentry *) & p->slot[stbl[i]];
+ modify_index(tid, ip,
+ le32_to_cpu(ldtentry->index),
+ bn, i, &imp);
+ }
+ if (imp)
+ release_metapage(imp);
+ }
+
+ DT_PUTPAGE(mp);
+ }
+
+ return rc;
+}
+
+
+/*
+ * dtDeleteUp()
+ *
+ * function:
+ * free empty pages as propagating deletion up the tree
+ *
+ * parameter:
+ *
+ * return:
+ */
+static int dtDeleteUp(tid_t tid, struct inode *ip,
+ struct metapage * fmp, dtpage_t * fp, struct btstack * btstack)
+{
+ int rc = 0;
+ struct metapage *mp;
+ dtpage_t *p;
+ int index, nextindex;
+ int xlen;
+ struct btframe *parent;
+ struct dt_lock *dtlck;
+ struct tlock *tlck;
+ struct lv *lv;
+ struct pxd_lock *pxdlock;
+ int i;
+
+ /*
+ * keep the root leaf page which has become empty
+ */
+ if (BT_IS_ROOT(fmp)) {
+ /*
+ * reset the root
+ *
+ * dtInitRoot() acquires txlock on the root
+ */
+ dtInitRoot(tid, ip, PARENT(ip));
+
+ DT_PUTPAGE(fmp);
+
+ return 0;
+ }
+
+ /*
+ * free the non-root leaf page
+ */
+ /*
+ * acquire a transaction lock on the page
+ *
+ * write FREEXTENT|NOREDOPAGE log record
+ * N.B. linelock is overlaid as freed extent descriptor, and
+ * the buffer page is freed;
+ */
+ tlck = txMaplock(tid, ip, tlckDTREE | tlckFREE);
+ pxdlock = (struct pxd_lock *) & tlck->lock;
+ pxdlock->flag = mlckFREEPXD;
+ pxdlock->pxd = fp->header.self;
+ pxdlock->index = 1;
+
+ /* update sibling pointers */
+ if ((rc = dtRelink(tid, ip, fp)))
+ return rc;
+
+ xlen = lengthPXD(&fp->header.self);
+ ip->i_blocks -= LBLK2PBLK(ip->i_sb, xlen);
+
+ /* free/invalidate its buffer page */
+ discard_metapage(fmp);
+
+ /*
+ * propagate page deletion up the directory tree
+ *
+ * If the delete from the parent page makes it empty,
+ * continue all the way up the tree.
+ * stop if the root page is reached (which is never deleted) or
+ * if the entry deletion does not empty the page.
+ */
+ while ((parent = BT_POP(btstack)) != NULL) {
+ /* pin the parent page <sp> */
+ DT_GETPAGE(ip, parent->bn, mp, PSIZE, p, rc);
+ if (rc)
+ return rc;
+
+ /*
+ * free the extent of the child page deleted
+ */
+ index = parent->index;
+
+ /*
+ * delete the entry for the child page from parent
+ */
+ nextindex = p->header.nextindex;
+
+ /*
+ * the parent has the single entry being deleted:
+ *
+ * free the parent page which has become empty.
+ */
+ if (nextindex == 1) {
+ /*
+ * keep the root internal page which has become empty
+ */
+ if (p->header.flag & BT_ROOT) {
+ /*
+ * reset the root
+ *
+ * dtInitRoot() acquires txlock on the root
+ */
+ dtInitRoot(tid, ip, PARENT(ip));
+
+ DT_PUTPAGE(mp);
+
+ return 0;
+ }
+ /*
+ * free the parent page
+ */
+ else {
+ /*
+ * acquire a transaction lock on the page
+ *
+ * write FREEXTENT|NOREDOPAGE log record
+ */
+ tlck =
+ txMaplock(tid, ip,
+ tlckDTREE | tlckFREE);
+ pxdlock = (struct pxd_lock *) & tlck->lock;
+ pxdlock->flag = mlckFREEPXD;
+ pxdlock->pxd = p->header.self;
+ pxdlock->index = 1;
+
+ /* update sibling pointers */
+ if ((rc = dtRelink(tid, ip, p)))
+ return rc;
+
+ xlen = lengthPXD(&p->header.self);
+ ip->i_blocks -= LBLK2PBLK(ip->i_sb, xlen);
+
+ /* free/invalidate its buffer page */
+ discard_metapage(mp);
+
+ /* propagate up */
+ continue;
+ }
+ }
+
+ /*
+ * the parent has other entries remaining:
+ *
+ * delete the router entry from the parent page.
+ */
+ BT_MARK_DIRTY(mp, ip);
+ /*
+ * acquire a transaction lock on the page
+ *
+ * action: router entry deletion
+ */
+ tlck = txLock(tid, ip, mp, tlckDTREE | tlckENTRY);
+ dtlck = (struct dt_lock *) & tlck->lock;
+
+ /* linelock header */
+ if (dtlck->index >= dtlck->maxcnt)
+ dtlck = (struct dt_lock *) txLinelock(dtlck);
+ lv = & dtlck->lv[dtlck->index];
+ lv->offset = 0;
+ lv->length = 1;
+ dtlck->index++;
+
+ /* linelock stbl of non-root leaf page */
+ if (!(p->header.flag & BT_ROOT)) {
+ if (dtlck->index < dtlck->maxcnt)
+ lv++;
+ else {
+ dtlck = (struct dt_lock *) txLinelock(dtlck);
+ lv = & dtlck->lv[0];
+ }
+ i = index >> L2DTSLOTSIZE;
+ lv->offset = p->header.stblindex + i;
+ lv->length =
+ ((p->header.nextindex - 1) >> L2DTSLOTSIZE) -
+ i + 1;
+ dtlck->index++;
+ }
+
+ /* free the router entry */
+ dtDeleteEntry(p, index, &dtlck);
+
+ /* reset key of new leftmost entry of level (for consistency) */
+ if (index == 0 &&
+ ((p->header.flag & BT_ROOT) || p->header.prev == 0))
+ dtTruncateEntry(p, 0, &dtlck);
+
+ /* unpin the parent page */
+ DT_PUTPAGE(mp);
+
+ /* exit propagation up */
+ break;
+ }
+
+ return 0;
+}
+
+
+/*
+ * NAME: dtRelocate()
+ *
+ * FUNCTION: relocate dtpage (internal or leaf) of directory;
+ * This function is mainly used by defragfs utility.
+ */
+int dtRelocate(tid_t tid, struct inode *ip, s64 lmxaddr, pxd_t * opxd,
+ s64 nxaddr)
+{
+ int rc = 0;
+ struct metapage *mp, *pmp, *lmp, *rmp;
+ dtpage_t *p, *pp, *rp = 0, *lp= 0;
+ s64 bn;
+ int index;
+ struct btstack btstack;
+ pxd_t *pxd;
+ s64 oxaddr, nextbn, prevbn;
+ int xlen, xsize;
+ struct tlock *tlck;
+ struct dt_lock *dtlck;
+ struct pxd_lock *pxdlock;
+ s8 *stbl;
+ struct lv *lv;
+
+ oxaddr = addressPXD(opxd);
+ xlen = lengthPXD(opxd);
+
+ jEVENT(0, ("dtRelocate: lmxaddr:%Ld xaddr:%Ld:%Ld xlen:%d\n",
+ (long long)lmxaddr, (long long)oxaddr, (long long)nxaddr,
+ xlen));
+
+ /*
+ * 1. get the internal parent dtpage covering
+ * router entry for the tartget page to be relocated;
+ */
+ rc = dtSearchNode(ip, lmxaddr, opxd, &btstack);
+ if (rc)
+ return rc;
+
+ /* retrieve search result */
+ DT_GETSEARCH(ip, btstack.top, bn, pmp, pp, index);
+ jEVENT(0, ("dtRelocate: parent router entry validated.\n"));
+
+ /*
+ * 2. relocate the target dtpage
+ */
+ /* read in the target page from src extent */
+ DT_GETPAGE(ip, oxaddr, mp, PSIZE, p, rc);
+ if (rc) {
+ /* release the pinned parent page */
+ DT_PUTPAGE(pmp);
+ return rc;
+ }
+
+ /*
+ * read in sibling pages if any to update sibling pointers;
+ */
+ rmp = NULL;
+ if (p->header.next) {
+ nextbn = le64_to_cpu(p->header.next);
+ DT_GETPAGE(ip, nextbn, rmp, PSIZE, rp, rc);
+ if (rc) {
+ DT_PUTPAGE(mp);
+ DT_PUTPAGE(pmp);
+ return (rc);
+ }
+ }
+
+ lmp = NULL;
+ if (p->header.prev) {
+ prevbn = le64_to_cpu(p->header.prev);
+ DT_GETPAGE(ip, prevbn, lmp, PSIZE, lp, rc);
+ if (rc) {
+ DT_PUTPAGE(mp);
+ DT_PUTPAGE(pmp);
+ if (rmp)
+ DT_PUTPAGE(rmp);
+ return (rc);
+ }
+ }
+
+ /* at this point, all xtpages to be updated are in memory */
+
+ /*
+ * update sibling pointers of sibling dtpages if any;
+ */
+ if (lmp) {
+ tlck = txLock(tid, ip, lmp, tlckDTREE | tlckRELINK);
+ dtlck = (struct dt_lock *) & tlck->lock;
+ /* linelock header */
+ ASSERT(dtlck->index == 0);
+ lv = & dtlck->lv[0];
+ lv->offset = 0;
+ lv->length = 1;
+ dtlck->index++;
+
+ lp->header.next = cpu_to_le64(nxaddr);
+ DT_PUTPAGE(lmp);
+ }
+
+ if (rmp) {
+ tlck = txLock(tid, ip, rmp, tlckDTREE | tlckRELINK);
+ dtlck = (struct dt_lock *) & tlck->lock;
+ /* linelock header */
+ ASSERT(dtlck->index == 0);
+ lv = & dtlck->lv[0];
+ lv->offset = 0;
+ lv->length = 1;
+ dtlck->index++;
+
+ rp->header.prev = cpu_to_le64(nxaddr);
+ DT_PUTPAGE(rmp);
+ }
+
+ /*
+ * update the target dtpage to be relocated
+ *
+ * write LOG_REDOPAGE of LOG_NEW type for dst page
+ * for the whole target page (logredo() will apply
+ * after image and update bmap for allocation of the
+ * dst extent), and update bmap for allocation of
+ * the dst extent;
+ */
+ tlck = txLock(tid, ip, mp, tlckDTREE | tlckNEW);
+ dtlck = (struct dt_lock *) & tlck->lock;
+ /* linelock header */
+ ASSERT(dtlck->index == 0);
+ lv = & dtlck->lv[0];
+
+ /* update the self address in the dtpage header */
+ pxd = &p->header.self;
+ PXDaddress(pxd, nxaddr);
+
+ /* the dst page is the same as the src page, i.e.,
+ * linelock for afterimage of the whole page;
+ */
+ lv->offset = 0;
+ lv->length = p->header.maxslot;
+ dtlck->index++;
+
+ /* update the buffer extent descriptor of the dtpage */
+ xsize = xlen << JFS_SBI(ip->i_sb)->l2bsize;
+#ifdef _STILL_TO_PORT
+ bmSetXD(mp, nxaddr, xsize);
+#endif /* _STILL_TO_PORT */
+ /* unpin the relocated page */
+ DT_PUTPAGE(mp);
+ jEVENT(0, ("dtRelocate: target dtpage relocated.\n"));
+
+ /* the moved extent is dtpage, then a LOG_NOREDOPAGE log rec
+ * needs to be written (in logredo(), the LOG_NOREDOPAGE log rec
+ * will also force a bmap update ).
+ */
+
+ /*
+ * 3. acquire maplock for the source extent to be freed;
+ */
+ /* for dtpage relocation, write a LOG_NOREDOPAGE record
+ * for the source dtpage (logredo() will init NoRedoPage
+ * filter and will also update bmap for free of the source
+ * dtpage), and upadte bmap for free of the source dtpage;
+ */
+ tlck = txMaplock(tid, ip, tlckDTREE | tlckFREE);
+ pxdlock = (struct pxd_lock *) & tlck->lock;
+ pxdlock->flag = mlckFREEPXD;
+ PXDaddress(&pxdlock->pxd, oxaddr);
+ PXDlength(&pxdlock->pxd, xlen);
+ pxdlock->index = 1;
+
+ /*
+ * 4. update the parent router entry for relocation;
+ *
+ * acquire tlck for the parent entry covering the target dtpage;
+ * write LOG_REDOPAGE to apply after image only;
+ */
+ jEVENT(0, ("dtRelocate: update parent router entry.\n"));
+ tlck = txLock(tid, ip, pmp, tlckDTREE | tlckENTRY);
+ dtlck = (struct dt_lock *) & tlck->lock;
+ lv = & dtlck->lv[dtlck->index];
+
+ /* update the PXD with the new address */
+ stbl = DT_GETSTBL(pp);
+ pxd = (pxd_t *) & pp->slot[stbl[index]];
+ PXDaddress(pxd, nxaddr);
+ lv->offset = stbl[index];
+ lv->length = 1;
+ dtlck->index++;
+
+ /* unpin the parent dtpage */
+ DT_PUTPAGE(pmp);
+
+ return rc;
+}
+
+
+/*
+ * NAME: dtSearchNode()
+ *
+ * FUNCTION: Search for an dtpage containing a specified address
+ * This function is mainly used by defragfs utility.
+ *
+ * NOTE: Search result on stack, the found page is pinned at exit.
+ * The result page must be an internal dtpage.
+ * lmxaddr give the address of the left most page of the
+ * dtree level, in which the required dtpage resides.
+ */
+static int dtSearchNode(struct inode *ip, s64 lmxaddr, pxd_t * kpxd,
+ struct btstack * btstack)
+{
+ int rc = 0;
+ s64 bn;
+ struct metapage *mp;
+ dtpage_t *p;
+ int psize = 288; /* initial in-line directory */
+ s8 *stbl;
+ int i;
+ pxd_t *pxd;
+ struct btframe *btsp;
+
+ BT_CLR(btstack); /* reset stack */
+
+ /*
+ * descend tree to the level with specified leftmost page
+ *
+ * by convention, root bn = 0.
+ */
+ for (bn = 0;;) {
+ /* get/pin the page to search */
+ DT_GETPAGE(ip, bn, mp, psize, p, rc);
+ if (rc)
+ return rc;
+
+ /* does the xaddr of leftmost page of the levevl
+ * matches levevl search key ?
+ */
+ if (p->header.flag & BT_ROOT) {
+ if (lmxaddr == 0)
+ break;
+ } else if (addressPXD(&p->header.self) == lmxaddr)
+ break;
+
+ /*
+ * descend down to leftmost child page
+ */
+ if (p->header.flag & BT_LEAF)
+ return ESTALE;
+
+ /* get the leftmost entry */
+ stbl = DT_GETSTBL(p);
+ pxd = (pxd_t *) & p->slot[stbl[0]];
+
+ /* get the child page block address */
+ bn = addressPXD(pxd);
+ psize = lengthPXD(pxd) << JFS_SBI(ip->i_sb)->l2bsize;
+ /* unpin the parent page */
+ DT_PUTPAGE(mp);
+ }
+
+ /*
+ * search each page at the current levevl
+ */
+ loop:
+ stbl = DT_GETSTBL(p);
+ for (i = 0; i < p->header.nextindex; i++) {
+ pxd = (pxd_t *) & p->slot[stbl[i]];
+
+ /* found the specified router entry */
+ if (addressPXD(pxd) == addressPXD(kpxd) &&
+ lengthPXD(pxd) == lengthPXD(kpxd)) {
+ btsp = btstack->top;
+ btsp->bn = bn;
+ btsp->index = i;
+ btsp->mp = mp;
+
+ return 0;
+ }
+ }
+
+ /* get the right sibling page if any */
+ if (p->header.next)
+ bn = le64_to_cpu(p->header.next);
+ else {
+ DT_PUTPAGE(mp);
+ return ESTALE;
+ }
+
+ /* unpin current page */
+ DT_PUTPAGE(mp);
+
+ /* get the right sibling page */
+ DT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+ if (rc)
+ return rc;
+
+ goto loop;
+}
+
+
+/*
+ * dtRelink()
+ *
+ * function:
+ * link around a freed page.
+ *
+ * parameter:
+ * fp: page to be freed
+ *
+ * return:
+ */
+static int dtRelink(tid_t tid, struct inode *ip, dtpage_t * p)
+{
+ int rc;
+ struct metapage *mp;
+ s64 nextbn, prevbn;
+ struct tlock *tlck;
+ struct dt_lock *dtlck;
+ struct lv *lv;
+
+ nextbn = le64_to_cpu(p->header.next);
+ prevbn = le64_to_cpu(p->header.prev);
+
+ /* update prev pointer of the next page */
+ if (nextbn != 0) {
+ DT_GETPAGE(ip, nextbn, mp, PSIZE, p, rc);
+ if (rc)
+ return rc;
+
+ BT_MARK_DIRTY(mp, ip);
+ /*
+ * acquire a transaction lock on the next page
+ *
+ * action: update prev pointer;
+ */
+ tlck = txLock(tid, ip, mp, tlckDTREE | tlckRELINK);
+ jEVENT(0,
+ ("dtRelink nextbn: tlck = 0x%p, ip = 0x%p, mp=0x%p\n",
+ tlck, ip, mp));
+ dtlck = (struct dt_lock *) & tlck->lock;
+
+ /* linelock header */
+ if (dtlck->index >= dtlck->maxcnt)
+ dtlck = (struct dt_lock *) txLinelock(dtlck);
+ lv = & dtlck->lv[dtlck->index];
+ lv->offset = 0;
+ lv->length = 1;
+ dtlck->index++;
+
+ p->header.prev = cpu_to_le64(prevbn);
+ DT_PUTPAGE(mp);
+ }
+
+ /* update next pointer of the previous page */
+ if (prevbn != 0) {
+ DT_GETPAGE(ip, prevbn, mp, PSIZE, p, rc);
+ if (rc)
+ return rc;
+
+ BT_MARK_DIRTY(mp, ip);
+ /*
+ * acquire a transaction lock on the prev page
+ *
+ * action: update next pointer;
+ */
+ tlck = txLock(tid, ip, mp, tlckDTREE | tlckRELINK);
+ jEVENT(0,
+ ("dtRelink prevbn: tlck = 0x%p, ip = 0x%p, mp=0x%p\n",
+ tlck, ip, mp));
+ dtlck = (struct dt_lock *) & tlck->lock;
+
+ /* linelock header */
+ if (dtlck->index >= dtlck->maxcnt)
+ dtlck = (struct dt_lock *) txLinelock(dtlck);
+ lv = & dtlck->lv[dtlck->index];
+ lv->offset = 0;
+ lv->length = 1;
+ dtlck->index++;
+
+ p->header.next = cpu_to_le64(nextbn);
+ DT_PUTPAGE(mp);
+ }
+
+ return 0;
+}
+
+
+/*
+ * dtInitRoot()
+ *
+ * initialize directory root (inline in inode)
+ */
+void dtInitRoot(tid_t tid, struct inode *ip, u32 idotdot)
+{
+ struct jfs_inode_info *jfs_ip = JFS_IP(ip);
+ dtroot_t *p;
+ int fsi;
+ struct dtslot *f;
+ struct tlock *tlck;
+ struct dt_lock *dtlck;
+ struct lv *lv;
+ u16 xflag_save;
+
+ /*
+ * If this was previously an non-empty directory, we need to remove
+ * the old directory table.
+ */
+ if (DO_INDEX(ip)) {
+ if (jfs_ip->next_index > (MAX_INLINE_DIRTABLE_ENTRY + 1)) {
+ struct tblock *tblk = tid_to_tblock(tid);
+ /*
+ * We're playing games with the tid's xflag. If
+ * we're removing a regular file, the file's xtree
+ * is committed with COMMIT_PMAP, but we always
+ * commit the directories xtree with COMMIT_PWMAP.
+ */
+ xflag_save = tblk->xflag;
+ tblk->xflag = 0;
+ /*
+ * xtTruncate isn't guaranteed to fully truncate
+ * the xtree. The caller needs to check i_size
+ * after committing the transaction to see if
+ * additional truncation is needed. The
+ * COMMIT_Stale flag tells caller that we
+ * initiated the truncation.
+ */
+ xtTruncate(tid, ip, 0, COMMIT_PWMAP);
+ set_cflag(COMMIT_Stale, ip);
+
+ tblk->xflag = xflag_save;
+ /*
+ * Tells jfs_metapage code that the metadata pages
+ * for the index table are no longer useful, and
+ * remove them from page cache.
+ */
+ invalidate_inode_metapages(ip);
+ } else
+ ip->i_size = 1;
+
+ jfs_ip->next_index = 2;
+ } else
+ ip->i_size = IDATASIZE;
+
+ /*
+ * acquire a transaction lock on the root
+ *
+ * action: directory initialization;
+ */
+ tlck = txLock(tid, ip, (struct metapage *) & jfs_ip->bxflag,
+ tlckDTREE | tlckENTRY | tlckBTROOT);
+ dtlck = (struct dt_lock *) & tlck->lock;
+
+ /* linelock root */
+ ASSERT(dtlck->index == 0);
+ lv = & dtlck->lv[0];
+ lv->offset = 0;
+ lv->length = DTROOTMAXSLOT;
+ dtlck->index++;
+
+ p = &jfs_ip->i_dtroot;
+
+ p->header.flag = DXD_INDEX | BT_ROOT | BT_LEAF;
+
+ p->header.nextindex = 0;
+
+ /* init freelist */
+ fsi = 1;
+ f = &p->slot[fsi];
+
+ /* init data area of root */
+ for (fsi++; fsi < DTROOTMAXSLOT; f++, fsi++)
+ f->next = fsi;
+ f->next = -1;
+
+ p->header.freelist = 1;
+ p->header.freecnt = 8;
+
+ /* init '..' entry */
+ p->header.idotdot = cpu_to_le32(idotdot);
+
+#if 0
+ ip->i_blocks = LBLK2PBLK(ip->i_sb,
+ ((jfs_ip->ea.flag & DXD_EXTENT) ?
+ lengthDXD(&jfs_ip->ea) : 0) +
+ ((jfs_ip->acl.flag & DXD_EXTENT) ?
+ lengthDXD(&jfs_ip->acl) : 0));
+#endif
+
+ return;
+}
+
+/*
+ * add_missing_indices()
+ *
+ * function: Fix dtree page in which one or more entries has an invalid index.
+ * fsck.jfs should really fix this, but it currently does not.
+ * Called from jfs_readdir when bad index is detected.
+ */
+static void add_missing_indices(struct inode *inode, s64 bn)
+{
+ struct ldtentry *d;
+ struct dt_lock *dtlck;
+ int i;
+ uint index;
+ struct lv *lv;
+ struct metapage *mp;
+ dtpage_t *p;
+ int rc;
+ s8 *stbl;
+ tid_t tid;
+ struct tlock *tlck;
+
+ tid = txBegin(inode->i_sb, 0);
+
+ DT_GETPAGE(inode, bn, mp, PSIZE, p, rc);
+
+ if (rc) {
+ printk(KERN_ERR "DT_GETPAGE failed!\n");
+ goto end;
+ }
+ BT_MARK_DIRTY(mp, inode);
+
+ ASSERT(p->header.flag & BT_LEAF);
+
+ tlck = txLock(tid, inode, mp, tlckDTREE | tlckENTRY);
+ dtlck = (struct dt_lock *) &tlck->lock;
+
+ stbl = DT_GETSTBL(p);
+ for (i = 0; i < p->header.nextindex; i++) {
+ d = (struct ldtentry *) &p->slot[stbl[i]];
+ index = le32_to_cpu(d->index);
+ if ((index < 2) || (index >= JFS_IP(inode)->next_index)) {
+ d->index = cpu_to_le32(add_index(tid, inode, bn, i));
+ if (dtlck->index >= dtlck->maxcnt)
+ dtlck = (struct dt_lock *) txLinelock(dtlck);
+ lv = dtlck->lv;
+ lv->offset = stbl[i];
+ lv->length = 1;
+ dtlck->index++;
+ }
+ }
+
+ DT_PUTPAGE(mp);
+ (void) txCommit(tid, 1, &inode, 0);
+end:
+ txEnd(tid);
+}
+
+/*
+ * Buffer to hold directory entry info while traversing a dtree page
+ * before being fed to the filldir function
+ */
+struct jfs_dirent {
+ loff_t position;
+ int ino;
+ u16 name_len;
+ char name[0];
+};
+
+/*
+ * function to determine next variable-sized jfs_dirent in buffer
+ */
+inline struct jfs_dirent *next_jfs_dirent(struct jfs_dirent *dirent)
+{
+ return (struct jfs_dirent *)
+ ((char *)dirent +
+ ((sizeof (struct jfs_dirent) + dirent->name_len + 1 +
+ sizeof (loff_t) - 1) &
+ ~(sizeof (loff_t) - 1)));
+}
+
+/*
+ * jfs_readdir()
+ *
+ * function: read directory entries sequentially
+ * from the specified entry offset
+ *
+ * parameter:
+ *
+ * return: offset = (pn, index) of start entry
+ * of next jfs_readdir()/dtRead()
+ */
+int jfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
+{
+ struct inode *ip = filp->f_dentry->d_inode;
+ struct nls_table *codepage = JFS_SBI(ip->i_sb)->nls_tab;
+ int rc = 0;
+ loff_t dtpos; /* legacy OS/2 style position */
+ struct dtoffset {
+ s16 pn;
+ s16 index;
+ s32 unused;
+ } *dtoffset = (struct dtoffset *) &dtpos;
+ s64 bn;
+ struct metapage *mp;
+ dtpage_t *p;
+ int index;
+ s8 *stbl;
+ struct btstack btstack;
+ int i, next;
+ struct ldtentry *d;
+ struct dtslot *t;
+ int d_namleft, len, outlen;
+ unsigned long dirent_buf;
+ char *name_ptr;
+ int dtlhdrdatalen;
+ u32 dir_index;
+ int do_index = 0;
+ uint loop_count = 0;
+ struct jfs_dirent *jfs_dirent;
+ int jfs_dirents;
+ int overflow, fix_page, page_fixed = 0;
+ static int unique_pos = 2; /* If we can't fix broken index */
+
+ if (filp->f_pos == DIREND)
+ return 0;
+
+ if (DO_INDEX(ip)) {
+ /*
+ * persistent index is stored in directory entries.
+ * Special cases: 0 = .
+ * 1 = ..
+ * -1 = End of directory
+ */
+ do_index = 1;
+ dtlhdrdatalen = DTLHDRDATALEN;
+
+ dir_index = (u32) filp->f_pos;
+
+ if (dir_index > 1) {
+ struct dir_table_slot dirtab_slot;
+
+ if (dtEmpty(ip) ||
+ (dir_index >= JFS_IP(ip)->next_index)) {
+ /* Stale position. Directory has shrunk */
+ filp->f_pos = DIREND;
+ return 0;
+ }
+ repeat:
+ rc = read_index(ip, dir_index, &dirtab_slot);
+ if (rc) {
+ filp->f_pos = DIREND;
+ return rc;
+ }
+ if (dirtab_slot.flag == DIR_INDEX_FREE) {
+ if (loop_count++ > JFS_IP(ip)->next_index) {
+ jERROR(1, ("jfs_readdir detected "
+ "infinite loop!\n"));
+ filp->f_pos = DIREND;
+ return 0;
+ }
+ dir_index = le32_to_cpu(dirtab_slot.addr2);
+ if (dir_index == -1) {
+ filp->f_pos = DIREND;
+ return 0;
+ }
+ goto repeat;
+ }
+ bn = addressDTS(&dirtab_slot);
+ index = dirtab_slot.slot;
+ DT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+ if (rc) {
+ filp->f_pos = DIREND;
+ return 0;
+ }
+ if (p->header.flag & BT_INTERNAL) {
+ jERROR(1,("jfs_readdir: bad index table\n"));
+ DT_PUTPAGE(mp);
+ filp->f_pos = -1;
+ return 0;
+ }
+ } else {
+ if (dir_index == 0) {
+ /*
+ * self "."
+ */
+ filp->f_pos = 0;
+ if (filldir(dirent, ".", 1, 0, ip->i_ino,
+ DT_DIR))
+ return 0;
+ }
+ /*
+ * parent ".."
+ */
+ filp->f_pos = 1;
+ if (filldir(dirent, "..", 2, 1, PARENT(ip), DT_DIR))
+ return 0;
+
+ /*
+ * Find first entry of left-most leaf
+ */
+ if (dtEmpty(ip)) {
+ filp->f_pos = DIREND;
+ return 0;
+ }
+
+ if ((rc = dtReadFirst(ip, &btstack)))
+ return -rc;
+
+ DT_GETSEARCH(ip, btstack.top, bn, mp, p, index);
+ }
+ } else {
+ /*
+ * Legacy filesystem - OS/2 & Linux JFS < 0.3.6
+ *
+ * pn = index = 0: First entry "."
+ * pn = 0; index = 1: Second entry ".."
+ * pn > 0: Real entries, pn=1 -> leftmost page
+ * pn = index = -1: No more entries
+ */
+ dtlhdrdatalen = DTLHDRDATALEN_LEGACY;
+
+ dtpos = filp->f_pos;
+ if (dtpos == 0) {
+ /* build "." entry */
+
+ if (filldir(dirent, ".", 1, filp->f_pos, ip->i_ino,
+ DT_DIR))
+ return 0;
+ dtoffset->index = 1;
+ filp->f_pos = dtpos;
+ }
+
+ if (dtoffset->pn == 0) {
+ if (dtoffset->index == 1) {
+ /* build ".." entry */
+
+ if (filldir(dirent, "..", 2, filp->f_pos,
+ PARENT(ip), DT_DIR))
+ return 0;
+ } else {
+ jERROR(1,
+ ("jfs_readdir called with invalid offset!\n"));
+ }
+ dtoffset->pn = 1;
+ dtoffset->index = 0;
+ filp->f_pos = dtpos;
+ }
+
+ if (dtEmpty(ip)) {
+ filp->f_pos = DIREND;
+ return 0;
+ }
+
+ if ((rc = dtReadNext(ip, &filp->f_pos, &btstack))) {
+ jERROR(1,
+ ("jfs_readdir: unexpected rc = %d from dtReadNext\n",
+ rc));
+ filp->f_pos = DIREND;
+ return 0;
+ }
+ /* get start leaf page and index */
+ DT_GETSEARCH(ip, btstack.top, bn, mp, p, index);
+
+ /* offset beyond directory eof ? */
+ if (bn < 0) {
+ filp->f_pos = DIREND;
+ return 0;
+ }
+ }
+
+ dirent_buf = __get_free_page(GFP_KERNEL);
+ if (dirent_buf == 0) {
+ DT_PUTPAGE(mp);
+ jERROR(1, ("jfs_readdir: __get_free_page failed!\n"));
+ filp->f_pos = DIREND;
+ return -ENOMEM;
+ }
+
+ while (1) {
+ jfs_dirent = (struct jfs_dirent *) dirent_buf;
+ jfs_dirents = 0;
+ overflow = fix_page = 0;
+
+ stbl = DT_GETSTBL(p);
+
+ for (i = index; i < p->header.nextindex; i++) {
+ d = (struct ldtentry *) & p->slot[stbl[i]];
+
+ if (((long) jfs_dirent + d->namlen + 1) >
+ (dirent_buf + PSIZE)) {
+ /* DBCS codepages could overrun dirent_buf */
+ index = i;
+ overflow = 1;
+ break;
+ }
+
+ d_namleft = d->namlen;
+ name_ptr = jfs_dirent->name;
+ jfs_dirent->ino = le32_to_cpu(d->inumber);
+
+ if (do_index) {
+ len = min(d_namleft, DTLHDRDATALEN);
+ jfs_dirent->position = le32_to_cpu(d->index);
+ /*
+ * d->index should always be valid, but it
+ * isn't. fsck.jfs doesn't create the
+ * directory index for the lost+found
+ * directory. Rather than let it go,
+ * we can try to fix it.
+ */
+ if ((jfs_dirent->position < 2) ||
+ (jfs_dirent->position >=
+ JFS_IP(ip)->next_index)) {
+ if (!page_fixed && !isReadOnly(ip)) {
+ fix_page = 1;
+ /*
+ * setting overflow and setting
+ * index to i will cause the
+ * same page to be processed
+ * again starting here
+ */
+ overflow = 1;
+ index = i;
+ break;
+ }
+ jfs_dirent->position = unique_pos++;
+ }
+ } else {
+ jfs_dirent->position = dtpos;
+ len = min(d_namleft, DTLHDRDATALEN_LEGACY);
+ }
+
+ /* copy the name of head/only segment */
+ outlen = jfs_strfromUCS_le(name_ptr, d->name, len,
+ codepage);
+ jfs_dirent->name_len = outlen;
+
+ /* copy name in the additional segment(s) */
+ next = d->next;
+ while (next >= 0) {
+ t = (struct dtslot *) & p->slot[next];
+ name_ptr += outlen;
+ d_namleft -= len;
+ /* Sanity Check */
+ if (d_namleft == 0) {
+ jERROR(1,("JFS:Dtree error: "
+ "ino = %ld, bn=%Ld, index = %d\n",
+ (long)ip->i_ino, (long long)bn, i));
+ updateSuper(ip->i_sb, FM_DIRTY);
+ goto skip_one;
+ }
+ len = min(d_namleft, DTSLOTDATALEN);
+ outlen = jfs_strfromUCS_le(name_ptr, t->name,
+ len, codepage);
+ jfs_dirent->name_len += outlen;
+
+ next = t->next;
+ }
+
+ jfs_dirents++;
+ jfs_dirent = next_jfs_dirent(jfs_dirent);
+skip_one:
+ if (!do_index)
+ dtoffset->index++;
+ }
+
+ if (!overflow) {
+ /* Point to next leaf page */
+ if (p->header.flag & BT_ROOT)
+ bn = 0;
+ else {
+ bn = le64_to_cpu(p->header.next);
+ index = 0;
+ /* update offset (pn:index) for new page */
+ if (!do_index) {
+ dtoffset->pn++;
+ dtoffset->index = 0;
+ }
+ }
+ page_fixed = 0;
+ }
+
+ /* unpin previous leaf page */
+ DT_PUTPAGE(mp);
+
+ jfs_dirent = (struct jfs_dirent *) dirent_buf;
+ while (jfs_dirents--) {
+ filp->f_pos = jfs_dirent->position;
+ if (filldir(dirent, jfs_dirent->name,
+ jfs_dirent->name_len, filp->f_pos,
+ jfs_dirent->ino, DT_UNKNOWN))
+ goto out;
+ jfs_dirent = next_jfs_dirent(jfs_dirent);
+ }
+
+ if (fix_page) {
+ add_missing_indices(ip, bn);
+ page_fixed = 1;
+ }
+
+ if (!overflow && (bn == 0)) {
+ filp->f_pos = DIREND;
+ break;
+ }
+
+ DT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+ if (rc) {
+ free_page(dirent_buf);
+ return -rc;
+ }
+ }
+
+ out:
+ free_page(dirent_buf);
+
+ return rc;
+}
+
+
+/*
+ * dtReadFirst()
+ *
+ * function: get the leftmost page of the directory
+ */
+static int dtReadFirst(struct inode *ip, struct btstack * btstack)
+{
+ int rc = 0;
+ s64 bn;
+ int psize = 288; /* initial in-line directory */
+ struct metapage *mp;
+ dtpage_t *p;
+ s8 *stbl;
+ struct btframe *btsp;
+ pxd_t *xd;
+
+ BT_CLR(btstack); /* reset stack */
+
+ /*
+ * descend leftmost path of the tree
+ *
+ * by convention, root bn = 0.
+ */
+ for (bn = 0;;) {
+ DT_GETPAGE(ip, bn, mp, psize, p, rc);
+ if (rc)
+ return rc;
+
+ /*
+ * leftmost leaf page
+ */
+ if (p->header.flag & BT_LEAF) {
+ /* return leftmost entry */
+ btsp = btstack->top;
+ btsp->bn = bn;
+ btsp->index = 0;
+ btsp->mp = mp;
+
+ return 0;
+ }
+
+ /*
+ * descend down to leftmost child page
+ */
+ /* push (bn, index) of the parent page/entry */
+ BT_PUSH(btstack, bn, 0);
+
+ /* get the leftmost entry */
+ stbl = DT_GETSTBL(p);
+ xd = (pxd_t *) & p->slot[stbl[0]];
+
+ /* get the child page block address */
+ bn = addressPXD(xd);
+ psize = lengthPXD(xd) << JFS_SBI(ip->i_sb)->l2bsize;
+
+ /* unpin the parent page */
+ DT_PUTPAGE(mp);
+ }
+}
+
+
+/*
+ * dtReadNext()
+ *
+ * function: get the page of the specified offset (pn:index)
+ *
+ * return: if (offset > eof), bn = -1;
+ *
+ * note: if index > nextindex of the target leaf page,
+ * start with 1st entry of next leaf page;
+ */
+static int dtReadNext(struct inode *ip, loff_t * offset,
+ struct btstack * btstack)
+{
+ int rc = 0;
+ struct dtoffset {
+ s16 pn;
+ s16 index;
+ s32 unused;
+ } *dtoffset = (struct dtoffset *) offset;
+ s64 bn;
+ struct metapage *mp;
+ dtpage_t *p;
+ int index;
+ int pn;
+ s8 *stbl;
+ struct btframe *btsp, *parent;
+ pxd_t *xd;
+
+ /*
+ * get leftmost leaf page pinned
+ */
+ if ((rc = dtReadFirst(ip, btstack)))
+ return rc;
+
+ /* get leaf page */
+ DT_GETSEARCH(ip, btstack->top, bn, mp, p, index);
+
+ /* get the start offset (pn:index) */
+ pn = dtoffset->pn - 1; /* Now pn = 0 represents leftmost leaf */
+ index = dtoffset->index;
+
+ /* start at leftmost page ? */
+ if (pn == 0) {
+ /* offset beyond eof ? */
+ if (index < p->header.nextindex)
+ goto out;
+
+ if (p->header.flag & BT_ROOT) {
+ bn = -1;
+ goto out;
+ }
+
+ /* start with 1st entry of next leaf page */
+ dtoffset->pn++;
+ dtoffset->index = index = 0;
+ goto a;
+ }
+
+ /* start at non-leftmost page: scan parent pages for large pn */
+ if (p->header.flag & BT_ROOT) {
+ bn = -1;
+ goto out;
+ }
+
+ /* start after next leaf page ? */
+ if (pn > 1)
+ goto b;
+
+ /* get leaf page pn = 1 */
+ a:
+ bn = le64_to_cpu(p->header.next);
+
+ /* unpin leaf page */
+ DT_PUTPAGE(mp);
+
+ /* offset beyond eof ? */
+ if (bn == 0) {
+ bn = -1;
+ goto out;
+ }
+
+ goto c;
+
+ /*
+ * scan last internal page level to get target leaf page
+ */
+ b:
+ /* unpin leftmost leaf page */
+ DT_PUTPAGE(mp);
+
+ /* get left most parent page */
+ btsp = btstack->top;
+ parent = btsp - 1;
+ bn = parent->bn;
+ DT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+ if (rc)
+ return rc;
+
+ /* scan parent pages at last internal page level */
+ while (pn >= p->header.nextindex) {
+ pn -= p->header.nextindex;
+
+ /* get next parent page address */
+ bn = le64_to_cpu(p->header.next);
+
+ /* unpin current parent page */
+ DT_PUTPAGE(mp);
+
+ /* offset beyond eof ? */
+ if (bn == 0) {
+ bn = -1;
+ goto out;
+ }
+
+ /* get next parent page */
+ DT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+ if (rc)
+ return rc;
+
+ /* update parent page stack frame */
+ parent->bn = bn;
+ }
+
+ /* get leaf page address */
+ stbl = DT_GETSTBL(p);
+ xd = (pxd_t *) & p->slot[stbl[pn]];
+ bn = addressPXD(xd);
+
+ /* unpin parent page */
+ DT_PUTPAGE(mp);
+
+ /*
+ * get target leaf page
+ */
+ c:
+ DT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+ if (rc)
+ return rc;
+
+ /*
+ * leaf page has been completed:
+ * start with 1st entry of next leaf page
+ */
+ if (index >= p->header.nextindex) {
+ bn = le64_to_cpu(p->header.next);
+
+ /* unpin leaf page */
+ DT_PUTPAGE(mp);
+
+ /* offset beyond eof ? */
+ if (bn == 0) {
+ bn = -1;
+ goto out;
+ }
+
+ /* get next leaf page */
+ DT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+ if (rc)
+ return rc;
+
+ /* start with 1st entry of next leaf page */
+ dtoffset->pn++;
+ dtoffset->index = 0;
+ }
+
+ out:
+ /* return target leaf page pinned */
+ btsp = btstack->top;
+ btsp->bn = bn;
+ btsp->index = dtoffset->index;
+ btsp->mp = mp;
+
+ return 0;
+}
+
+
+/*
+ * dtCompare()
+ *
+ * function: compare search key with an internal entry
+ *
+ * return:
+ * < 0 if k is < record
+ * = 0 if k is = record
+ * > 0 if k is > record
+ */
+static int dtCompare(struct component_name * key, /* search key */
+ dtpage_t * p, /* directory page */
+ int si)
+{ /* entry slot index */
+ wchar_t *kname, *name;
+ int klen, namlen, len, rc;
+ struct idtentry *ih;
+ struct dtslot *t;
+
+ /*
+ * force the left-most key on internal pages, at any level of
+ * the tree, to be less than any search key.
+ * this obviates having to update the leftmost key on an internal
+ * page when the user inserts a new key in the tree smaller than
+ * anything that has been stored.
+ *
+ * (? if/when dtSearch() narrows down to 1st entry (index = 0),
+ * at any internal page at any level of the tree,
+ * it descends to child of the entry anyway -
+ * ? make the entry as min size dummy entry)
+ *
+ * if (e->index == 0 && h->prevpg == P_INVALID && !(h->flags & BT_LEAF))
+ * return (1);
+ */
+
+ kname = key->name;
+ klen = key->namlen;
+
+ ih = (struct idtentry *) & p->slot[si];
+ si = ih->next;
+ name = ih->name;
+ namlen = ih->namlen;
+ len = min(namlen, DTIHDRDATALEN);
+
+ /* compare with head/only segment */
+ len = min(klen, len);
+ if ((rc = UniStrncmp_le(kname, name, len)))
+ return rc;
+
+ klen -= len;
+ namlen -= len;
+
+ /* compare with additional segment(s) */
+ kname += len;
+ while (klen > 0 && namlen > 0) {
+ /* compare with next name segment */
+ t = (struct dtslot *) & p->slot[si];
+ len = min(namlen, DTSLOTDATALEN);
+ len = min(klen, len);
+ name = t->name;
+ if ((rc = UniStrncmp_le(kname, name, len)))
+ return rc;
+
+ klen -= len;
+ namlen -= len;
+ kname += len;
+ si = t->next;
+ }
+
+ return (klen - namlen);
+}
+
+
+
+
+/*
+ * ciCompare()
+ *
+ * function: compare search key with an (leaf/internal) entry
+ *
+ * return:
+ * < 0 if k is < record
+ * = 0 if k is = record
+ * > 0 if k is > record
+ */
+static int ciCompare(struct component_name * key, /* search key */
+ dtpage_t * p, /* directory page */
+ int si, /* entry slot index */
+ int flag)
+{
+ wchar_t *kname, *name, x;
+ int klen, namlen, len, rc;
+ struct ldtentry *lh;
+ struct idtentry *ih;
+ struct dtslot *t;
+ int i;
+
+ /*
+ * force the left-most key on internal pages, at any level of
+ * the tree, to be less than any search key.
+ * this obviates having to update the leftmost key on an internal
+ * page when the user inserts a new key in the tree smaller than
+ * anything that has been stored.
+ *
+ * (? if/when dtSearch() narrows down to 1st entry (index = 0),
+ * at any internal page at any level of the tree,
+ * it descends to child of the entry anyway -
+ * ? make the entry as min size dummy entry)
+ *
+ * if (e->index == 0 && h->prevpg == P_INVALID && !(h->flags & BT_LEAF))
+ * return (1);
+ */
+
+ kname = key->name;
+ klen = key->namlen;
+
+ /*
+ * leaf page entry
+ */
+ if (p->header.flag & BT_LEAF) {
+ lh = (struct ldtentry *) & p->slot[si];
+ si = lh->next;
+ name = lh->name;
+ namlen = lh->namlen;
+ if (flag & JFS_DIR_INDEX)
+ len = min(namlen, DTLHDRDATALEN);
+ else
+ len = min(namlen, DTLHDRDATALEN_LEGACY);
+ }
+ /*
+ * internal page entry
+ */
+ else {
+ ih = (struct idtentry *) & p->slot[si];
+ si = ih->next;
+ name = ih->name;
+ namlen = ih->namlen;
+ len = min(namlen, DTIHDRDATALEN);
+ }
+
+ /* compare with head/only segment */
+ len = min(klen, len);
+ for (i = 0; i < len; i++, kname++, name++) {
+ /* only uppercase if case-insensitive support is on */
+ if ((flag & JFS_OS2) == JFS_OS2)
+ x = UniToupper(le16_to_cpu(*name));
+ else
+ x = le16_to_cpu(*name);
+ if ((rc = *kname - x))
+ return rc;
+ }
+
+ klen -= len;
+ namlen -= len;
+
+ /* compare with additional segment(s) */
+ while (klen > 0 && namlen > 0) {
+ /* compare with next name segment */
+ t = (struct dtslot *) & p->slot[si];
+ len = min(namlen, DTSLOTDATALEN);
+ len = min(klen, len);
+ name = t->name;
+ for (i = 0; i < len; i++, kname++, name++) {
+ /* only uppercase if case-insensitive support is on */
+ if ((flag & JFS_OS2) == JFS_OS2)
+ x = UniToupper(le16_to_cpu(*name));
+ else
+ x = le16_to_cpu(*name);
+
+ if ((rc = *kname - x))
+ return rc;
+ }
+
+ klen -= len;
+ namlen -= len;
+ si = t->next;
+ }
+
+ return (klen - namlen);
+}
+
+
+/*
+ * ciGetLeafPrefixKey()
+ *
+ * function: compute prefix of suffix compression
+ * from two adjacent leaf entries
+ * across page boundary
+ *
+ * return:
+ * Number of prefix bytes needed to distinguish b from a.
+ */
+static void ciGetLeafPrefixKey(dtpage_t * lp, int li, dtpage_t * rp,
+ int ri, struct component_name * key, int flag)
+{
+ int klen, namlen;
+ wchar_t *pl, *pr, *kname;
+ wchar_t lname[JFS_NAME_MAX + 1];
+ struct component_name lkey = { 0, lname };
+ wchar_t rname[JFS_NAME_MAX + 1];
+ struct component_name rkey = { 0, rname };
+
+ /* get left and right key */
+ dtGetKey(lp, li, &lkey, flag);
+ lkey.name[lkey.namlen] = 0;
+
+ if ((flag & JFS_OS2) == JFS_OS2)
+ ciToUpper(&lkey);
+
+ dtGetKey(rp, ri, &rkey, flag);
+ rkey.name[rkey.namlen] = 0;
+
+
+ if ((flag & JFS_OS2) == JFS_OS2)
+ ciToUpper(&rkey);
+
+ /* compute prefix */
+ klen = 0;
+ kname = key->name;
+ namlen = min(lkey.namlen, rkey.namlen);
+ for (pl = lkey.name, pr = rkey.name;
+ namlen; pl++, pr++, namlen--, klen++, kname++) {
+ *kname = *pr;
+ if (*pl != *pr) {
+ key->namlen = klen + 1;
+ return;
+ }
+ }
+
+ /* l->namlen <= r->namlen since l <= r */
+ if (lkey.namlen < rkey.namlen) {
+ *kname = *pr;
+ key->namlen = klen + 1;
+ } else /* l->namelen == r->namelen */
+ key->namlen = klen;
+
+ return;
+}
+
+
+
+/*
+ * dtGetKey()
+ *
+ * function: get key of the entry
+ */
+static void dtGetKey(dtpage_t * p, int i, /* entry index */
+ struct component_name * key, int flag)
+{
+ int si;
+ s8 *stbl;
+ struct ldtentry *lh;
+ struct idtentry *ih;
+ struct dtslot *t;
+ int namlen, len;
+ wchar_t *name, *kname;
+
+ /* get entry */
+ stbl = DT_GETSTBL(p);
+ si = stbl[i];
+ if (p->header.flag & BT_LEAF) {
+ lh = (struct ldtentry *) & p->slot[si];
+ si = lh->next;
+ namlen = lh->namlen;
+ name = lh->name;
+ if (flag & JFS_DIR_INDEX)
+ len = min(namlen, DTLHDRDATALEN);
+ else
+ len = min(namlen, DTLHDRDATALEN_LEGACY);
+ } else {
+ ih = (struct idtentry *) & p->slot[si];
+ si = ih->next;
+ namlen = ih->namlen;
+ name = ih->name;
+ len = min(namlen, DTIHDRDATALEN);
+ }
+
+ key->namlen = namlen;
+ kname = key->name;
+
+ /*
+ * move head/only segment
+ */
+ UniStrncpy_le(kname, name, len);
+
+ /*
+ * move additional segment(s)
+ */
+ while (si >= 0) {
+ /* get next segment */
+ t = &p->slot[si];
+ kname += len;
+ namlen -= len;
+ len = min(namlen, DTSLOTDATALEN);
+ UniStrncpy_le(kname, t->name, len);
+
+ si = t->next;
+ }
+}
+
+
+/*
+ * dtInsertEntry()
+ *
+ * function: allocate free slot(s) and
+ * write a leaf/internal entry
+ *
+ * return: entry slot index
+ */
+static void dtInsertEntry(dtpage_t * p, int index, struct component_name * key,
+ ddata_t * data, struct dt_lock ** dtlock)
+{
+ struct dtslot *h, *t;
+ struct ldtentry *lh = 0;
+ struct idtentry *ih = 0;
+ int hsi, fsi, klen, len, nextindex;
+ wchar_t *kname, *name;
+ s8 *stbl;
+ pxd_t *xd;
+ struct dt_lock *dtlck = *dtlock;
+ struct lv *lv;
+ int xsi, n;
+ s64 bn = 0;
+ struct metapage *mp = 0;
+
+ klen = key->namlen;
+ kname = key->name;
+
+ /* allocate a free slot */
+ hsi = fsi = p->header.freelist;
+ h = &p->slot[fsi];
+ p->header.freelist = h->next;
+ --p->header.freecnt;
+
+ /* open new linelock */
+ if (dtlck->index >= dtlck->maxcnt)
+ dtlck = (struct dt_lock *) txLinelock(dtlck);
+
+ lv = & dtlck->lv[dtlck->index];
+ lv->offset = hsi;
+
+ /* write head/only segment */
+ if (p->header.flag & BT_LEAF) {
+ lh = (struct ldtentry *) h;
+ lh->next = h->next;
+ lh->inumber = data->leaf.ino; /* little-endian */
+ lh->namlen = klen;
+ name = lh->name;
+ if (data->leaf.ip) {
+ len = min(klen, DTLHDRDATALEN);
+ if (!(p->header.flag & BT_ROOT))
+ bn = addressPXD(&p->header.self);
+ lh->index = cpu_to_le32(add_index(data->leaf.tid,
+ data->leaf.ip,
+ bn, index));
+ } else
+ len = min(klen, DTLHDRDATALEN_LEGACY);
+ } else {
+ ih = (struct idtentry *) h;
+ ih->next = h->next;
+ xd = (pxd_t *) ih;
+ *xd = data->xd;
+ ih->namlen = klen;
+ name = ih->name;
+ len = min(klen, DTIHDRDATALEN);
+ }
+
+ UniStrncpy_le(name, kname, len);
+
+ n = 1;
+ xsi = hsi;
+
+ /* write additional segment(s) */
+ t = h;
+ klen -= len;
+ while (klen) {
+ /* get free slot */
+ fsi = p->header.freelist;
+ t = &p->slot[fsi];
+ p->header.freelist = t->next;
+ --p->header.freecnt;
+
+ /* is next slot contiguous ? */
+ if (fsi != xsi + 1) {
+ /* close current linelock */
+ lv->length = n;
+ dtlck->index++;
+
+ /* open new linelock */
+ if (dtlck->index < dtlck->maxcnt)
+ lv++;
+ else {
+ dtlck = (struct dt_lock *) txLinelock(dtlck);
+ lv = & dtlck->lv[0];
+ }
+
+ lv->offset = fsi;
+ n = 0;
+ }
+
+ kname += len;
+ len = min(klen, DTSLOTDATALEN);
+ UniStrncpy_le(t->name, kname, len);
+
+ n++;
+ xsi = fsi;
+ klen -= len;
+ }
+
+ /* close current linelock */
+ lv->length = n;
+ dtlck->index++;
+
+ *dtlock = dtlck;
+
+ /* terminate last/only segment */
+ if (h == t) {
+ /* single segment entry */
+ if (p->header.flag & BT_LEAF)
+ lh->next = -1;
+ else
+ ih->next = -1;
+ } else
+ /* multi-segment entry */
+ t->next = -1;
+
+ /* if insert into middle, shift right succeeding entries in stbl */
+ stbl = DT_GETSTBL(p);
+ nextindex = p->header.nextindex;
+ if (index < nextindex) {
+ memmove(stbl + index + 1, stbl + index, nextindex - index);
+
+ if ((p->header.flag & BT_LEAF) && data->leaf.ip) {
+ /*
+ * Need to update slot number for entries that moved
+ * in the stbl
+ */
+ mp = 0;
+ for (n = index + 1; n <= nextindex; n++) {
+ lh = (struct ldtentry *) & (p->slot[stbl[n]]);
+ modify_index(data->leaf.tid, data->leaf.ip,
+ le32_to_cpu(lh->index), bn, n,
+ &mp);
+ }
+ if (mp)
+ release_metapage(mp);
+ }
+ }
+
+ stbl[index] = hsi;
+
+ /* advance next available entry index of stbl */
+ ++p->header.nextindex;
+}
+
+
+/*
+ * dtMoveEntry()
+ *
+ * function: move entries from split/left page to new/right page
+ *
+ * nextindex of dst page and freelist/freecnt of both pages
+ * are updated.
+ */
+static void dtMoveEntry(dtpage_t * sp, int si, dtpage_t * dp,
+ struct dt_lock ** sdtlock, struct dt_lock ** ddtlock,
+ int do_index)
+{
+ int ssi, next; /* src slot index */
+ int di; /* dst entry index */
+ int dsi; /* dst slot index */
+ s8 *sstbl, *dstbl; /* sorted entry table */
+ int snamlen, len;
+ struct ldtentry *slh, *dlh = 0;
+ struct idtentry *sih, *dih = 0;
+ struct dtslot *h, *s, *d;
+ struct dt_lock *sdtlck = *sdtlock, *ddtlck = *ddtlock;
+ struct lv *slv, *dlv;
+ int xssi, ns, nd;
+ int sfsi;
+
+ sstbl = (s8 *) & sp->slot[sp->header.stblindex];
+ dstbl = (s8 *) & dp->slot[dp->header.stblindex];
+
+ dsi = dp->header.freelist; /* first (whole page) free slot */
+ sfsi = sp->header.freelist;
+
+ /* linelock destination entry slot */
+ dlv = & ddtlck->lv[ddtlck->index];
+ dlv->offset = dsi;
+
+ /* linelock source entry slot */
+ slv = & sdtlck->lv[sdtlck->index];
+ slv->offset = sstbl[si];
+ xssi = slv->offset - 1;
+
+ /*
+ * move entries
+ */
+ ns = nd = 0;
+ for (di = 0; si < sp->header.nextindex; si++, di++) {
+ ssi = sstbl[si];
+ dstbl[di] = dsi;
+
+ /* is next slot contiguous ? */
+ if (ssi != xssi + 1) {
+ /* close current linelock */
+ slv->length = ns;
+ sdtlck->index++;
+
+ /* open new linelock */
+ if (sdtlck->index < sdtlck->maxcnt)
+ slv++;
+ else {
+ sdtlck = (struct dt_lock *) txLinelock(sdtlck);
+ slv = & sdtlck->lv[0];
+ }
+
+ slv->offset = ssi;
+ ns = 0;
+ }
+
+ /*
+ * move head/only segment of an entry
+ */
+ /* get dst slot */
+ h = d = &dp->slot[dsi];
+
+ /* get src slot and move */
+ s = &sp->slot[ssi];
+ if (sp->header.flag & BT_LEAF) {
+ /* get source entry */
+ slh = (struct ldtentry *) s;
+ dlh = (struct ldtentry *) h;
+ snamlen = slh->namlen;
+
+ if (do_index) {
+ len = min(snamlen, DTLHDRDATALEN);
+ dlh->index = slh->index; /* little-endian */
+ } else
+ len = min(snamlen, DTLHDRDATALEN_LEGACY);
+
+ memcpy(dlh, slh, 6 + len * 2);
+
+ next = slh->next;
+
+ /* update dst head/only segment next field */
+ dsi++;
+ dlh->next = dsi;
+ } else {
+ sih = (struct idtentry *) s;
+ snamlen = sih->namlen;
+
+ len = min(snamlen, DTIHDRDATALEN);
+ dih = (struct idtentry *) h;
+ memcpy(dih, sih, 10 + len * 2);
+ next = sih->next;
+
+ dsi++;
+ dih->next = dsi;
+ }
+
+ /* free src head/only segment */
+ s->next = sfsi;
+ s->cnt = 1;
+ sfsi = ssi;
+
+ ns++;
+ nd++;
+ xssi = ssi;
+
+ /*
+ * move additional segment(s) of the entry
+ */
+ snamlen -= len;
+ while ((ssi = next) >= 0) {
+ /* is next slot contiguous ? */
+ if (ssi != xssi + 1) {
+ /* close current linelock */
+ slv->length = ns;
+ sdtlck->index++;
+
+ /* open new linelock */
+ if (sdtlck->index < sdtlck->maxcnt)
+ slv++;
+ else {
+ sdtlck =
+ (struct dt_lock *)
+ txLinelock(sdtlck);
+ slv = & sdtlck->lv[0];
+ }
+
+ slv->offset = ssi;
+ ns = 0;
+ }
+
+ /* get next source segment */
+ s = &sp->slot[ssi];
+
+ /* get next destination free slot */
+ d++;
+
+ len = min(snamlen, DTSLOTDATALEN);
+ UniStrncpy(d->name, s->name, len);
+
+ ns++;
+ nd++;
+ xssi = ssi;
+
+ dsi++;
+ d->next = dsi;
+
+ /* free source segment */
+ next = s->next;
+ s->next = sfsi;
+ s->cnt = 1;
+ sfsi = ssi;
+
+ snamlen -= len;
+ } /* end while */
+
+ /* terminate dst last/only segment */
+ if (h == d) {
+ /* single segment entry */
+ if (dp->header.flag & BT_LEAF)
+ dlh->next = -1;
+ else
+ dih->next = -1;
+ } else
+ /* multi-segment entry */
+ d->next = -1;
+ } /* end for */
+
+ /* close current linelock */
+ slv->length = ns;
+ sdtlck->index++;
+ *sdtlock = sdtlck;
+
+ dlv->length = nd;
+ ddtlck->index++;
+ *ddtlock = ddtlck;
+
+ /* update source header */
+ sp->header.freelist = sfsi;
+ sp->header.freecnt += nd;
+
+ /* update destination header */
+ dp->header.nextindex = di;
+
+ dp->header.freelist = dsi;
+ dp->header.freecnt -= nd;
+}
+
+
+/*
+ * dtDeleteEntry()
+ *
+ * function: free a (leaf/internal) entry
+ *
+ * log freelist header, stbl, and each segment slot of entry
+ * (even though last/only segment next field is modified,
+ * physical image logging requires all segment slots of
+ * the entry logged to avoid applying previous updates
+ * to the same slots)
+ */
+static void dtDeleteEntry(dtpage_t * p, int fi, struct dt_lock ** dtlock)
+{
+ int fsi; /* free entry slot index */
+ s8 *stbl;
+ struct dtslot *t;
+ int si, freecnt;
+ struct dt_lock *dtlck = *dtlock;
+ struct lv *lv;
+ int xsi, n;
+
+ /* get free entry slot index */
+ stbl = DT_GETSTBL(p);
+ fsi = stbl[fi];
+
+ /* open new linelock */
+ if (dtlck->index >= dtlck->maxcnt)
+ dtlck = (struct dt_lock *) txLinelock(dtlck);
+ lv = & dtlck->lv[dtlck->index];
+
+ lv->offset = fsi;
+
+ /* get the head/only segment */
+ t = &p->slot[fsi];
+ if (p->header.flag & BT_LEAF)
+ si = ((struct ldtentry *) t)->next;
+ else
+ si = ((struct idtentry *) t)->next;
+ t->next = si;
+ t->cnt = 1;
+
+ n = freecnt = 1;
+ xsi = fsi;
+
+ /* find the last/only segment */
+ while (si >= 0) {
+ /* is next slot contiguous ? */
+ if (si != xsi + 1) {
+ /* close current linelock */
+ lv->length = n;
+ dtlck->index++;
+
+ /* open new linelock */
+ if (dtlck->index < dtlck->maxcnt)
+ lv++;
+ else {
+ dtlck = (struct dt_lock *) txLinelock(dtlck);
+ lv = & dtlck->lv[0];
+ }
+
+ lv->offset = si;
+ n = 0;
+ }
+
+ n++;
+ xsi = si;
+ freecnt++;
+
+ t = &p->slot[si];
+ t->cnt = 1;
+ si = t->next;
+ }
+
+ /* close current linelock */
+ lv->length = n;
+ dtlck->index++;
+
+ *dtlock = dtlck;
+
+ /* update freelist */
+ t->next = p->header.freelist;
+ p->header.freelist = fsi;
+ p->header.freecnt += freecnt;
+
+ /* if delete from middle,
+ * shift left the succedding entries in the stbl
+ */
+ si = p->header.nextindex;
+ if (fi < si - 1)
+ memmove(&stbl[fi], &stbl[fi + 1], si - fi - 1);
+
+ p->header.nextindex--;
+}
+
+
+/*
+ * dtTruncateEntry()
+ *
+ * function: truncate a (leaf/internal) entry
+ *
+ * log freelist header, stbl, and each segment slot of entry
+ * (even though last/only segment next field is modified,
+ * physical image logging requires all segment slots of
+ * the entry logged to avoid applying previous updates
+ * to the same slots)
+ */
+static void dtTruncateEntry(dtpage_t * p, int ti, struct dt_lock ** dtlock)
+{
+ int tsi; /* truncate entry slot index */
+ s8 *stbl;
+ struct dtslot *t;
+ int si, freecnt;
+ struct dt_lock *dtlck = *dtlock;
+ struct lv *lv;
+ int fsi, xsi, n;
+
+ /* get free entry slot index */
+ stbl = DT_GETSTBL(p);
+ tsi = stbl[ti];
+
+ /* open new linelock */
+ if (dtlck->index >= dtlck->maxcnt)
+ dtlck = (struct dt_lock *) txLinelock(dtlck);
+ lv = & dtlck->lv[dtlck->index];
+
+ lv->offset = tsi;
+
+ /* get the head/only segment */
+ t = &p->slot[tsi];
+ ASSERT(p->header.flag & BT_INTERNAL);
+ ((struct idtentry *) t)->namlen = 0;
+ si = ((struct idtentry *) t)->next;
+ ((struct idtentry *) t)->next = -1;
+
+ n = 1;
+ freecnt = 0;
+ fsi = si;
+ xsi = tsi;
+
+ /* find the last/only segment */
+ while (si >= 0) {
+ /* is next slot contiguous ? */
+ if (si != xsi + 1) {
+ /* close current linelock */
+ lv->length = n;
+ dtlck->index++;
+
+ /* open new linelock */
+ if (dtlck->index < dtlck->maxcnt)
+ lv++;
+ else {
+ dtlck = (struct dt_lock *) txLinelock(dtlck);
+ lv = & dtlck->lv[0];
+ }
+
+ lv->offset = si;
+ n = 0;
+ }
+
+ n++;
+ xsi = si;
+ freecnt++;
+
+ t = &p->slot[si];
+ t->cnt = 1;
+ si = t->next;
+ }
+
+ /* close current linelock */
+ lv->length = n;
+ dtlck->index++;
+
+ *dtlock = dtlck;
+
+ /* update freelist */
+ if (freecnt == 0)
+ return;
+ t->next = p->header.freelist;
+ p->header.freelist = fsi;
+ p->header.freecnt += freecnt;
+}
+
+
+/*
+ * dtLinelockFreelist()
+ */
+static void dtLinelockFreelist(dtpage_t * p, /* directory page */
+ int m, /* max slot index */
+ struct dt_lock ** dtlock)
+{
+ int fsi; /* free entry slot index */
+ struct dtslot *t;
+ int si;
+ struct dt_lock *dtlck = *dtlock;
+ struct lv *lv;
+ int xsi, n;
+
+ /* get free entry slot index */
+ fsi = p->header.freelist;
+
+ /* open new linelock */
+ if (dtlck->index >= dtlck->maxcnt)
+ dtlck = (struct dt_lock *) txLinelock(dtlck);
+ lv = & dtlck->lv[dtlck->index];
+
+ lv->offset = fsi;
+
+ n = 1;
+ xsi = fsi;
+
+ t = &p->slot[fsi];
+ si = t->next;
+
+ /* find the last/only segment */
+ while (si < m && si >= 0) {
+ /* is next slot contiguous ? */
+ if (si != xsi + 1) {
+ /* close current linelock */
+ lv->length = n;
+ dtlck->index++;
+
+ /* open new linelock */
+ if (dtlck->index < dtlck->maxcnt)
+ lv++;
+ else {
+ dtlck = (struct dt_lock *) txLinelock(dtlck);
+ lv = & dtlck->lv[0];
+ }
+
+ lv->offset = si;
+ n = 0;
+ }
+
+ n++;
+ xsi = si;
+
+ t = &p->slot[si];
+ si = t->next;
+ }
+
+ /* close current linelock */
+ lv->length = n;
+ dtlck->index++;
+
+ *dtlock = dtlck;
+}
+
+
+/*
+ * NAME: dtModify
+ *
+ * FUNCTION: Modify the inode number part of a directory entry
+ *
+ * PARAMETERS:
+ * tid - Transaction id
+ * ip - Inode of parent directory
+ * key - Name of entry to be modified
+ * orig_ino - Original inode number expected in entry
+ * new_ino - New inode number to put into entry
+ * flag - JFS_RENAME
+ *
+ * RETURNS:
+ * ESTALE - If entry found does not match orig_ino passed in
+ * ENOENT - If no entry can be found to match key
+ * 0 - If successfully modified entry
+ */
+int dtModify(tid_t tid, struct inode *ip,
+ struct component_name * key, ino_t * orig_ino, ino_t new_ino, int flag)
+{
+ int rc;
+ s64 bn;
+ struct metapage *mp;
+ dtpage_t *p;
+ int index;
+ struct btstack btstack;
+ struct tlock *tlck;
+ struct dt_lock *dtlck;
+ struct lv *lv;
+ s8 *stbl;
+ int entry_si; /* entry slot index */
+ struct ldtentry *entry;
+
+ /*
+ * search for the entry to modify:
+ *
+ * dtSearch() returns (leaf page pinned, index at which to modify).
+ */
+ if ((rc = dtSearch(ip, key, orig_ino, &btstack, flag)))
+ return rc;
+
+ /* retrieve search result */
+ DT_GETSEARCH(ip, btstack.top, bn, mp, p, index);
+
+ BT_MARK_DIRTY(mp, ip);
+ /*
+ * acquire a transaction lock on the leaf page of named entry
+ */
+ tlck = txLock(tid, ip, mp, tlckDTREE | tlckENTRY);
+ dtlck = (struct dt_lock *) & tlck->lock;
+
+ /* get slot index of the entry */
+ stbl = DT_GETSTBL(p);
+ entry_si = stbl[index];
+
+ /* linelock entry */
+ ASSERT(dtlck->index == 0);
+ lv = & dtlck->lv[0];
+ lv->offset = entry_si;
+ lv->length = 1;
+ dtlck->index++;
+
+ /* get the head/only segment */
+ entry = (struct ldtentry *) & p->slot[entry_si];
+
+ /* substitute the inode number of the entry */
+ entry->inumber = cpu_to_le32(new_ino);
+
+ /* unpin the leaf page */
+ DT_PUTPAGE(mp);
+
+ return 0;
+}
+
+#ifdef _JFS_DEBUG_DTREE
+/*
+ * dtDisplayTree()
+ *
+ * function: traverse forward
+ */
+int dtDisplayTree(struct inode *ip)
+{
+ int rc;
+ struct metapage *mp;
+ dtpage_t *p;
+ s64 bn, pbn;
+ int index, lastindex, v, h;
+ pxd_t *xd;
+ struct btstack btstack;
+ struct btframe *btsp;
+ struct btframe *parent;
+ u8 *stbl;
+ int psize = 256;
+
+ printk("display B+-tree.\n");
+
+ /* clear stack */
+ btsp = btstack.stack;
+
+ /*
+ * start with root
+ *
+ * root resides in the inode
+ */
+ bn = 0;
+ v = h = 0;
+
+ /*
+ * first access of each page:
+ */
+ newPage:
+ DT_GETPAGE(ip, bn, mp, psize, p, rc);
+ if (rc)
+ return rc;
+
+ /* process entries forward from first index */
+ index = 0;
+ lastindex = p->header.nextindex - 1;
+
+ if (p->header.flag & BT_INTERNAL) {
+ /*
+ * first access of each internal page
+ */
+ printf("internal page ");
+ dtDisplayPage(ip, bn, p);
+
+ goto getChild;
+ } else { /* (p->header.flag & BT_LEAF) */
+
+ /*
+ * first access of each leaf page
+ */
+ printf("leaf page ");
+ dtDisplayPage(ip, bn, p);
+
+ /*
+ * process leaf page entries
+ *
+ for ( ; index <= lastindex; index++)
+ {
+ }
+ */
+
+ /* unpin the leaf page */
+ DT_PUTPAGE(mp);
+ }
+
+ /*
+ * go back up to the parent page
+ */
+ getParent:
+ /* pop/restore parent entry for the current child page */
+ if ((parent = (btsp == btstack.stack ? NULL : --btsp)) == NULL)
+ /* current page must have been root */
+ return;
+
+ /*
+ * parent page scan completed
+ */
+ if ((index = parent->index) == (lastindex = parent->lastindex)) {
+ /* go back up to the parent page */
+ goto getParent;
+ }
+
+ /*
+ * parent page has entries remaining
+ */
+ /* get back the parent page */
+ bn = parent->bn;
+ /* v = parent->level; */
+ DT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+ if (rc)
+ return rc;
+
+ /* get next parent entry */
+ index++;
+
+ /*
+ * internal page: go down to child page of current entry
+ */
+ getChild:
+ /* push/save current parent entry for the child page */
+ btsp->bn = pbn = bn;
+ btsp->index = index;
+ btsp->lastindex = lastindex;
+ /* btsp->level = v; */
+ /* btsp->node = h; */
+ ++btsp;
+
+ /* get current entry for the child page */
+ stbl = DT_GETSTBL(p);
+ xd = (pxd_t *) & p->slot[stbl[index]];
+
+ /*
+ * first access of each internal entry:
+ */
+
+ /* get child page */
+ bn = addressPXD(xd);
+ psize = lengthPXD(xd) << ip->i_ipmnt->i_l2bsize;
+
+ printk("traverse down 0x%Lx[%d]->0x%Lx\n", pbn, index, bn);
+ v++;
+ h = index;
+
+ /* release parent page */
+ DT_PUTPAGE(mp);
+
+ /* process the child page */
+ goto newPage;
+}
+
+
+/*
+ * dtDisplayPage()
+ *
+ * function: display page
+ */
+int dtDisplayPage(struct inode *ip, s64 bn, dtpage_t * p)
+{
+ int rc;
+ struct metapage *mp;
+ struct ldtentry *lh;
+ struct idtentry *ih;
+ pxd_t *xd;
+ int i, j;
+ u8 *stbl;
+ wchar_t name[JFS_NAME_MAX + 1];
+ struct component_name key = { 0, name };
+ int freepage = 0;
+
+ if (p == NULL) {
+ freepage = 1;
+ DT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
+ if (rc)
+ return rc;
+ }
+
+ /* display page control */
+ printk("bn:0x%Lx flag:0x%08x nextindex:%d\n",
+ bn, p->header.flag, p->header.nextindex);
+
+ /* display entries */
+ stbl = DT_GETSTBL(p);
+ for (i = 0, j = 1; i < p->header.nextindex; i++, j++) {
+ dtGetKey(p, i, &key, JFS_SBI(ip->i_sb)->mntflag);
+ key.name[key.namlen] = '\0';
+ if (p->header.flag & BT_LEAF) {
+ lh = (struct ldtentry *) & p->slot[stbl[i]];
+ printf("\t[%d] %s:%d", i, key.name,
+ le32_to_cpu(lh->inumber));
+ } else {
+ ih = (struct idtentry *) & p->slot[stbl[i]];
+ xd = (pxd_t *) ih;
+ bn = addressPXD(xd);
+ printf("\t[%d] %s:0x%Lx", i, key.name, bn);
+ }
+
+ if (j == 4) {
+ printf("\n");
+ j = 0;
+ }
+ }
+
+ printf("\n");
+
+ if (freepage)
+ DT_PUTPAGE(mp);
+
+ return 0;
+}
+#endif /* _JFS_DEBUG_DTREE */
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)