| /* |
| * Copyright (C) International Business Machines Corp., 2000-2004 |
| * |
| * 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 <linux/quotaops.h> |
| #include <linux/slab.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)))\ |
| {\ |
| BT_PUTPAGE(MP);\ |
| jfs_error((IP)->i_sb, "DT_GETPAGE: dtree page corrupt");\ |
| 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 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 int 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) |
| |
| /* |
| * read_index_page() |
| * |
| * Reads a page of a directory's index table. |
| * Having metadata mapped into the directory inode's address space |
| * presents a multitude of problems. We avoid this by mapping to |
| * the absolute address space outside of the *_metapage routines |
| */ |
| static struct metapage *read_index_page(struct inode *inode, s64 blkno) |
| { |
| int rc; |
| s64 xaddr; |
| int xflag; |
| s32 xlen; |
| |
| rc = xtLookup(inode, blkno, 1, &xflag, &xaddr, &xlen, 1); |
| if (rc || (xaddr == 0)) |
| return NULL; |
| |
| return read_metapage(inode, xaddr, PSIZE, 1); |
| } |
| |
| /* |
| * get_index_page() |
| * |
| * Same as get_index_page(), but get's a new page without reading |
| */ |
| static struct metapage *get_index_page(struct inode *inode, s64 blkno) |
| { |
| int rc; |
| s64 xaddr; |
| int xflag; |
| s32 xlen; |
| |
| rc = xtLookup(inode, blkno, 1, &xflag, &xaddr, &xlen, 1); |
| if (rc || (xaddr == 0)) |
| return NULL; |
| |
| return get_metapage(inode, xaddr, PSIZE, 1); |
| } |
| |
| /* |
| * 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, s64 *lblock) |
| { |
| 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) { |
| jfs_warn("find_entry called with index = %d", index); |
| maxWarnings--; |
| } |
| return NULL; |
| } |
| |
| if (index >= jfs_ip->next_index) { |
| jfs_warn("find_entry called with index >= next_index"); |
| return NULL; |
| } |
| |
| if (jfs_dirtable_inline(ip)) { |
| /* |
| * Inline directory table |
| */ |
| *mp = NULL; |
| 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 && (*lblock != blkno)) { |
| release_metapage(*mp); |
| *mp = NULL; |
| } |
| if (!(*mp)) { |
| *lblock = blkno; |
| *mp = read_index_page(ip, blkno); |
| } |
| if (!(*mp)) { |
| jfs_err("free_index: error reading directory table"); |
| return NULL; |
| } |
| |
| 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; |
| struct tlock *tlck; |
| s64 xaddr; |
| |
| ASSERT(DO_INDEX(ip)); |
| |
| if (jfs_ip->next_index < 2) { |
| jfs_warn("add_index: next_index = %d. Resetting!", |
| 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)) { |
| struct dir_table_slot temp_table[12]; |
| |
| /* |
| * It's time to move the inline table to an external |
| * page and begin to build the xtree |
| */ |
| if (dquot_alloc_block(ip, sbi->nbperpage)) |
| goto clean_up; |
| if (dbAlloc(ip, 0, sbi->nbperpage, &xaddr)) { |
| dquot_free_block(ip, sbi->nbperpage); |
| goto clean_up; |
| } |
| |
| /* |
| * Save the table, we're going to overwrite it with the |
| * xtree root |
| */ |
| memcpy(temp_table, &jfs_ip->i_dirtable, sizeof(temp_table)); |
| |
| /* |
| * Initialize empty x-tree |
| */ |
| xtInitRoot(tid, ip); |
| |
| /* |
| * Add the first block to the xtree |
| */ |
| if (xtInsert(tid, ip, 0, 0, sbi->nbperpage, &xaddr, 0)) { |
| /* This really shouldn't fail */ |
| jfs_warn("add_index: xtInsert failed!"); |
| memcpy(&jfs_ip->i_dirtable, temp_table, |
| sizeof (temp_table)); |
| dbFree(ip, xaddr, sbi->nbperpage); |
| dquot_free_block(ip, sbi->nbperpage); |
| goto clean_up; |
| } |
| ip->i_size = PSIZE; |
| |
| mp = get_index_page(ip, 0); |
| if (!mp) { |
| jfs_err("add_index: get_metapage failed!"); |
| xtTruncate(tid, ip, 0, COMMIT_PWMAP); |
| memcpy(&jfs_ip->i_dirtable, temp_table, |
| sizeof (temp_table)); |
| goto clean_up; |
| } |
| 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 (xtInsert(tid, ip, 0, blkno, sbi->nbperpage, &xaddr, 0)) { |
| jfs_warn("add_index: xtInsert failed!"); |
| goto clean_up; |
| } |
| ip->i_size += PSIZE; |
| |
| if ((mp = get_index_page(ip, blkno))) |
| memset(mp->data, 0, PSIZE); /* Just looks better */ |
| else |
| xtTruncate(tid, ip, offset, COMMIT_PWMAP); |
| } else |
| mp = read_index_page(ip, blkno); |
| |
| if (!mp) { |
| jfs_err("add_index: get/read_metapage failed!"); |
| goto clean_up; |
| } |
| |
| 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; |
| |
| clean_up: |
| |
| jfs_ip->next_index--; |
| |
| return 0; |
| } |
| |
| /* |
| * 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; |
| s64 lblock; |
| struct metapage *mp = NULL; |
| |
| dirtab_slot = find_index(ip, index, &mp, &lblock); |
| |
| if (!dirtab_slot) |
| 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, s64 *lblock) |
| { |
| struct dir_table_slot *dirtab_slot; |
| |
| dirtab_slot = find_index(ip, index, mp, lblock); |
| |
| if (!dirtab_slot) |
| 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) |
| { |
| s64 lblock; |
| struct metapage *mp = NULL; |
| struct dir_table_slot *slot; |
| |
| slot = find_index(ip, index, &mp, &lblock); |
| if (!slot) { |
| 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 = kmalloc((JFS_NAME_MAX + 1) * sizeof(wchar_t), GFP_NOFS); |
| if (!ciKey.name) { |
| 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 (BT_STACK_FULL(btstack)) { |
| /* Something's corrupted, mark filesystem dirty so |
| * chkdsk will fix it. |
| */ |
| jfs_error(sb, "stack overrun in dtSearch!"); |
| BT_STACK_DUMP(btstack); |
| 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 = NULL; /* signifies legacy directory format */ |
| } |
| data.leaf.ino = *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, NULL }; |
| ddata_t *data = split->data; |
| int n; |
| struct dt_lock *dtlck; |
| struct tlock *tlck; |
| struct lv *lv; |
| int quota_allocation = 0; |
| |
| /* get split page */ |
| smp = split->mp; |
| sp = DT_PAGE(ip, smp); |
| |
| key.name = kmalloc((JFS_NAME_MAX + 2) * sizeof(wchar_t), GFP_NOFS); |
| if (!key.name) { |
| 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))) { |
| DT_PUTPAGE(smp); |
| 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); |
| |
| if (rc) |
| dbFree(ip, xaddr, xlen); |
| else |
| DT_PUTPAGE(rmp); |
| |
| DT_PUTPAGE(smp); |
| |
| if (!DO_INDEX(ip)) |
| ip->i_size = xlen << sbi->l2bsize; |
| |
| 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; |
| |
| /* Allocate blocks to quota. */ |
| rc = dquot_alloc_block(ip, n); |
| if (rc) |
| goto extendOut; |
| quota_allocation += n; |
| |
| 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); |
| } |
| } else if (!DO_INDEX(ip)) |
| ip->i_size = lengthPXD(pxd) << sbi->l2bsize; |
| |
| |
| 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; |
| } |
| |
| if (!DO_INDEX(ip)) |
| ip->i_size += PSIZE; |
| |
| /* |
| * 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 */ |
| rc = ciGetLeafPrefixKey(lp, |
| lp->header.nextindex-1, |
| rp, 0, &key, |
| sbi->mntflag); |
| if (rc) { |
| DT_PUTPAGE(lmp); |
| DT_PUTPAGE(rmp); |
| DT_PUTPAGE(smp); |
| goto splitOut; |
| } |
| } 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: |
| jfs_err("dtSplitUp(): UFO!"); |
| 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); |
| |
| /* Rollback quota allocation */ |
| if (rc && quota_allocation) |
| dquot_free_block(ip, quota_allocation); |
| |
| 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) |
| { |
| 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; |
| |
| /* Allocate blocks to quota. */ |
| rc = dquot_alloc_block(ip, lengthPXD(pxd)); |
| if (rc) { |
| release_metapage(rmp); |
| return rc; |
| } |
| |
| jfs_info("dtSplitPage: ip:0x%p smp:0x%p rmp:0x%p", 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) { |
| discard_metapage(rmp); |
| return rc; |
| } |
| |
| BT_MARK_DIRTY(mp, ip); |
| /* |
| * acquire a transaction lock on the next page |
| */ |
| tlck = txLock(tid, ip, mp, tlckDTREE | tlckRELINK); |
| jfs_info("dtSplitPage: tlck = 0x%p, ip = 0x%p, mp=0x%p", |
| 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)) { |
| s64 lblock; |
| |
| mp = NULL; |
| 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, &lblock); |
| } |
| 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; |
| |
| return rc; |
| } |
| |
| |
| /* |
| * 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)) { |
| s64 lblock; |
| |
| mp = NULL; |
| 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, &lblock); |
| } |
| if (mp) |
| release_metapage(mp); |
| } |
| } |
| |
| /* |
| * extend the page |
| */ |
| sp->header.self = *pxd; |
| |
| jfs_info("dtExtendPage: ip:0x%p smp:0x%p sp:0x%p", 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; |
| |
| /* |
| * 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; |
| |
| 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; |
| int rc; |
| |
| /* 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); |
| if (!rmp) |
| return -EIO; |
| |
| rp = rmp->data; |
| |
| /* Allocate blocks to quota. */ |
| rc = dquot_alloc_block(ip, lengthPXD(pxd)); |
| if (rc) { |
| release_metapage(rmp); |
| return rc; |
| } |
| |
| 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)) { |
| s64 lblock; |
| struct metapage *mp = NULL; |
| 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, &lblock); |
| } |
| 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; |
| |
| 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) { |
| s64 lblock; |
| |
| imp = NULL; |
| 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, &lblock); |
| } |
| 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))) { |
| BT_PUTPAGE(fmp); |
| return rc; |
| } |
| |
| xlen = lengthPXD(&fp->header.self); |
| |
| /* Free quota allocation. */ |
| dquot_free_block(ip, 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))) { |
| DT_PUTPAGE(mp); |
| return rc; |
| } |
| |
| xlen = lengthPXD(&p->header.self); |
| |
| /* Free quota allocation */ |
| dquot_free_block(ip, 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; |
| } |
| |
| if (!DO_INDEX(ip)) |
| ip->i_size -= PSIZE; |
| |
| return 0; |
| } |
| |
| #ifdef _NOTYET |
| /* |
| * 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); |
| |
| jfs_info("dtRelocate: lmxaddr:%Ld xaddr:%Ld:%Ld xlen:%d", |
| (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); |
| jfs_info("dtRelocate: parent router entry validated."); |
| |
| /* |
| * 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; |
| |
| /* unpin the relocated page */ |
| DT_PUTPAGE(mp); |
| jfs_info("dtRelocate: target dtpage relocated."); |
| |
| /* 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; |
| */ |
| jfs_info("dtRelocate: update parent router entry."); |
| 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) { |
| DT_PUTPAGE(mp); |
| 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; |
| } |
| #endif /* _NOTYET */ |
| |
| /* |
| * 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); |
| jfs_info("dtRelink nextbn: tlck = 0x%p, ip = 0x%p, mp=0x%p", |
| 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); |
| jfs_info("dtRelink prevbn: tlck = 0x%p, ip = 0x%p, mp=0x%p", |
| 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_dirtable_inline(ip)) { |
| 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; |
| } 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); |
| |
| 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); |
| if (BT_IS_ROOT(mp)) |
| tlck->type |= tlckBTROOT; |
| |
| 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[dtlck->index]; |
| 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 |
| */ |
| static 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_path.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; |
| 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; |
| |
| 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) { |
| jfs_err("jfs_readdir detected " |
| "infinite loop!"); |
| 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) { |
| jfs_err("jfs_readdir: bad index table"); |
| 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 |
| */ |
| 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 { |
| jfs_err("jfs_readdir called with " |
| "invalid offset!"); |
| } |
| 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))) { |
| jfs_err("jfs_readdir: unexpected rc = %d " |
| "from dtReadNext", 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); |
| jfs_warn("jfs_readdir: __get_free_page failed!"); |
| 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 *) |