/* * Copyright (C) International Business Machines Corp., 2000-2005 * * 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_xtree.c: extent allocation descriptor B+-tree manager */ #include <linux/fs.h> #include <linux/module.h> #include <linux/quotaops.h> #include <linux/seq_file.h> #include "jfs_incore.h" #include "jfs_filsys.h" #include "jfs_metapage.h" #include "jfs_dmap.h" #include "jfs_dinode.h" #include "jfs_superblock.h" #include "jfs_debug.h" /* * xtree local flag */ #define XT_INSERT 0x00000001 /* * xtree key/entry comparison: extent offset * * return: * -1: k < start of extent * 0: start_of_extent <= k <= end_of_extent * 1: k > end_of_extent */ #define XT_CMP(CMP, K, X, OFFSET64)\ {\ OFFSET64 = offsetXAD(X);\ (CMP) = ((K) >= OFFSET64 + lengthXAD(X)) ? 1 :\ ((K) < OFFSET64) ? -1 : 0;\ } /* write a xad entry */ #define XT_PUTENTRY(XAD, FLAG, OFF, LEN, ADDR)\ {\ (XAD)->flag = (FLAG);\ XADoffset((XAD), (OFF));\ XADlength((XAD), (LEN));\ XADaddress((XAD), (ADDR));\ } #define XT_PAGE(IP, MP) BT_PAGE(IP, MP, xtpage_t, i_xtroot) /* get page buffer for specified block address */ /* ToDo: Replace this ugly macro with a function */ #define XT_GETPAGE(IP, BN, MP, SIZE, P, RC)\ {\ BT_GETPAGE(IP, BN, MP, xtpage_t, SIZE, P, RC, i_xtroot)\ if (!(RC))\ {\ if ((le16_to_cpu((P)->header.nextindex) < XTENTRYSTART) ||\ (le16_to_cpu((P)->header.nextindex) > le16_to_cpu((P)->header.maxentry)) ||\ (le16_to_cpu((P)->header.maxentry) > (((BN)==0)?XTROOTMAXSLOT:PSIZE>>L2XTSLOTSIZE)))\ {\ jfs_error((IP)->i_sb, "XT_GETPAGE: xtree page corrupt");\ BT_PUTPAGE(MP);\ MP = NULL;\ RC = -EIO;\ }\ }\ } /* for consistency */ #define XT_PUTPAGE(MP) BT_PUTPAGE(MP) #define XT_GETSEARCH(IP, LEAF, BN, MP, P, INDEX) \ BT_GETSEARCH(IP, LEAF, BN, MP, xtpage_t, P, INDEX, i_xtroot) /* xtree entry parameter descriptor */ struct xtsplit { struct metapage *mp; s16 index; u8 flag; s64 off; s64 addr; int len; struct pxdlist *pxdlist; }; /* * statistics */ #ifdef CONFIG_JFS_STATISTICS static struct { uint search; uint fastSearch; uint split; } xtStat; #endif /* * forward references */ static int xtSearch(struct inode *ip, s64 xoff, s64 *next, int *cmpp, struct btstack * btstack, int flag); static int xtSplitUp(tid_t tid, struct inode *ip, struct xtsplit * split, struct btstack * btstack); static int xtSplitPage(tid_t tid, struct inode *ip, struct xtsplit * split, struct metapage ** rmpp, s64 * rbnp); static int xtSplitRoot(tid_t tid, struct inode *ip, struct xtsplit * split, struct metapage ** rmpp); #ifdef _STILL_TO_PORT static int xtDeleteUp(tid_t tid, struct inode *ip, struct metapage * fmp, xtpage_t * fp, struct btstack * btstack); static int xtSearchNode(struct inode *ip, xad_t * xad, int *cmpp, struct btstack * btstack, int flag); static int xtRelink(tid_t tid, struct inode *ip, xtpage_t * fp); #endif /* _STILL_TO_PORT */ /* * xtLookup() * * function: map a single page into a physical extent; */ int xtLookup(struct inode *ip, s64 lstart, s64 llen, int *pflag, s64 * paddr, s32 * plen, int no_check) { int rc = 0; struct btstack btstack; int cmp; s64 bn; struct metapage *mp; xtpage_t *p; int index; xad_t *xad; s64 next, size, xoff, xend; int xlen; s64 xaddr; *paddr = 0; *plen = llen; if (!no_check) { /* is lookup offset beyond eof ? */ size = ((u64) ip->i_size + (JFS_SBI(ip->i_sb)->bsize - 1)) >> JFS_SBI(ip->i_sb)->l2bsize; if (lstart >= size) return 0; } /* * search for the xad entry covering the logical extent */ //search: if ((rc = xtSearch(ip, lstart, &next, &cmp, &btstack, 0))) { jfs_err("xtLookup: xtSearch returned %d", rc); return rc; } /* * compute the physical extent covering logical extent * * N.B. search may have failed (e.g., hole in sparse file), * and returned the index of the next entry. */ /* retrieve search result */ XT_GETSEARCH(ip, btstack.top, bn, mp, p, index); /* is xad found covering start of logical extent ? * lstart is a page start address, * i.e., lstart cannot start in a hole; */ if (cmp) { if (next) *plen = min(next - lstart, llen); goto out; } /* * lxd covered by xad */ xad = &p->xad[index]; xoff = offsetXAD(xad); xlen = lengthXAD(xad); xend = xoff + xlen; xaddr = addressXAD(xad); /* initialize new pxd */ *pflag = xad->flag; *paddr = xaddr + (lstart - xoff); /* a page must be fully covered by an xad */ *plen = min(xend - lstart, llen); out: XT_PUTPAGE(mp); return rc; } /* * xtSearch() * * function: search for the xad entry covering specified offset. * * parameters: * ip - file object; * xoff - extent offset; * nextp - address of next extent (if any) for search miss * cmpp - comparison result: * btstack - traverse stack; * flag - search process flag (XT_INSERT); * * returns: * btstack contains (bn, index) of search path traversed to the entry. * *cmpp is set to result of comparison with the entry returned. * the page containing the entry is pinned at exit. */ static int xtSearch(struct inode *ip, s64 xoff, s64 *nextp, int *cmpp, struct btstack * btstack, int flag) { struct jfs_inode_info *jfs_ip = JFS_IP(ip); int rc = 0; int cmp = 1; /* init for empty page */ s64 bn; /* block number */ struct metapage *mp; /* page buffer */ xtpage_t *p; /* page */ xad_t *xad; int base, index, lim, btindex; struct btframe *btsp; int nsplit = 0; /* number of pages to split */ s64 t64; s64 next = 0; INCREMENT(xtStat.search); BT_CLR(btstack); btstack->nsplit = 0; /* * 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 */ XT_GETPAGE(ip, bn, mp, PSIZE, p, rc); if (rc) return rc; /* try sequential access heuristics with the previous * access entry in target leaf page: * once search narrowed down into the target leaf, * key must either match an entry in the leaf or * key entry does not exist in the tree; */ //fastSearch: if ((jfs_ip->btorder & BT_SEQUENTIAL) && (p->header.flag & BT_LEAF) && (index = jfs_ip->btindex) < le16_to_cpu(p->header.nextindex)) { xad = &p->xad[index]; t64 = offsetXAD(xad); if (xoff < t64 + lengthXAD(xad)) { if (xoff >= t64) { *cmpp = 0; goto out; } /* stop sequential access heuristics */ goto binarySearch; } else { /* (t64 + lengthXAD(xad)) <= xoff */ /* try next sequential entry */ index++; if (index < le16_to_cpu(p->header.nextindex)) { xad++; t64 = offsetXAD(xad); if (xoff < t64 + lengthXAD(xad)) { if (xoff >= t64) { *cmpp = 0; goto out; } /* miss: key falls between * previous and this entry */ *cmpp = 1; next = t64; goto out; } /* (xoff >= t64 + lengthXAD(xad)); * matching entry may be further out: * stop heuristic search */ /* stop sequential access heuristics */ goto binarySearch; } /* (index == p->header.nextindex); * miss: key entry does not exist in * the target leaf/tree */ *cmpp = 1; goto out; } /* * if hit, return index of the entry found, and * if miss, where new entry with search key is * to be inserted; */ out: /* compute number of pages to split */ if (flag & XT_INSERT) { if (p->header.nextindex == /* little-endian */ p->header.maxentry) nsplit++; else nsplit = 0; btstack->nsplit = nsplit; } /* save search result */ btsp = btstack->top; btsp->bn = bn; btsp->index = index; btsp->mp = mp; /* update sequential access heuristics */ jfs_ip->btindex = index; if (nextp) *nextp = next; INCREMENT(xtStat.fastSearch); return 0; } /* well, ... full search now */ binarySearch: lim = le16_to_cpu(p->header.nextindex) - XTENTRYSTART; /* * binary search with search key K on the current page */ for (base = XTENTRYSTART; lim; lim >>= 1) { index = base + (lim >> 1); XT_CMP(cmp, xoff, &p->xad[index], t64); if (cmp == 0) { /* * search hit */ /* search hit - leaf page: * return the entry found */ if (p->header.flag & BT_LEAF) { *cmpp = cmp; /* compute number of pages to split */ if (flag & XT_INSERT) { if (p->header.nextindex == p->header.maxentry) nsplit++; else nsplit = 0; btstack->nsplit = nsplit; } /* save search result */ btsp = btstack->top; btsp->bn = bn; btsp->index = index; btsp->mp = mp; /* init sequential access heuristics */ btindex = jfs_ip->btindex; if (index == btindex || index == btindex + 1) jfs_ip->btorder = BT_SEQUENTIAL; else jfs_ip->btorder = BT_RANDOM; jfs_ip->btindex = index; return 0; } /* search hit - internal page: * descend/search its child page */ if (index < le16_to_cpu(p->header.nextindex)-1) next = offsetXAD(&p->xad[index + 1]); goto next; } 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 maxentry index. */ if (base < le16_to_cpu(p->header.nextindex)) next = offsetXAD(&p->xad[base]); /* * 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) { *cmpp = cmp; /* compute number of pages to split */ if (flag & XT_INSERT) { if (p->header.nextindex == p->header.maxentry) nsplit++; else nsplit = 0; btstack->nsplit = nsplit; } /* save search result */ btsp = btstack->top; btsp->bn = bn; btsp->index = base; btsp->mp = mp; /* init sequential access heuristics */ btindex = jfs_ip->btindex; if (base == btindex || base == btindex + 1) jfs_ip->btorder = BT_SEQUENTIAL; else jfs_ip->btorder = BT_RANDOM; jfs_ip->btindex = base; if (nextp) *nextp = next; return 0; } /* * search miss - non-leaf 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 */ next: /* update number of pages to split */ if (p->header.nextindex == p->header.maxentry) nsplit++; else nsplit = 0; /* push (bn, index) of the parent page/entry */ if (BT_STACK_FULL(btstack)) { jfs_error(ip->i_sb, "stack overrun in xtSearch!"); XT_PUTPAGE(mp); return -EIO; } BT_PUSH(btstack, bn, index); /* get the child page block number */ bn = addressXAD(&p->xad[index]); /* unpin the parent page */ XT_PUTPAGE(mp); } } /* * xtInsert() * * function: * * parameter: * tid - transaction id; * ip - file object; * xflag - extent flag (XAD_NOTRECORDED): * xoff - extent offset; * xlen - extent length; * xaddrp - extent address pointer (in/out): * if (*xaddrp) * caller allocated data extent at *xaddrp; * else * allocate data extent and return its xaddr; * flag - * * return: */ int xtInsert(tid_t tid, /* transaction id */ struct inode *ip, int xflag, s64 xoff, s32 xlen, s64 * xaddrp, int flag) { int rc = 0; s64 xaddr, hint; struct metapage *mp; /* meta-page buffer */ xtpage_t *p; /* base B+-tree index page */ s64 bn; int index, nextindex; struct btstack btstack; /* traverse stack */ struct xtsplit split; /* split information */ xad_t *xad; int cmp; s64 next; struct tlock *tlck; struct xtlock *xtlck; jfs_info("xtInsert: nxoff:0x%lx nxlen:0x%x", (ulong) xoff, xlen); /* * search for the entry location at which to insert: * * xtFastSearch() and xtSearch() both returns (leaf page * pinned, index at which to insert). * n.b. xtSearch() may return index of maxentry of * the full page. */ if ((rc = xtSearch(ip, xoff, &next, &cmp, &btstack, XT_INSERT))) return rc; /* retrieve search result */ XT_GETSEARCH(ip, btstack.top, bn, mp, p, index); /* This test must follow XT_GETSEARCH since mp must be valid if * we branch to out: */ if ((cmp == 0) || (next && (xlen > next - xoff))) { rc = -EEXIST; goto out; } /* * allocate data extent requested * * allocation hint: last xad */ if ((xaddr = *xaddrp) == 0) { if (index > XTENTRYSTART) { xad = &p->xad[index - 1]; hint = addressXAD(xad) + lengthXAD(xad) - 1; } else hint = 0; if ((rc = vfs_dq_alloc_block(ip, xlen))) goto out; if ((rc = dbAlloc(ip, hint, (s64) xlen, &xaddr))) { vfs_dq_free_block(ip, xlen); goto out; } } /* * insert entry for new extent */ xflag |= XAD_NEW; /* * if the leaf page is full, split the page and * propagate up the router entry for the new page from split * * The xtSplitUp() will insert the entry and unpin the leaf page. */ nextindex = le16_to_cpu(p->header.nextindex); if (nextindex == le16_to_cpu(p->header.maxentry)) { split.mp = mp; split.index = index; split.flag = xflag; split.off = xoff; split.len = xlen; split.addr = xaddr; split.pxdlist = NULL; if ((rc = xtSplitUp(tid, ip, &split, &btstack))) { /* undo data extent allocation */ if (*xaddrp == 0) { dbFree(ip, xaddr, (s64) xlen); vfs_dq_free_block(ip, xlen); } return rc; } *xaddrp = xaddr; return 0; } /* * insert the new entry into the leaf page */ /* * acquire a transaction lock on the leaf page; * * action: xad insertion/extension; */ BT_MARK_DIRTY(mp, ip); /* if insert into middle, shift right remaining entries. */ if (index < nextindex) memmove(&p->xad[index + 1], &p->xad[index], (nextindex - index) * sizeof(xad_t)); /* insert the new entry: mark the entry NEW */ xad = &p->xad[index]; XT_PUTENTRY(xad, xflag, xoff, xlen, xaddr); /* advance next available entry index */ le16_add_cpu(&p->header.nextindex, 1); /* Don't log it if there are no links to the file */ if (!test_cflag(COMMIT_Nolink, ip)) { tlck = txLock(tid, ip, mp, tlckXTREE | tlckGROW); xtlck = (struct xtlock *) & tlck->lock; xtlck->lwm.offset = (xtlck->lwm.offset) ? min(index, (int)xtlck->lwm.offset) : index; xtlck->lwm.length = le16_to_cpu(p->header.nextindex) - xtlck->lwm.offset; } *xaddrp = xaddr; out: /* unpin the leaf page */ XT_PUTPAGE(mp); return rc; } /* * xtSplitUp() * * function: * split full pages as propagating insertion up the tree * * parameter: * tid - transaction id; * ip - file object; * split - entry parameter descriptor; * btstack - traverse stack from xtSearch() * * return: */ static int xtSplitUp(tid_t tid, struct inode *ip, struct xtsplit * split, struct btstack * btstack) { int rc = 0; struct metapage *smp; xtpage_t *sp; /* split page */ struct metapage *rmp; s64 rbn; /* new right page block number */ struct metapage *rcmp; xtpage_t *rcp; /* right child page */ s64 rcbn; /* right child page block number */ int skip; /* index of entry of insertion */ int nextindex; /* next available entry index of p */ struct btframe *parent; /* parent page entry on traverse stack */ xad_t *xad; s64 xaddr; int xlen; int nsplit; /* number of pages split */ struct pxdlist pxdlist; pxd_t *pxd; struct tlock *tlck; struct xtlock *xtlck; smp = split->mp; sp = XT_PAGE(ip, smp); /* is inode xtree root extension/inline EA area free ? */ if ((sp->header.flag & BT_ROOT) && (!S_ISDIR(ip->i_mode)) && (le16_to_cpu(sp->header.maxentry) < XTROOTMAXSLOT) && (JFS_IP(ip)->mode2 & INLINEEA)) { sp->header.maxentry = cpu_to_le16(XTROOTMAXSLOT); JFS_IP(ip)->mode2 &= ~INLINEEA; BT_MARK_DIRTY(smp, ip); /* * acquire a transaction lock on the leaf page; * * action: xad insertion/extension; */ /* if insert into middle, shift right remaining entries. */ skip = split->index; nextindex = le16_to_cpu(sp->header.nextindex); if (skip < nextindex) memmove(&sp->xad[skip + 1], &sp->xad[skip], (nextindex - skip) * sizeof(xad_t)); /* insert the new entry: mark the entry NEW */ xad = &sp->xad[skip]; XT_PUTENTRY(xad, split->flag, split->off, split->len, split->addr); /* advance next available entry index */ le16_add_cpu(&sp->header.nextindex, 1); /* Don't log it if there are no links to the file */ if (!test_cflag(COMMIT_Nolink, ip)) { tlck = txLock(tid, ip, smp, tlckXTREE | tlckGROW); xtlck = (struct xtlock *) & tlck->lock; xtlck->lwm.offset = (xtlck->lwm.offset) ? min(skip, (int)xtlck->lwm.offset) : skip; xtlck->lwm.length = le16_to_cpu(sp->header.nextindex) - xtlck->lwm.offset; } return 0; } /* * allocate new index blocks to cover index page split(s) * * allocation hint: ? */ if (split->pxdlist == NULL) { nsplit = btstack->nsplit; split->pxdlist = &pxdlist; pxdlist.maxnpxd = pxdlist.npxd = 0; pxd = &pxdlist.pxd[0]; xlen = JFS_SBI(ip->i_sb)->nbperpage; for (; nsplit > 0; nsplit--, pxd++) { if ((rc = dbAlloc(ip, (s64) 0, (s64) xlen, &xaddr)) == 0) { PXDaddress(pxd, xaddr); PXDlength(pxd, xlen); pxdlist.maxnpxd++; continue; } /* undo allocation */ XT_PUTPAGE(smp); return rc; } } /* * Split leaf page <sp> into <sp> and a new right page <rp>. * * The split routines insert the new entry into the leaf page, * and acquire txLock as appropriate. * return <rp> pinned and its block number <rpbn>. */ rc = (sp->header.flag & BT_ROOT) ? xtSplitRoot(tid, ip, split, &rmp) : xtSplitPage(tid, ip, split, &rmp, &rbn); XT_PUTPAGE(smp); if (rc) return -EIO; /* * 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 3 pages pinned at any time: * right child, left parent and right parent (when the parent splits) * to keep the child page 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 <rcp> pinned */ rcmp = rmp; rcbn = rbn; rcp = XT_PAGE(ip, rcmp); /* * insert router entry in parent for new right child page <rp> */ /* get/pin the parent page <sp> */ XT_GETPAGE(ip, parent->bn, smp, PSIZE, sp, rc); if (rc) { XT_PUTPAGE(rcmp); return rc; } /* * The new key entry goes ONE AFTER the index of parent entry, * because the split was to the right. */ skip = parent->index + 1; /* * split or shift right remaining entries of the parent page */ nextindex = le16_to_cpu(sp->header.nextindex); /* * parent page is full - split the parent page */ if (nextindex == le16_to_cpu(sp->header.maxentry)) { /* init for parent page split */ split->mp = smp; split->index = skip; /* index at insert */ split->flag = XAD_NEW; split->off = offsetXAD(&rcp->xad[XTENTRYSTART]); split->len = JFS_SBI(ip->i_sb)->nbperpage; split->addr = rcbn; /* unpin previous right child page */ XT_PUTPAGE(rcmp); /* The split routines insert the new entry, * and acquire txLock as appropriate. * return <rp> pinned and its block number <rpbn>. */ rc = (sp->header.flag & BT_ROOT) ? xtSplitRoot(tid, ip, split, &rmp) : xtSplitPage(tid, ip, split, &rmp, &rbn); if (rc) { XT_PUTPAGE(smp); return rc; } XT_PUTPAGE(smp); /* keep new child page <rp> pinned */ } /* * parent page is not full - insert in parent page */ else { /* * insert router entry in parent for the right child * page from the first entry of the right child page: */ /* * acquire a transaction lock on the parent page; * * action: router xad insertion; */ BT_MARK_DIRTY(smp, ip); /* * if insert into middle, shift right remaining entries */ if (skip < nextindex) memmove(&sp->xad[skip + 1], &sp->xad[skip], (nextindex - skip) << L2XTSLOTSIZE); /* insert the router entry */ xad = &sp->xad[skip]; XT_PUTENTRY(xad, XAD_NEW, offsetXAD(&rcp->xad[XTENTRYSTART]), JFS_SBI(ip->i_sb)->nbperpage, rcbn); /* advance next available entry index. */ le16_add_cpu(&sp->header.nextindex, 1); /* Don't log it if there are no links to the file */ if (!test_cflag(COMMIT_Nolink, ip)) { tlck = txLock(tid, ip, smp, tlckXTREE | tlckGROW); xtlck = (struct xtlock *) & tlck->lock; xtlck->lwm.offset = (xtlck->lwm.offset) ? min(skip, (int)xtlck->lwm.offset) : skip; xtlck->lwm.length = le16_to_cpu(sp->header.nextindex) - xtlck->lwm.offset; } /* unpin parent page */ XT_PUTPAGE(smp); /* exit propagate up */ break; } } /* unpin current right page */ XT_PUTPAGE(rmp); return 0; } /* * xtSplitPage() * * function: * split a full non-root page into * original/split/left page and new right page * i.e., the original/split page remains as left page. * * parameter: * int tid, * struct inode *ip, * struct xtsplit *split, * struct metapage **rmpp, * u64 *rbnp, * * return: * Pointer to page in which to insert or NULL on error. */ static int xtSplitPage(tid_t tid, struct inode *ip, struct xtsplit * split, struct metapage ** rmpp, s64 * rbnp) { int rc = 0; struct metapage *smp; xtpage_t *sp; struct metapage *rmp; xtpage_t *rp; /* new right page allocated */ s64 rbn; /* new right page block number */ struct metapage *mp; xtpage_t *p; s64 nextbn; int skip, maxentry, middle, righthalf, n; xad_t *xad; struct pxdlist *pxdlist; pxd_t *pxd; struct tlock *tlck; struct xtlock *sxtlck = NULL, *rxtlck = NULL; int quota_allocation = 0; smp = split->mp; sp = XT_PAGE(ip, smp); INCREMENT(xtStat.split); pxdlist = split->pxdlist; pxd = &pxdlist->pxd[pxdlist->npxd]; pxdlist->npxd++; rbn = addressPXD(pxd); /* Allocate blocks to quota. */ if (vfs_dq_alloc_block(ip, lengthPXD(pxd))) { rc = -EDQUOT; goto clean_up; } quota_allocation += lengthPXD(pxd); /* * allocate the new right page for the split */ rmp = get_metapage(ip, rbn, PSIZE, 1); if (rmp == NULL) { rc = -EIO; goto clean_up; } jfs_info("xtSplitPage: ip:0x%p smp:0x%p rmp:0x%p", ip, smp, rmp); BT_MARK_DIRTY(rmp, ip); /* * action: new page; */ rp = (xtpage_t *) rmp->data; rp->header.self = *pxd; rp->header.flag = sp->header.flag & BT_TYPE; rp->header.maxentry = sp->header.maxentry; /* little-endian */ rp->header.nextindex = cpu_to_le16(XTENTRYSTART); BT_MARK_DIRTY(smp, ip); /* Don't log it if there are no links to the file */ if (!test_cflag(COMMIT_Nolink, ip)) { /* * acquire a transaction lock on the new right page; */ tlck = txLock(tid, ip, rmp, tlckXTREE | tlckNEW); rxtlck = (struct xtlock *) & tlck->lock; rxtlck->lwm.offset = XTENTRYSTART; /* * acquire a transaction lock on the split page */ tlck = txLock(tid, ip, smp, tlckXTREE | tlckGROW); sxtlck = (struct xtlock *) & tlck->lock; } /* * initialize/update sibling pointers of <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); skip = split->index; /* * sequential append at tail (after last entry of last page) * * 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 will 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 && skip == le16_to_cpu(sp->header.maxentry)) { /* * acquire a transaction lock on the new/right page; * * action: xad insertion; */ /* insert entry at the first entry of the new right page */ xad = &rp->xad[XTENTRYSTART]; XT_PUTENTRY(xad, split->flag, split->off, split->len, split->addr); rp->header.nextindex = cpu_to_le16(XTENTRYSTART + 1); if (!test_cflag(COMMIT_Nolink, ip)) { /* rxtlck->lwm.offset = XTENTRYSTART; */ rxtlck->lwm.length = 1; } *rmpp = rmp; *rbnp = rbn; jfs_info("xtSplitPage: sp:0x%p rp:0x%p", sp, rp); return 0; } /* * non-sequential insert (at possibly middle page) */ /* * update previous pointer of old next/right page of <sp> */ if (nextbn != 0) { XT_GETPAGE(ip, nextbn, mp, PSIZE, p, rc); if (rc) { XT_PUTPAGE(rmp); goto clean_up; } BT_MARK_DIRTY(mp, ip); /* * acquire a transaction lock on the next page; * * action:sibling pointer update; */ if (!test_cflag(COMMIT_Nolink, ip)) tlck = txLock(tid, ip, mp, tlckXTREE | tlckRELINK); p->header.prev = cpu_to_le64(rbn); /* sibling page may have been updated previously, or * it may be updated later; */ XT_PUTPAGE(mp); } /* * split the data between the split and new/right pages */ maxentry = le16_to_cpu(sp->header.maxentry); middle = maxentry >> 1; righthalf = maxentry - middle; /* * skip index in old split/left page - insert into left page: */ if (skip <= middle) { /* move right half of split page to the new right page */ memmove(&rp->xad[XTENTRYSTART], &sp->xad[middle], righthalf << L2XTSLOTSIZE); /* shift right tail of left half to make room for new entry */ if (skip < middle) memmove(&sp->xad[skip + 1], &sp->xad[skip], (middle - skip) << L2XTSLOTSIZE); /* insert new entry */ xad = &sp->xad[skip]; XT_PUTENTRY(xad, split->flag, split->off, split->len, split->addr); /* update page header */ sp->header.nextindex = cpu_to_le16(middle + 1); if (!test_cflag(COMMIT_Nolink, ip)) { sxtlck->lwm.offset = (sxtlck->lwm.offset) ? min(skip, (int)sxtlck->lwm.offset) : skip; } rp->header.nextindex = cpu_to_le16(XTENTRYSTART + righthalf); } /* * skip index in new right page - insert into right page: */ else { /* move left head of right half to right page */ n = skip - middle; memmove(&rp->xad[XTENTRYSTART], &sp->xad[middle], n << L2XTSLOTSIZE); /* insert new entry */ n += XTENTRYSTART; xad = &rp->xad[n]; XT_PUTENTRY(xad, split->flag, split->off, split->len, split->addr); /* move right tail of right half to right page */ if (skip < maxentry) memmove(&rp->xad[n + 1], &sp->xad[skip], (maxentry - skip) << L2XTSLOTSIZE); /* update page header */ sp->header.nextindex = cpu_to_le16(middle); if (!test_cflag(COMMIT_Nolink, ip)) { sxtlck->lwm.offset = (sxtlck->lwm.offset) ? min(middle, (int)sxtlck->lwm.offset) : middle; } rp->header.nextindex = cpu_to_le16(XTENTRYSTART + righthalf + 1); } if (!test_cflag(COMMIT_Nolink, ip)) { sxtlck->lwm.length = le16_to_cpu(sp->header.nextindex) - sxtlck->lwm.offset; /* rxtlck->lwm.offset = XTENTRYSTART; */ rxtlck->lwm.length = le16_to_cpu(rp->header.nextindex) - XTENTRYSTART; } *rmpp = rmp; *rbnp = rbn; jfs_info("xtSplitPage: sp:0x%p rp:0x%p", sp, rp); return rc; clean_up: /* Rollback quota allocation. */ if (quota_allocation) vfs_dq_free_block(ip, quota_allocation); return (rc); } /* * xtSplitRoot() * * 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: * int tid, * struct inode *ip, * struct xtsplit *split, * struct metapage **rmpp) * * return: * Pointer to page in which to insert or NULL on error. */ static int xtSplitRoot(tid_t tid, struct inode *ip, struct xtsplit * split, struct metapage ** rmpp) { xtpage_t *sp; struct metapage *rmp; xtpage_t *rp; s64 rbn; int skip, nextindex; xad_t *xad; pxd_t *pxd; struct pxdlist *pxdlist; struct tlock *tlck; struct xtlock *xtlck; sp = &JFS_IP(ip)->i_xtroot; INCREMENT(xtStat.split); /* * allocate a single (right) child page */ 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. */ if (vfs_dq_alloc_block(ip, lengthPXD(pxd))) { release_metapage(rmp); return -EDQUOT; } jfs_info("xtSplitRoot: ip:0x%p rmp:0x%p", ip, rmp); /* * acquire a transaction lock on the new right page; * * action: new page; */ BT_MARK_DIRTY(rmp, ip); rp = (xtpage_t *) rmp->data; rp->header.flag = (sp->header.flag & BT_LEAF) ? BT_LEAF : BT_INTERNAL; rp->header.self = *pxd; rp->header.nextindex = cpu_to_le16(XTENTRYSTART); rp->header.maxentry = cpu_to_le16(PSIZE >> L2XTSLOTSIZE); /* initialize sibling pointers */ rp->header.next = 0; rp->header.prev = 0; /* * copy the in-line root page into new right page extent */ nextindex = le16_to_cpu(sp->header.maxentry); memmove(&rp->xad[XTENTRYSTART], &sp->xad[XTENTRYSTART], (nextindex - XTENTRYSTART) << L2XTSLOTSIZE); /* * insert the new entry into the new right/child page * (skip index in the new right page will not change) */ skip = split->index; /* if insert into middle, shift right remaining entries */ if (skip != nextindex) memmove(&rp->xad[skip + 1], &rp->xad[skip], (nextindex - skip) * sizeof(xad_t)); xad = &rp->xad[skip]; XT_PUTENTRY(xad, split->flag, split->off, split->len, split->addr); /* update page header */ rp->header.nextindex = cpu_to_le16(nextindex + 1); if (!test_cflag(COMMIT_Nolink, ip)) { tlck = txLock(tid, ip, rmp, tlckXTREE | tlckNEW); xtlck = (struct xtlock *) & tlck->lock; xtlck->lwm.offset = XTENTRYSTART; xtlck->lwm.length = le16_to_cpu(rp->header.nextindex) - XTENTRYSTART; } /* * reset the root * * init root with the single entry for the new right 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. */ /* * acquire a transaction lock on the root page (in-memory inode); * * action: root split; */ BT_MARK_DIRTY(split->mp, ip); xad = &sp->xad[XTENTRYSTART]; XT_PUTENTRY(xad, XAD_NEW, 0, JFS_SBI(ip->i_sb)->nbperpage, rbn); /* update page header of root */ sp->header.flag &= ~BT_LEAF; sp->header.flag |= BT_INTERNAL; sp->header.nextindex = cpu_to_le16(XTENTRYSTART + 1); if (!test_cflag(COMMIT_Nolink, ip)) { tlck = txLock(tid, ip, split->mp, tlckXTREE | tlckGROW); xtlck = (struct xtlock *) & tlck->lock; xtlck->lwm.offset = XTENTRYSTART; xtlck->lwm.length = 1; } *rmpp = rmp; jfs_info("xtSplitRoot: sp:0x%p rp:0x%p", sp, rp); return 0; } /* * xtExtend() * * function: extend in-place; * * note: existing extent may or may not have been committed. * caller is responsible for pager buffer cache update, and * working block allocation map update; * update pmap: alloc whole extended extent; */ int xtExtend(tid_t tid, /* transaction id */ struct inode *ip, s64 xoff, /* delta extent offset */ s32 xlen, /* delta extent length */ int flag) { int rc = 0; int cmp; struct metapage *mp; /* meta-page buffer */ xtpage_t *p; /* base B+-tree index page */ s64 bn; int index, nextindex, len; struct btstack btstack; /* traverse stack */ struct xtsplit split; /* split information */ xad_t *xad; s64 xaddr; struct tlock *tlck; struct xtlock *xtlck = NULL; jfs_info("xtExtend: nxoff:0x%lx nxlen:0x%x", (ulong) xoff, xlen); /* there must exist extent to be extended */ if ((rc = xtSearch(ip, xoff - 1, NULL, &cmp, &btstack, XT_INSERT))) return rc; /* retrieve search result */ XT_GETSEARCH(ip, btstack.top, bn, mp, p, index); if (cmp != 0) { XT_PUTPAGE(mp); jfs_error(ip->i_sb, "xtExtend: xtSearch did not find extent"); return -EIO; } /* extension must be contiguous */ xad = &p->xad[index]; if ((offsetXAD(xad) + lengthXAD(xad)) != xoff) { XT_PUTPAGE(mp); jfs_error(ip->i_sb, "xtExtend: extension is not contiguous"); return -EIO; } /* * acquire a transaction lock on the leaf page; * * action: xad insertion/extension; */ BT_MARK_DIRTY(mp, ip); if (!test_cflag(COMMIT_Nolink, ip)) { tlck = txLock(tid, ip, mp, tlckXTREE | tlckGROW); xtlck = (struct xtlock *) & tlck->lock; } /* extend will overflow extent ? */ xlen = lengthXAD(xad) + xlen; if ((len = xlen - MAXXLEN) <= 0) goto extendOld; /* * extent overflow: insert entry for new extent */ //insertNew: xoff = offsetXAD(xad) + MAXXLEN; xaddr = addressXAD(xad) + MAXXLEN; nextindex = le16_to_cpu(p->header.nextindex); /* * if the leaf page is full, insert the new entry and * propagate up the router entry for the new page from split * * The xtSplitUp() will insert the entry and unpin the leaf page. */ if (nextindex == le16_to_cpu(p->header.maxentry)) { /* xtSpliUp() unpins leaf pages */ split.mp = mp; split.index = index + 1; split.flag = XAD_NEW; split.off = xoff; /* split offset */ split.len = len; split.addr = xaddr; split.pxdlist = NULL; if ((rc = xtSplitUp(tid, ip, &split, &btstack))) return rc; /* get back old page */ XT_GETPAGE(ip, bn, mp, PSIZE, p, rc); if (rc) return rc; /* * if leaf root has been split, original root has been * copied to new child page, i.e., original entry now * resides on the new child page; */ if (p->header.flag & BT_INTERNAL) { ASSERT(p->header.nextindex == cpu_to_le16(XTENTRYSTART + 1)); xad = &p->xad[XTENTRYSTART]; bn = addressXAD(xad); XT_PUTPAGE(mp); /* get new child page */ XT_GETPAGE(ip, bn, mp, PSIZE, p, rc); if (rc) return rc; BT_MARK_DIRTY(mp, ip); if (!test_cflag(COMMIT_Nolink, ip)) { tlck = txLock(tid, ip, mp, tlckXTREE|tlckGROW); xtlck = (struct xtlock *) & tlck->lock; } } } /* * insert the new entry into the leaf page */ else { /* insert the new entry: mark the entry NEW */ xad = &p->xad[index + 1]; XT_PUTENTRY(xad, XAD_NEW, xoff, len, xaddr); /* advance next available entry index */ le16_add_cpu(&p->header.nextindex, 1); } /* get back old entry */ xad = &p->xad[index]; xlen = MAXXLEN; /* * extend old extent */ extendOld: XADlength(xad, xlen); if (!(xad->flag & XAD_NEW)) xad->flag |= XAD_EXTENDED; if (!test_cflag(COMMIT_Nolink, ip)) { xtlck->lwm.offset = (xtlck->lwm.offset) ? min(index, (int)xtlck->lwm.offset) : index; xtlck->lwm.length = le16_to_cpu(p->header.nextindex) - xtlck->lwm.offset; } /* unpin the leaf page */ XT_PUTPAGE(mp); return rc; } #ifdef _NOTYET /* * xtTailgate() * * function: split existing 'tail' extent * (split offset >= start offset of tail extent), and * relocate and extend the split tail half; * * note: existing extent may or may not have been committed. * caller is responsible for pager buffer cache update, and * working block allocation map update; * update pmap: free old split tail extent, alloc new extent; */ int xtTailgate(tid_t tid, /* transaction id */ struct inode *ip, s64 xoff, /* split/new extent offset */ s32 xlen, /* new extent length */ s64 xaddr, /* new extent address */ int flag) { int rc = 0; int cmp; struct metapage *mp; /* meta-page buffer */ xtpage_t *p; /* base B+-tree index page */ s64 bn; int index, nextindex, llen, rlen; struct btstack btstack; /* traverse stack */ struct xtsplit split; /* split information */ xad_t *xad; struct tlock *tlck; struct xtlock *xtlck = 0; struct tlock *mtlck; struct maplock *pxdlock; /* printf("xtTailgate: nxoff:0x%lx nxlen:0x%x nxaddr:0x%lx\n", (ulong)xoff, xlen, (ulong)xaddr); */ /* there must exist extent to be tailgated */ if ((rc = xtSearch(ip, xoff, NULL, &cmp, &btstack, XT_INSERT))) return rc; /* retrieve search result */ XT_GETSEARCH(ip, btstack.top, bn, mp, p, index); if (cmp != 0) { XT_PUTPAGE(mp); jfs_error(ip->i_sb, "xtTailgate: couldn't find extent"); return -EIO; } /* entry found must be last entry */ nextindex = le16_to_cpu(p->header.nextindex); if (index != nextindex - 1) { XT_PUTPAGE(mp); jfs_error(ip->i_sb, "xtTailgate: the entry found is not the last entry"); return -EIO; } BT_MARK_DIRTY(mp, ip); /* * acquire tlock of the leaf page containing original entry */ if (!test_cflag(COMMIT_Nolink, ip)) { tlck = txLock(tid, ip, mp, tlckXTREE | tlckGROW); xtlck = (struct xtlock *) & tlck->lock; } /* completely replace extent ? */ xad = &p->xad[index]; /* printf("xtTailgate: xoff:0x%lx xlen:0x%x xaddr:0x%lx\n", (ulong)offsetXAD(xad), lengthXAD(xad), (ulong)addressXAD(xad)); */ if ((llen = xoff - offsetXAD(xad)) == 0) goto updateOld; /* * partially replace extent: insert entry for new extent */ //insertNew: /* * if the leaf page is full, insert the new entry and * propagate up the router entry for the new page from split * * The xtSplitUp() will insert the entry and unpin the leaf page. */ if (nextindex == le16_to_cpu(p->header.maxentry)) { /* xtSpliUp() unpins leaf pages */ split.mp = mp; split.index = index + 1; split.flag = XAD_NEW; split.off = xoff; /* split offset */ split.len = xlen; split.addr = xaddr; split.pxdlist = NULL; if ((rc = xtSplitUp(tid, ip, &split, &btstack))) return rc; /* get back old page */ XT_GETPAGE(ip, bn, mp, PSIZE, p, rc); if (rc) return rc; /* * if leaf root has been split, original root has been * copied to new child page, i.e., original entry now * resides on the new child page; */ if (p->header.flag & BT_INTERNAL) { ASSERT(p->header.nextindex == cpu_to_le16(XTENTRYSTART + 1)); xad = &p->xad[XTENTRYSTART]; bn = addressXAD(xad); XT_PUTPAGE(mp); /* get new child page */ XT_GETPAGE(ip, bn, mp, PSIZE, p, rc); if (rc) return rc; BT_MARK_DIRTY(mp, ip); if (!test_cflag(COMMIT_Nolink, ip)) { tlck = txLock(tid, ip, mp, tlckXTREE|tlckGROW); xtlck = (struct xtlock *) & tlck->lock; } } } /* * insert the new entry into the leaf page */ else { /* insert the new entry: mark the entry NEW */ xad = &p->xad[index + 1]; XT_PUTENTRY(xad, XAD_NEW, xoff, xlen, xaddr); /* advance next available entry index */ le16_add_cpu(&p->header.nextindex, 1); } /* get back old XAD */ xad = &p->xad[index]; /* * truncate/relocate old extent at split offset */ updateOld: /* update dmap for old/committed/truncated extent */ rlen = lengthXAD(xad) - llen; if (!(xad->flag & XAD_NEW)) { /* free from PWMAP at commit */ if (!test_cflag(COMMIT_Nolink, ip)) { mtlck = txMaplock(tid, ip, tlckMAP); pxdlock = (struct maplock *) & mtlck->lock; pxdlock->flag = mlckFREEPXD; PXDaddress(&pxdlock->pxd, addressXAD(xad) + llen); PXDlength(&pxdlock->pxd, rlen); pxdlock->index = 1; } } else /* free from WMAP */ dbFree(ip, addressXAD(xad) + llen, (s64) rlen); if (llen) /* truncate */ XADlength(xad, llen); else /* replace */ XT_PUTENTRY(xad, XAD_NEW, xoff, xlen, xaddr); if (!test_cflag(COMMIT_Nolink, ip)) { xtlck->lwm.offset = (xtlck->lwm.offset) ? min(index, (int)xtlck->lwm.offset) : index; xtlck->lwm.length = le16_to_cpu(p->header.nextindex) - xtlck->lwm.offset; } /* unpin the leaf page */ XT_PUTPAGE(mp); return rc; } #endif /* _NOTYET */ /* * xtUpdate() * * function: update XAD; * * update extent for allocated_but_not_recorded or * compressed extent; * * parameter: * nxad - new XAD; * logical extent of the specified XAD must be completely * contained by an existing XAD; */ int xtUpdate(tid_t tid, struct inode *ip, xad_t * nxad) { /* new XAD */ int rc = 0; int cmp; struct metapage *mp; /* meta-page buffer */ xtpage_t *p; /* base B+-tree index page */ s64 bn; int index0, index, newindex, nextindex; struct btstack btstack; /* traverse stack */ struct xtsplit split; /* split information */ xad_t *xad, *lxad, *rxad; int xflag; s64 nxoff, xoff; int nxlen, xlen, lxlen, rxlen; s64 nxaddr, xaddr; struct tlock *tlck; struct xtlock *xtlck = NULL; int newpage = 0; /* there must exist extent to be tailgated */ nxoff = offsetXAD(nxad); nxlen = lengthXAD(nxad); nxaddr = addressXAD(nxad); if ((rc = xtSearch(ip, nxoff, NULL, &cmp, &btstack, XT_INSERT))) return rc; /* retrieve search result */ XT_GETSEARCH(ip, btstack.top, bn, mp, p, index0); if (cmp != 0) { XT_PUTPAGE(mp); jfs_error(ip->i_sb, "xtUpdate: Could not find extent"); return -EIO; } BT_MARK_DIRTY(mp, ip); /* * acquire tlock of the leaf page containing original entry */ if (!test_cflag(COMMIT_Nolink, ip)) { tlck = txLock(tid, ip, mp, tlckXTREE | tlckGROW); xtlck = (struct xtlock *) & tlck->lock; } xad = &p->xad[index0]; xflag = xad->flag; xoff = offsetXAD(xad); xlen = lengthXAD(xad); xaddr = addressXAD(xad); /* nXAD must be completely contained within XAD */ if ((xoff > nxoff) || (nxoff + nxlen > xoff + xlen)) { XT_PUTPAGE(mp); jfs_error(ip->i_sb, "xtUpdate: nXAD in not completely contained within XAD"); return -EIO; } index = index0; newindex = index + 1; nextindex = le16_to_cpu(p->header.nextindex); #ifdef _JFS_WIP_NOCOALESCE if (xoff < nxoff) goto updateRight; /* * replace XAD with nXAD */ replace: /* (nxoff == xoff) */ if (nxlen == xlen) { /* replace XAD with nXAD:recorded */ *xad = *nxad; xad->flag = xflag & ~XAD_NOTRECORDED; goto out; } else /* (nxlen < xlen) */ goto updateLeft; #endif /* _JFS_WIP_NOCOALESCE */ /* #ifdef _JFS_WIP_COALESCE */ if (xoff < nxoff) goto coalesceRight; /* * coalesce with left XAD */ //coalesceLeft: /* (xoff == nxoff) */ /* is XAD first entry of page ? */ if (index == XTENTRYSTART) goto replace; /* is nXAD logically and physically contiguous with lXAD ? */ lxad = &p->xad[index - 1]; lxlen = lengthXAD(lxad); if (!(lxad->flag & XAD_NOTRECORDED) && (nxoff == offsetXAD(lxad) + lxlen) && (nxaddr == addressXAD(lxad) + lxlen) && (lxlen + nxlen < MAXXLEN)) { /* extend right lXAD */ index0 = index - 1; XADlength(lxad, lxlen + nxlen); /* If we just merged two extents together, need to make sure the * right extent gets logged. If the left one is marked XAD_NEW, * then we know it will be logged. Otherwise, mark as * XAD_EXTENDED */ if (!(lxad->flag & XAD_NEW)) lxad->flag |= XAD_EXTENDED; if (xlen > nxlen) { /* truncate XAD */ XADoffset(xad, xoff + nxlen); XADlength(xad, xlen - nxlen); XADaddress(xad, xaddr + nxlen); goto out; } else { /* (xlen == nxlen) */ /* remove XAD */ if (index < nextindex - 1) memmove(&p->xad[index], &p->xad[index + 1], (nextindex - index - 1) << L2XTSLOTSIZE); p->header.nextindex = cpu_to_le16(le16_to_cpu(p->header.nextindex) - 1); index = index0; newindex = index + 1; nextindex = le16_to_cpu(p->header.nextindex); xoff = nxoff = offsetXAD(lxad); xlen = nxlen = lxlen + nxlen; xaddr = nxaddr = addressXAD(lxad); goto coalesceRight; } } /* * replace XAD with nXAD */ replace: /* (nxoff == xoff) */ if (nxlen == xlen) { /* replace XAD with nXAD:recorded */ *xad = *nxad; xad->flag = xflag & ~XAD_NOTRECORDED; goto coalesceRight; } else /* (nxlen < xlen) */ goto updateLeft; /* * coalesce with right XAD */ coalesceRight: /* (xoff <= nxoff) */ /* is XAD last entry of page ? */ if (newindex == nextindex) { if (xoff == nxoff) goto out; goto updateRight; } /* is nXAD logically and physically contiguous with rXAD ? */ rxad = &p->xad[index + 1]; rxlen = lengthXAD(rxad); if (!(rxad->flag & XAD_NOTRECORDED) && (nxoff + nxlen == offsetXAD(rxad)) && (nxaddr + nxlen == addressXAD(rxad)) && (rxlen + nxlen < MAXXLEN)) { /* extend left rXAD */ XADoffset(rxad, nxoff); XADlength(rxad, rxlen + nxlen); XADaddress(rxad, nxaddr); /* If we just merged two extents together, need to make sure * the left extent gets logged. If the right one is marked * XAD_NEW, then we know it will be logged. Otherwise, mark as * XAD_EXTENDED */ if (!(rxad->flag & XAD_NEW)) rxad->flag |= XAD_EXTENDED; if (xlen > nxlen) /* truncate XAD */ XADlength(xad, xlen - nxlen); else { /* (xlen == nxlen) */ /* remove XAD */ memmove(&p->xad[index], &p->xad[index + 1], (nextindex - index - 1) << L2XTSLOTSIZE); p->header.nextindex = cpu_to_le16(le16_to_cpu(p->header.nextindex) - 1); } goto out; } else if (xoff == nxoff) goto out; if (xoff >= nxoff) { XT_PUTPAGE(mp); jfs_error(ip->i_sb, "xtUpdate: xoff >= nxoff"); return -EIO; } /* #endif _JFS_WIP_COALESCE */ /* * split XAD into (lXAD, nXAD): * * |---nXAD---> * --|----------XAD----------|-- * |-lXAD-| */ updateRight: /* (xoff < nxoff) */ /* truncate old XAD as lXAD:not_recorded */ xad = &p->xad[index]; XADlength(xad, nxoff - xoff); /* insert nXAD:recorded */ if (nextindex == le16_to_cpu(p->header.maxentry)) { /* xtSpliUp() unpins leaf pages */ split.mp = mp; split.index = newindex; split.flag = xflag & ~XAD_NOTRECORDED; split.off = nxoff; split.len = nxlen; split.addr = nxaddr; split.pxdlist = NULL; if ((rc = xtSplitUp(tid, ip, &split, &btstack))) return rc; /* get back old page */ XT_GETPAGE(ip, bn, mp, PSIZE, p, rc); if (rc) return rc; /* * if leaf root has been split, original root has been * copied to new child page, i.e., original entry now * resides on the new child page; */ if (p->header.flag & BT_INTERNAL) { ASSERT(p->header.nextindex == cpu_to_le16(XTENTRYSTART + 1)); xad = &p->xad[XTENTRYSTART]; bn = addressXAD(xad); XT_PUTPAGE(mp); /* get new child page */ XT_GETPAGE(ip, bn, mp, PSIZE, p, rc); if (rc) return rc; BT_MARK_DIRTY(mp, ip); if (!test_cflag(COMMIT_Nolink, ip)) { tlck = txLock(tid, ip, mp, tlckXTREE|tlckGROW); xtlck = (struct xtlock *) & tlck->lock; } } else { /* is nXAD on new page ? */ if (newindex > (le16_to_cpu(p->header.maxentry) >> 1)) { newindex = newindex - le16_to_cpu(p->header.nextindex) + XTENTRYSTART; newpage = 1; } } } else { /* if insert into middle, shift right remaining entries */ if (newindex < nextindex) memmove(&p->xad[newindex + 1], &p->xad[newindex], (nextindex - newindex) << L2XTSLOTSIZE); /* insert the entry */ xad = &p->xad[newindex]; *xad = *nxad; xad->flag = xflag & ~XAD_NOTRECORDED; /* advance next available entry index. */ p->header.nextindex = cpu_to_le16(le16_to_cpu(p->header.nextindex) + 1); } /* * does nXAD force 3-way split ? * * |---nXAD--->| * --|----------XAD-------------|-- * |-lXAD-| |-rXAD -| */ if (nxoff + nxlen == xoff + xlen) goto out; /* reorient nXAD as XAD for further split XAD into (nXAD, rXAD) */ if (newpage) { /* close out old page */ if (!test_cflag(COMMIT_Nolink, ip)) { xtlck->lwm.offset = (xtlck->lwm.offset) ? min(index0, (int)xtlck->lwm.offset) : index0; xtlck->lwm.length = le16_to_cpu(p->header.nextindex) - xtlck->lwm.offset; } bn = le64_to_cpu(p->header.next); XT_PUTPAGE(mp); /* get new right page */ XT_GETPAGE(ip, bn, mp, PSIZE, p, rc); if (rc) return rc; BT_MARK_DIRTY(mp, ip); if (!test_cflag(COMMIT_Nolink, ip)) { tlck = txLock(tid, ip, mp, tlckXTREE | tlckGROW); xtlck = (struct xtlock *) & tlck->lock; } index0 = index = newindex; } else index++; newindex = index + 1; nextindex = le16_to_cpu(p->header.nextindex); xlen = xlen - (nxoff - xoff); xoff = nxoff; xaddr = nxaddr; /* recompute split pages */ if (nextindex == le16_to_cpu(p->header.maxentry)) { XT_PUTPAGE(mp); if ((rc = xtSearch(ip, nxoff, NULL, &cmp, &btstack, XT_INSERT))) return rc; /* retrieve search result */ XT_GETSEARCH(ip, btstack.top, bn, mp, p, index0); if (cmp != 0) { XT_PUTPAGE(mp); jfs_error(ip->i_sb, "xtUpdate: xtSearch failed"); return -EIO; } if (index0 != index) { XT_PUTPAGE(mp); jfs_error(ip->i_sb, "xtUpdate: unexpected value of index"); return -EIO; } } /* * split XAD into (nXAD, rXAD) * * ---nXAD---| * --|----------XAD----------|-- * |-rXAD-| */ updateLeft: /* (nxoff == xoff) && (nxlen < xlen) */ /* update old XAD with nXAD:recorded */ xad = &p->xad[index]; *xad = *nxad; xad->flag = xflag & ~XAD_NOTRECORDED; /* insert rXAD:not_recorded */ xoff = xoff + nxlen; xlen = xlen - nxlen; xaddr = xaddr + nxlen; if (nextindex == le16_to_cpu(p->header.maxentry)) { /* printf("xtUpdate.updateLeft.split p:0x%p\n", p); */ /* xtSpliUp() unpins leaf pages */ split.mp = mp; split.index = newindex; split.flag = xflag; split.off = xoff; split.len = xlen; split.addr = xaddr; split.pxdlist = NULL; if ((rc = xtSplitUp(tid, ip, &split, &btstack))) return rc; /* get back old page */ XT_GETPAGE(ip, bn, mp, PSIZE, p, rc); if (rc) return rc; /* * if leaf root has been split, original root has been * copied to new child page, i.e., original entry now * resides on the new child page; */ if (p->header.flag & BT_INTERNAL) { ASSERT(p->header.nextindex == cpu_to_le16(XTENTRYSTART + 1)); xad = &p->xad[XTENTRYSTART]; bn = addressXAD(xad); XT_PUTPAGE(mp); /* get new child page */ XT_GETPAGE(ip, bn, mp, PSIZE, p, rc); if (rc) return rc; BT_MARK_DIRTY(mp, ip); if (!test_cflag(COMMIT_Nolink, ip)) { tlck = txLock(tid, ip, mp, tlckXTREE|tlckGROW); xtlck = (struct xtlock *) & tlck->lock; } } } else { /* if insert into middle, shift right remaining entries */ if (newindex < nextindex) memmove(&p->xad[newindex + 1], &p->xad[newindex], (nextindex - newindex) << L2XTSLOTSIZE); /* insert the entry */ xad = &p->xad[newindex]; XT_PUTENTRY(xad, xflag, xoff, xlen, xaddr); /* advance next available entry index. */ p->header.nextindex = cpu_to_le16(le16_to_cpu(p->header.nextindex) + 1); } out: if (!test_cflag(COMMIT_Nolink, ip)) { xtlck->lwm.offset = (xtlck->lwm.offset) ? min(index0, (int)xtlck->lwm.offset) : index0; xtlck->lwm.length = le16_to_cpu(p->header.nextindex) - xtlck->lwm.offset; } /* unpin the leaf page */ XT_PUTPAGE(mp); return rc; } /* * xtAppend() * * function: grow in append mode from contiguous region specified ; * * parameter: * tid - transaction id; * ip - file object; * xflag - extent flag: * xoff - extent offset; * maxblocks - max extent length; * xlen - extent length (in/out); * xaddrp - extent address pointer (in/out): * flag - * * return: */ int xtAppend(tid_t tid, /* transaction id */ struct inode *ip, int xflag, s64 xoff, s32 maxblocks, s32 * xlenp, /* (in/out) */ s64 * xaddrp, /* (in/out) */ int flag) { int rc = 0; struct metapage *mp; /* meta-page buffer */ xtpage_t *p; /* base B+-tree index page */ s64 bn, xaddr; int index, nextindex; struct btstack btstack; /* traverse stack */ struct xtsplit split; /* split information */ xad_t *xad; int cmp; struct tlock *tlck; struct xtlock *xtlck; int nsplit, nblocks, xlen; struct pxdlist pxdlist; pxd_t *pxd; s64 next; xaddr = *xaddrp; xlen = *xlenp; jfs_info("xtAppend: xoff:0x%lx maxblocks:%d xlen:%d xaddr:0x%lx", (ulong) xoff, maxblocks, xlen, (ulong) xaddr); /* * search for the entry location at which to insert: * * xtFastSearch() and xtSearch() both returns (leaf page * pinned, index at which to insert). * n.b. xtSearch() may return index of maxentry of * the full page. */ if ((rc = xtSearch(ip, xoff, &next, &cmp, &btstack, XT_INSERT))) return rc; /* retrieve search result */ XT_GETSEARCH(ip, btstack.top, bn, mp, p, index); if (cmp == 0) { rc = -EEXIST; goto out; } if (next) xlen = min(xlen, (int)(next - xoff)); //insert: /* * insert entry for new extent */ xflag |= XAD_NEW; /* * if the leaf page is full, split the page and * propagate up the router entry for the new page from split * * The xtSplitUp() will insert the entry and unpin the leaf page. */ nextindex = le16_to_cpu(p->header.nextindex); if (nextindex < le16_to_cpu(p->header.maxentry)) goto insertLeaf; /* * allocate new index blocks to cover index page split(s) */ nsplit = btstack.nsplit; split.pxdlist = &pxdlist; pxdlist.maxnpxd = pxdlist.npxd = 0; pxd = &pxdlist.pxd[0]; nblocks = JFS_SBI(ip->i_sb)->nbperpage; for (; nsplit > 0; nsplit--, pxd++, xaddr += nblocks, maxblocks -= nblocks) { if ((rc = dbAllocBottomUp(ip, xaddr, (s64) nblocks)) == 0) { PXDaddress(pxd, xaddr); PXDlength(pxd, nblocks); pxdlist.maxnpxd++; continue; } /* undo allocation */ goto out; } xlen = min(xlen, maxblocks); /* * allocate data extent requested */ if ((rc = dbAllocBottomUp(ip, xaddr, (s64) xlen))) goto out; split.mp = mp; split.index = index; split.flag = xflag; split.off = xoff; split.len = xlen; split.addr = xaddr; if ((rc = xtSplitUp(tid, ip, &split, &btstack))) { /* undo data extent allocation */ dbFree(ip, *xaddrp, (s64) * xlenp); return rc; } *xaddrp = xaddr; *xlenp = xlen; return 0; /* * insert the new entry into the leaf page */ insertLeaf: /* * allocate data extent requested */ if ((rc = dbAllocBottomUp(ip, xaddr, (s64) xlen))) goto out; BT_MARK_DIRTY(mp, ip); /* * acquire a transaction lock on the leaf page; * * action: xad insertion/extension; */ tlck = txLock(tid, ip, mp, tlckXTREE | tlckGROW); xtlck = (struct xtlock *) & tlck->lock; /* insert the new entry: mark the entry NEW */ xad = &p->xad[index]; XT_PUTENTRY(xad, xflag, xoff, xlen, xaddr); /* advance next available entry index */ le16_add_cpu(&p->header.nextindex, 1); xtlck->lwm.offset = (xtlck->lwm.offset) ? min(index,(int) xtlck->lwm.offset) : index; xtlck->lwm.length = le16_to_cpu(p->header.nextindex) - xtlck->lwm.offset; *xaddrp = xaddr; *xlenp = xlen; out: /* unpin the leaf page */ XT_PUTPAGE(mp); return rc; } #ifdef _STILL_TO_PORT /* - TBD for defragmentaion/reorganization - * * xtDelete() * * function: * delete the entry with the specified key. * * N.B.: whole extent of the entry is assumed to be deleted. * * parameter: * * return: * ENOENT: if the entry is not found. * * exception: */ int xtDelete(tid_t tid, struct inode *ip, s64 xoff, s32 xlen, int flag) { int rc = 0; struct btstack btstack; int cmp; s64 bn; struct metapage *mp; xtpage_t *p; int index, nextindex; struct tlock *tlck; struct xtlock *xtlck; /* * find the matching entry; xtSearch() pins the page */ if ((rc = xtSearch(ip, xoff, NULL, &cmp, &btstack, 0))) return rc; XT_GETSEARCH(ip, btstack.top, bn, mp, p, index); if (cmp) { /* unpin the leaf page */ XT_PUTPAGE(mp); return -ENOENT; } /* * delete the entry from the leaf page */ nextindex = le16_to_cpu(p->header.nextindex); le16_add_cpu(&p->header.nextindex, -1); /* * if the leaf page bocome empty, free the page */ if (p->header.nextindex == cpu_to_le16(XTENTRYSTART)) return (xtDeleteUp(tid, ip, mp, p, &btstack)); BT_MARK_DIRTY(mp, ip); /* * acquire a transaction lock on the leaf page; * * action:xad deletion; */ tlck = txLock(tid, ip, mp, tlckXTREE); xtlck = (struct xtlock *) & tlck->lock; xtlck->lwm.offset = (xtlck->lwm.offset) ? min(index, xtlck->lwm.offset) : index; /* if delete from middle, shift left/compact the remaining entries */ if (index < nextindex - 1) memmove(&p->xad[index], &p->xad[index + 1], (nextindex - index - 1) * sizeof(xad_t)); XT_PUTPAGE(mp); return 0; } /* - TBD for defragmentaion/reorganization - * * xtDeleteUp() * * function: * free empty pages as propagating deletion up the tree * * parameter: * * return: */ static int xtDeleteUp(tid_t tid, struct inode *ip, struct metapage * fmp, xtpage_t * fp, struct btstack * btstack) { int rc = 0; struct metapage *mp; xtpage_t *p; int index, nextindex; s64 xaddr; int xlen; struct btframe *parent; struct tlock *tlck; struct xtlock *xtlck; /* * keep root leaf page which has become empty */ if (fp->header.flag & BT_ROOT) { /* keep the root page */ fp->header.flag &= ~BT_INTERNAL; fp->header.flag |= BT_LEAF; fp->header.nextindex = cpu_to_le16(XTENTRYSTART); /* XT_PUTPAGE(fmp); */ return 0; } /* * free non-root leaf page */ if ((rc = xtRelink(tid, ip, fp))) { XT_PUTPAGE(fmp); return rc; } xaddr = addressPXD(&fp->header.self); xlen = lengthPXD(&fp->header.self); /* free the page extent */ dbFree(ip, xaddr, (s64) xlen); /* free the buffer page */ discard_metapage(fmp); /* * propagate page deletion up the index 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) { /* get/pin the parent page <sp> */ XT_GETPAGE(ip, parent->bn, mp, PSIZE, p, rc); if (rc) return rc; index = parent->index; /* delete the entry for the freed child page from parent. */ nextindex = le16_to_cpu(p->header.nextindex); /* * the parent has the single entry being deleted: * free the parent page which has become empty. */ if (nextindex == 1) { if (p->header.flag & BT_ROOT) { /* keep the root page */ p->header.flag &= ~BT_INTERNAL; p->header.flag |= BT_LEAF; p->header.nextindex = cpu_to_le16(XTENTRYSTART); /* XT_PUTPAGE(mp); */ break; } else { /* free the parent page */ if ((rc = xtRelink(tid, ip, p))) return rc; xaddr = addressPXD(&p->header.self); /* free the page extent */ dbFree(ip, xaddr, (s64) JFS_SBI(ip->i_sb)->nbperpage); /* unpin/free the buffer page */ discard_metapage(mp); /* propagate up */ continue; } } /* * the parent has other entries remaining: * delete the router entry from the parent page. */ else { BT_MARK_DIRTY(mp, ip); /* * acquire a transaction lock on the leaf page; * * action:xad deletion; */ tlck = txLock(tid, ip, mp, tlckXTREE); xtlck = (struct xtlock *) & tlck->lock; xtlck->lwm.offset = (xtlck->lwm.offset) ? min(index, xtlck->lwm. offset) : index; /* if delete from middle, * shift left/compact the remaining entries in the page */ if (index < nextindex - 1) memmove(&p->xad[index], &p->xad[index + 1], (nextindex - index - 1) << L2XTSLOTSIZE); le16_add_cpu(&p->header.nextindex, -1); jfs_info("xtDeleteUp(entry): 0x%lx[%d]", (ulong) parent->bn, index); } /* unpin the parent page */ XT_PUTPAGE(mp); /* exit propagation up */ break; } return 0; } /* * NAME: xtRelocate() * * FUNCTION: relocate xtpage or data extent of regular file; * This function is mainly used by defragfs utility. * * NOTE: This routine does not have the logic to handle * uncommitted allocated extent. The caller should call * txCommit() to commit all the allocation before call * this routine. */ int xtRelocate(tid_t tid, struct inode * ip, xad_t * oxad, /* old XAD */ s64 nxaddr, /* new xaddr */ int xtype) { /* extent type: XTPAGE or DATAEXT */ int rc = 0; struct tblock *tblk; struct tlock *tlck; struct xtlock *xtlck; struct metapage *mp, *pmp, *lmp, *rmp; /* meta-page buffer */ xtpage_t *p, *pp, *rp, *lp; /* base B+-tree index page */ xad_t *xad; pxd_t *pxd; s64 xoff, xsize; int xlen; s64 oxaddr, sxaddr, dxaddr, nextbn, prevbn; cbuf_t *cp; s64 offset, nbytes, nbrd, pno; int nb, npages, nblks; s64 bn; int cmp; int index; struct pxd_lock *pxdlock; struct btstack btstack; /* traverse stack */ xtype = xtype & EXTENT_TYPE; xoff = offsetXAD(oxad); oxaddr = addressXAD(oxad); xlen = lengthXAD(oxad); /* validate extent offset */ offset = xoff << JFS_SBI(ip->i_sb)->l2bsize; if (offset >= ip->i_size) return -ESTALE; /* stale extent */ jfs_info("xtRelocate: xtype:%d xoff:0x%lx xlen:0x%x xaddr:0x%lx:0x%lx", xtype, (ulong) xoff, xlen, (ulong) oxaddr, (ulong) nxaddr); /* * 1. get and validate the parent xtpage/xad entry * covering the source extent to be relocated; */ if (xtype == DATAEXT) { /* search in leaf entry */ rc = xtSearch(ip, xoff, NULL, &cmp, &btstack, 0); if (rc) return rc; /* retrieve search result */ XT_GETSEARCH(ip, btstack.top, bn, pmp, pp, index); if (cmp) { XT_PUTPAGE(pmp); return -ESTALE; } /* validate for exact match with a single entry */ xad = &pp->xad[index]; if (addressXAD(xad) != oxaddr || lengthXAD(xad) != xlen) { XT_PUTPAGE(pmp); return -ESTALE; } } else { /* (xtype == XTPAGE) */ /* search in internal entry */ rc = xtSearchNode(ip, oxad, &cmp, &btstack, 0); if (rc) return rc; /* retrieve search result */ XT_GETSEARCH(ip, btstack.top, bn, pmp, pp, index); if (cmp) { XT_PUTPAGE(pmp); return -ESTALE; } /* xtSearchNode() validated for exact match with a single entry */ xad = &pp->xad[index]; } jfs_info("xtRelocate: parent xad entry validated."); /* * 2. relocate the extent */ if (xtype == DATAEXT) { /* if the extent is allocated-but-not-recorded * there is no real data to be moved in this extent, */ if (xad->flag & XAD_NOTRECORDED) goto out; else /* release xtpage for cmRead()/xtLookup() */ XT_PUTPAGE(pmp); /* * cmRelocate() * * copy target data pages to be relocated; * * data extent must start at page boundary and * multiple of page size (except the last data extent); * read in each page of the source data extent into cbuf, * update the cbuf extent descriptor of the page to be * homeward bound to new dst data extent * copy the data from the old extent to new extent. * copy is essential for compressed files to avoid problems * that can arise if there was a change in compression * algorithms. * it is a good strategy because it may disrupt cache * policy to keep the pages in memory afterwards. */ offset = xoff << JFS_SBI(ip->i_sb)->l2bsize; assert((offset & CM_OFFSET) == 0); nbytes = xlen << JFS_SBI(ip->i_sb)->l2bsize; pno = offset >> CM_L2BSIZE; npages = (nbytes + (CM_BSIZE - 1)) >> CM_L2BSIZE; /* npages = ((offset + nbytes - 1) >> CM_L2BSIZE) - (offset >> CM_L2BSIZE) + 1; */ sxaddr = oxaddr; dxaddr = nxaddr; /* process the request one cache buffer at a time */ for (nbrd = 0; nbrd < nbytes; nbrd += nb, offset += nb, pno++, npages--) { /* compute page size */ nb = min(nbytes - nbrd, CM_BSIZE); /* get the cache buffer of the page */ if (rc = cmRead(ip, offset, npages, &cp)) break; assert(addressPXD(&cp->cm_pxd) == sxaddr); assert(!cp->cm_modified); /* bind buffer with the new extent address */ nblks = nb >> JFS_IP(ip->i_sb)->l2bsize; cmSetXD(ip, cp, pno, dxaddr, nblks); /* release the cbuf, mark it as modified */ cmPut(cp, true); dxaddr += nblks; sxaddr += nblks; } /* get back parent page */ if ((rc = xtSearch(ip, xoff, NULL, &cmp, &btstack, 0))) return rc; XT_GETSEARCH(ip, btstack.top, bn, pmp, pp, index); jfs_info("xtRelocate: target data extent relocated."); } else { /* (xtype == XTPAGE) */ /* * read in the target xtpage from the source extent; */ XT_GETPAGE(ip, oxaddr, mp, PSIZE, p, rc); if (rc) { XT_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); XT_GETPAGE(ip, nextbn, rmp, PSIZE, rp, rc); if (rc) { XT_PUTPAGE(pmp); XT_PUTPAGE(mp); return (rc); } } lmp = NULL; if (p->header.prev) { prevbn = le64_to_cpu(p->header.prev); XT_GETPAGE(ip, prevbn, lmp, PSIZE, lp, rc); if (rc) { XT_PUTPAGE(pmp); XT_PUTPAGE(mp); if (rmp) XT_PUTPAGE(rmp); return (rc); } } /* at this point, all xtpages to be updated are in memory */ /* * update sibling pointers of sibling xtpages if any; */ if (lmp) { BT_MARK_DIRTY(lmp, ip); tlck = txLock(tid, ip, lmp, tlckXTREE | tlckRELINK); lp->header.next = cpu_to_le64(nxaddr); XT_PUTPAGE(lmp); } if (rmp) { BT_MARK_DIRTY(rmp, ip); tlck = txLock(tid, ip, rmp, tlckXTREE | tlckRELINK); rp->header.prev = cpu_to_le64(nxaddr); XT_PUTPAGE(rmp); } /* * update the target xtpage to be relocated * * update the self address of the target page * and write to destination extent; * redo image covers the whole xtpage since it is new page * to the destination extent; * update of bmap for the free of source extent * of the target xtpage itself: * update of bmap for the allocation of destination extent * of the target xtpage itself: * update of bmap for the extents covered by xad entries in * the target xtpage is not necessary since they are not * updated; * if not committed before this relocation, * target page may contain XAD_NEW entries which must * be scanned for bmap update (logredo() always * scan xtpage REDOPAGE image for bmap update); * if committed before this relocation (tlckRELOCATE), * scan may be skipped by commit() and logredo(); */ BT_MARK_DIRTY(mp, ip); /* tlckNEW init xtlck->lwm.offset = XTENTRYSTART; */ tlck = txLock(tid, ip, mp, tlckXTREE | tlckNEW); xtlck = (struct xtlock *) & tlck->lock; /* update the self address in the xtpage header */ pxd = &p->header.self; PXDaddress(pxd, nxaddr); /* linelock for the after image of the whole page */ xtlck->lwm.length = le16_to_cpu(p->header.nextindex) - xtlck->lwm.offset; /* update the buffer extent descriptor of target xtpage */ xsize = xlen << JFS_SBI(ip->i_sb)->l2bsize; bmSetXD(mp, nxaddr, xsize); /* unpin the target page to new homeward bound */ XT_PUTPAGE(mp); jfs_info("xtRelocate: target xtpage relocated."); } /* * 3. acquire maplock for the source extent to be freed; * * acquire a maplock saving the src relocated extent address; * to free of the extent at commit time; */ out: /* if DATAEXT relocation, write a LOG_UPDATEMAP record for * free PXD of the source data extent (logredo() will update * bmap for free of source data extent), and update bmap for * free of the source data extent; */ if (xtype == DATAEXT) tlck = txMaplock(tid, ip, tlckMAP); /* if XTPAGE relocation, write a LOG_NOREDOPAGE record * for the source xtpage (logredo() will init NoRedoPage * filter and will also update bmap for free of the source * xtpage), and update bmap for free of the source xtpage; * N.B. We use tlckMAP instead of tlkcXTREE because there * is no buffer associated with this lock since the buffer * has been redirected to the target location. */ else /* (xtype == XTPAGE) */ tlck = txMaplock(tid, ip, tlckMAP | tlckRELOCATE); pxdlock = (struct pxd_lock *) & tlck->lock; pxdlock->flag = mlckFREEPXD; PXDaddress(&pxdlock->pxd, oxaddr); PXDlength(&pxdlock->pxd, xlen); pxdlock->index = 1; /* * 4. update the parent xad entry for relocation; * * acquire tlck for the parent entry with XAD_NEW as entry * update which will write LOG_REDOPAGE and update bmap for * allocation of XAD_NEW destination extent; */ jfs_info("xtRelocate: update parent xad entry."); BT_MARK_DIRTY(pmp, ip); tlck = txLock(tid, ip, pmp, tlckXTREE | tlckGROW); xtlck = (struct xtlock *) & tlck->lock; /* update the XAD with the new destination extent; */ xad = &pp->xad[index]; xad->flag |= XAD_NEW; XADaddress(xad, nxaddr); xtlck->lwm.offset = min(index, xtlck->lwm.offset); xtlck->lwm.length = le16_to_cpu(pp->header.nextindex) - xtlck->lwm.offset; /* unpin the parent xtpage */ XT_PUTPAGE(pmp); return rc; } /* * xtSearchNode() * * function: search for the internal xad entry covering specified extent. * This function is mainly used by defragfs utility. * * parameters: * ip - file object; * xad - extent to find; * cmpp - comparison result: * btstack - traverse stack; * flag - search process flag; * * returns: * btstack contains (bn, index) of search path traversed to the entry. * *cmpp is set to result of comparison with the entry returned. * the page containing the entry is pinned at exit. */ static int xtSearchNode(struct inode *ip, xad_t * xad, /* required XAD entry */ int *cmpp, struct btstack * btstack, int flag) { int rc = 0; s64 xoff, xaddr; int xlen; int cmp = 1; /* init for empty page */ s64 bn; /* block number */ struct metapage *mp; /* meta-page buffer */ xtpage_t *p; /* page */ int base, index, lim; struct btframe *btsp; s64 t64; BT_CLR(btstack); xoff = offsetXAD(xad); xlen = lengthXAD(xad); xaddr = addressXAD(xad); /* * 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 */ XT_GETPAGE(ip, bn, mp, PSIZE, p, rc); if (rc) return rc; if (p->header.flag & BT_LEAF) { XT_PUTPAGE(mp); return -ESTALE; } lim = le16_to_cpu(p->header.nextindex) - XTENTRYSTART; /* * binary search with search key K on the current page */ for (base = XTENTRYSTART; lim; lim >>= 1) { index = base + (lim >> 1); XT_CMP(cmp, xoff, &p->xad[index], t64); if (cmp == 0) { /* * search hit * * verify for exact match; */ if (xaddr == addressXAD(&p->xad[index]) && xoff == offsetXAD(&p->xad[index])) { *cmpp = cmp; /* save search result */ btsp = btstack->top; btsp->bn = bn; btsp->index = index; btsp->mp = mp; return 0; } /* descend/search its child page */ goto next; } if (cmp > 0) { base = index + 1; --lim; } } /* * search miss - non-leaf page: * * base is the smallest index with key (Kj) greater than * search key (K) and may be zero or maxentry index. * 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 */ next: /* get the child page block number */ bn = addressXAD(&p->xad[index]); /* unpin the parent page */ XT_PUTPAGE(mp); } } /* * xtRelink() * * function: * link around a freed page. * * Parameter: * int tid, * struct inode *ip, * xtpage_t *p) * * returns: */ static int xtRelink(tid_t tid, struct inode *ip, xtpage_t * p) { int rc = 0; struct metapage *mp; s64 nextbn, prevbn; struct tlock *tlck; nextbn = le64_to_cpu(p->header.next); prevbn = le64_to_cpu(p->header.prev); /* update prev pointer of the next page */ if (nextbn != 0) { XT_GETPAGE(ip, nextbn, mp, PSIZE, p, rc); if (rc) return rc; /* * acquire a transaction lock on the page; * * action: update prev pointer; */ BT_MARK_DIRTY(mp, ip); tlck = txLock(tid, ip, mp, tlckXTREE | tlckRELINK); /* the page may already have been tlock'd */ p->header.prev = cpu_to_le64(prevbn); XT_PUTPAGE(mp); } /* update next pointer of the previous page */ if (prevbn != 0) { XT_GETPAGE(ip, prevbn, mp, PSIZE, p, rc); if (rc) return rc; /* * acquire a transaction lock on the page; * * action: update next pointer; */ BT_MARK_DIRTY(mp, ip); tlck = txLock(tid, ip, mp, tlckXTREE | tlckRELINK); /* the page may already have been tlock'd */ p->header.next = le64_to_cpu(nextbn); XT_PUTPAGE(mp); } return 0; } #endif /* _STILL_TO_PORT */ /* * xtInitRoot() * * initialize file root (inline in inode) */ void xtInitRoot(tid_t tid, struct inode *ip) { xtpage_t *p; /* * acquire a transaction lock on the root * * action: */ txLock(tid, ip, (struct metapage *) &JFS_IP(ip)->bxflag, tlckXTREE | tlckNEW); p = &JFS_IP(ip)->i_xtroot; p->header.flag = DXD_INDEX | BT_ROOT | BT_LEAF; p->header.nextindex = cpu_to_le16(XTENTRYSTART); if (S_ISDIR(ip->i_mode)) p->header.maxentry = cpu_to_le16(XTROOTINITSLOT_DIR); else { p->header.maxentry = cpu_to_le16(XTROOTINITSLOT); ip->i_size = 0; } return; } /* * We can run into a deadlock truncating a file with a large number of * xtree pages (large fragmented file). A robust fix would entail a * reservation system where we would reserve a number of metadata pages * and tlocks which we would be guaranteed without a deadlock. Without * this, a partial fix is to limit number of metadata pages we will lock * in a single transaction. Currently we will truncate the file so that * no more than 50 leaf pages will be locked. The caller of xtTruncate * will be responsible for ensuring that the current transaction gets * committed, and that subsequent transactions are created to truncate * the file further if needed. */ #define MAX_TRUNCATE_LEAVES 50 /* * xtTruncate() * * function: * traverse for truncation logging backward bottom up; * terminate at the last extent entry at the current subtree * root page covering new down size. * truncation may occur within the last extent entry. * * parameter: * int tid, * struct inode *ip, * s64 newsize, * int type) {PWMAP, PMAP, WMAP; DELETE, TRUNCATE} * * return: * * note: * PWMAP: * 1. truncate (non-COMMIT_NOLINK file) * by jfs_truncate() or jfs_open(O_TRUNC): * xtree is updated; * 2. truncate index table of directory when last entry removed * map update via tlock at commit time; * PMAP: * Call xtTruncate_pmap instead * WMAP: * 1. remove (free zero link count) on last reference release * (pmap has been freed at commit zero link count); * 2. truncate (COMMIT_NOLINK file, i.e., tmp file): * xtree is updated; * map update directly at truncation time; * * if (DELETE) * no LOG_NOREDOPAGE is required (NOREDOFILE is sufficient); * else if (TRUNCATE) * must write LOG_NOREDOPAGE for deleted index page; * * pages may already have been tlocked by anonymous transactions * during file growth (i.e., write) before truncation; * * except last truncated entry, deleted entries remains as is * in the page (nextindex is updated) for other use * (e.g., log/update allocation map): this avoid copying the page * info but delay free of pages; * */ s64 xtTruncate(tid_t tid, struct inode *ip, s64 newsize, int flag) { int rc = 0; s64 teof; struct metapage *mp; xtpage_t *p; s64 bn; int index, nextindex; xad_t *xad; s64 xoff, xaddr; int xlen, len, freexlen; struct btstack btstack; struct btframe *parent; struct tblock *tblk = NULL; struct tlock *tlck = NULL; struct xtlock *xtlck = NULL; struct xdlistlock xadlock; /* maplock for COMMIT_WMAP */ struct pxd_lock *pxdlock; /* maplock for COMMIT_WMAP */ s64 nfreed; int freed, log; int locked_leaves = 0; /* save object truncation type */ if (tid) { tblk = tid_to_tblock(tid); tblk->xflag |= flag; } nfreed = 0; flag &= COMMIT_MAP; assert(flag != COMMIT_PMAP); if (flag == COMMIT_PWMAP) log = 1; else { log = 0; xadlock.flag = mlckFREEXADLIST; xadlock.index = 1; } /* * if the newsize is not an integral number of pages, * the file between newsize and next page boundary will * be cleared. * if truncating into a file hole, it will cause * a full block to be allocated for the logical block. */ /* * release page blocks of truncated region <teof, eof> * * free the data blocks from the leaf index blocks. * delete the parent index entries corresponding to * the freed child data/index blocks. * free the index blocks themselves which aren't needed * in new sized file. * * index blocks are updated only if the blocks are to be * retained in the new sized file. * if type is PMAP, the data and index pages are NOT * freed, and the data and index blocks are NOT freed * from working map. * (this will allow continued access of data/index of * temporary file (zerolink count file truncated to zero-length)). */ teof = (newsize + (JFS_SBI(ip->i_sb)->bsize - 1)) >> JFS_SBI(ip->i_sb)->l2bsize; /* clear stack */ BT_CLR(&btstack); /* * start with root * * root resides in the inode */ bn = 0; /* * first access of each page: */ getPage: XT_GETPAGE(ip, bn, mp, PSIZE, p, rc); if (rc) return rc; /* process entries backward from last index */ index = le16_to_cpu(p->header.nextindex) - 1; /* Since this is the rightmost page at this level, and we may have * already freed a page that was formerly to the right, let's make * sure that the next pointer is zero. */ if (p->header.next) { if (log) /* * Make sure this change to the header is logged. * If we really truncate this leaf, the flag * will be changed to tlckTRUNCATE */ tlck = txLock(tid, ip, mp, tlckXTREE|tlckGROW); BT_MARK_DIRTY(mp, ip); p->header.next = 0; } if (p->header.flag & BT_INTERNAL) goto getChild; /* * leaf page */ freed = 0; /* does region covered by leaf page precede Teof ? */ xad = &p->xad[index]; xoff = offsetXAD(xad); xlen = lengthXAD(xad); if (teof >= xoff + xlen) { XT_PUTPAGE(mp); goto getParent; } /* (re)acquire tlock of the leaf page */ if (log) { if (++locked_leaves > MAX_TRUNCATE_LEAVES) { /* * We need to limit the size of the transaction * to avoid exhausting pagecache & tlocks */ XT_PUTPAGE(mp); newsize = (xoff + xlen) << JFS_SBI(ip->i_sb)->l2bsize; goto getParent; } tlck = txLock(tid, ip, mp, tlckXTREE); tlck->type = tlckXTREE | tlckTRUNCATE; xtlck = (struct xtlock *) & tlck->lock; xtlck->hwm.offset = le16_to_cpu(p->header.nextindex) - 1; } BT_MARK_DIRTY(mp, ip); /* * scan backward leaf page entries */ for (; index >= XTENTRYSTART; index--) { xad = &p->xad[index]; xoff = offsetXAD(xad); xlen = lengthXAD(xad); xaddr = addressXAD(xad); /* * The "data" for a directory is indexed by the block * device's address space. This metadata must be invalidated * here */ if (S_ISDIR(ip->i_mode) && (teof == 0)) invalidate_xad_metapages(ip, *xad); /* * entry beyond eof: continue scan of current page * xad * ---|---=======-------> * eof */ if (teof < xoff) { nfreed += xlen; continue; } /* * (xoff <= teof): last entry to be deleted from page; * If other entries remain in page: keep and update the page. */ /* * eof == entry_start: delete the entry * xad * -------|=======-------> * eof * */ if (teof == xoff) { nfreed += xlen; if (index == XTENTRYSTART) break; nextindex = index; } /* * eof within the entry: truncate the entry. * xad * -------===|===-------> * eof */ else if (teof < xoff + xlen) { /* update truncated entry */ len = teof - xoff; freexlen = xlen - len; XADlength(xad, len); /* save pxd of truncated extent in tlck */ xaddr += len; if (log) { /* COMMIT_PWMAP */ xtlck->lwm.offset = (xtlck->lwm.offset) ? min(index, (int)xtlck->lwm.offset) : index; xtlck->lwm.length = index + 1 - xtlck->lwm.offset; xtlck->twm.offset = index; pxdlock = (struct pxd_lock *) & xtlck->pxdlock; pxdlock->flag = mlckFREEPXD; PXDaddress(&pxdlock->pxd, xaddr); PXDlength(&pxdlock->pxd, freexlen); } /* free truncated extent */ else { /* COMMIT_WMAP */ pxdlock = (struct pxd_lock *) & xadlock; pxdlock->flag = mlckFREEPXD; PXDaddress(&pxdlock->pxd, xaddr); PXDlength(&pxdlock->pxd, freexlen); txFreeMap(ip, pxdlock, NULL, COMMIT_WMAP); /* reset map lock */ xadlock.flag = mlckFREEXADLIST; } /* current entry is new last entry; */ nextindex = index + 1; nfreed += freexlen; } /* * eof beyond the entry: * xad * -------=======---|---> * eof */ else { /* (xoff + xlen < teof) */ nextindex = index + 1; } if (nextindex < le16_to_cpu(p->header.nextindex)) { if (!log) { /* COMMIT_WAMP */ xadlock.xdlist = &p->xad[nextindex]; xadlock.count = le16_to_cpu(p->header.nextindex) - nextindex; txFreeMap(ip, (struct maplock *) & xadlock, NULL, COMMIT_WMAP); } p->header.nextindex = cpu_to_le16(nextindex); } XT_PUTPAGE(mp); /* assert(freed == 0); */ goto getParent; } /* end scan of leaf page entries */ freed = 1; /* * leaf page become empty: free the page if type != PMAP */ if (log) { /* COMMIT_PWMAP */ /* txCommit() with tlckFREE: * free data extents covered by leaf [XTENTRYSTART:hwm); * invalidate leaf if COMMIT_PWMAP; * if (TRUNCATE), will write LOG_NOREDOPAGE; */ tlck->type = tlckXTREE | tlckFREE; } else { /* COMMIT_WAMP */ /* free data extents covered by leaf */ xadlock.xdlist = &p->xad[XTENTRYSTART]; xadlock.count = le16_to_cpu(p->header.nextindex) - XTENTRYSTART; txFreeMap(ip, (struct maplock *) & xadlock, NULL, COMMIT_WMAP); } if (p->header.flag & BT_ROOT) { p->header.flag &= ~BT_INTERNAL; p->header.flag |= BT_LEAF; p->header.nextindex = cpu_to_le16(XTENTRYSTART); XT_PUTPAGE(mp); /* debug */ goto out; } else { if (log) { /* COMMIT_PWMAP */ /* page will be invalidated at tx completion */ XT_PUTPAGE(mp); } else { /* COMMIT_WMAP */ if (mp->lid) lid_to_tlock(mp->lid)->flag |= tlckFREELOCK; /* invalidate empty leaf page */ discard_metapage(mp); } } /* * the leaf page become empty: delete the parent entry * for the leaf page if the parent page is to be kept * in the new sized file. */ /* * go back up to the parent page */ getParent: /* pop/restore parent entry for the current child page */ if ((parent = BT_POP(&btstack)) == NULL) /* current page must have been root */ goto out; /* get back the parent page */ bn = parent->bn; XT_GETPAGE(ip, bn, mp, PSIZE, p, rc); if (rc) return rc; index = parent->index; /* * child page was not empty: */ if (freed == 0) { /* has any entry deleted from parent ? */ if (index < le16_to_cpu(p->header.nextindex) - 1) { /* (re)acquire tlock on the parent page */ if (log) { /* COMMIT_PWMAP */ /* txCommit() with tlckTRUNCATE: * free child extents covered by parent [); */ tlck = txLock(tid, ip, mp, tlckXTREE); xtlck = (struct xtlock *) & tlck->lock; if (!(tlck->type & tlckTRUNCATE)) { xtlck->hwm.offset = le16_to_cpu(p->header. nextindex) - 1; tlck->type = tlckXTREE | tlckTRUNCATE; } } else { /* COMMIT_WMAP */ /* free child extents covered by parent */ xadlock.xdlist = &p->xad[index + 1]; xadlock.count = le16_to_cpu(p->header.nextindex) - index - 1; txFreeMap(ip, (struct maplock *) & xadlock, NULL, COMMIT_WMAP); } BT_MARK_DIRTY(mp, ip); p->header.nextindex = cpu_to_le16(index + 1); } XT_PUTPAGE(mp); goto getParent; } /* * child page was empty: */ nfreed += lengthXAD(&p->xad[index]); /* * During working map update, child page's tlock must be handled * before parent's. This is because the parent's tlock will cause * the child's disk space to be marked available in the wmap, so * it's important that the child page be released by that time. * * ToDo: tlocks should be on doubly-linked list, so we can * quickly remove it and add it to the end. */ /* * Move parent page's tlock to the end of the tid's tlock list */ if (log && mp->lid && (tblk->last != mp->lid) && lid_to_tlock(mp->lid)->tid) { lid_t lid = mp->lid; struct tlock *prev; tlck = lid_to_tlock(lid); if (tblk->next == lid) tblk->next = tlck->next; else { for (prev = lid_to_tlock(tblk->next); prev->next != lid; prev = lid_to_tlock(prev->next)) { assert(prev->next); } prev->next = tlck->next; } lid_to_tlock(tblk->last)->next = lid; tlck->next = 0; tblk->last = lid; } /* * parent page become empty: free the page */ if (index == XTENTRYSTART) { if (log) { /* COMMIT_PWMAP */ /* txCommit() with tlckFREE: * free child extents covered by parent; * invalidate parent if COMMIT_PWMAP; */ tlck = txLock(tid, ip, mp, tlckXTREE); xtlck = (struct xtlock *) & tlck->lock; xtlck->hwm.offset = le16_to_cpu(p->header.nextindex) - 1; tlck->type = tlckXTREE | tlckFREE; } else { /* COMMIT_WMAP */ /* free child extents covered by parent */ xadlock.xdlist = &p->xad[XTENTRYSTART]; xadlock.count = le16_to_cpu(p->header.nextindex) - XTENTRYSTART; txFreeMap(ip, (struct maplock *) & xadlock, NULL, COMMIT_WMAP); } BT_MARK_DIRTY(mp, ip); if (p->header.flag & BT_ROOT) { p->header.flag &= ~BT_INTERNAL; p->header.flag |= BT_LEAF; p->header.nextindex = cpu_to_le16(XTENTRYSTART); if (le16_to_cpu(p->header.maxentry) == XTROOTMAXSLOT) { /* * Shrink root down to allow inline * EA (otherwise fsck complains) */ p->header.maxentry = cpu_to_le16(XTROOTINITSLOT); JFS_IP(ip)->mode2 |= INLINEEA; } XT_PUTPAGE(mp); /* debug */ goto out; } else { if (log) { /* COMMIT_PWMAP */ /* page will be invalidated at tx completion */ XT_PUTPAGE(mp); } else { /* COMMIT_WMAP */ if (mp->lid) lid_to_tlock(mp->lid)->flag |= tlckFREELOCK; /* invalidate parent page */ discard_metapage(mp); } /* parent has become empty and freed: * go back up to its parent page */ /* freed = 1; */ goto getParent; } } /* * parent page still has entries for front region; */ else { /* try truncate region covered by preceding entry * (process backward) */ index--; /* go back down to the child page corresponding * to the entry */ goto getChild; } /* * internal page: go down to child page of current entry */ getChild: /* save current parent entry for the child page */ if (BT_STACK_FULL(&btstack)) { jfs_error(ip->i_sb, "stack overrun in xtTruncate!"); XT_PUTPAGE(mp); return -EIO; } BT_PUSH(&btstack, bn, index); /* get child page */ xad = &p->xad[index]; bn = addressXAD(xad); /* * first access of each internal entry: */ /* release parent page */ XT_PUTPAGE(mp); /* process the child page */ goto getPage; out: /* * update file resource stat */ /* set size */ if (S_ISDIR(ip->i_mode) && !newsize) ip->i_size = 1; /* fsck hates zero-length directories */ else ip->i_size = newsize; /* update quota allocation to reflect freed blocks */ vfs_dq_free_block(ip, nfreed); /* * free tlock of invalidated pages */ if (flag == COMMIT_WMAP) txFreelock(ip); return newsize; } /* * xtTruncate_pmap() * * function: * Perform truncate to zero length for deleted file, leaving the * the xtree and working map untouched. This allows the file to * be accessed via open file handles, while the delete of the file * is committed to disk. * * parameter: * tid_t tid, * struct inode *ip, * s64 committed_size) * * return: new committed size * * note: * * To avoid deadlock by holding too many transaction locks, the * truncation may be broken up into multiple transactions. * The committed_size keeps track of part of the file has been * freed from the pmaps. */ s64 xtTruncate_pmap(tid_t tid, struct inode *ip, s64 committed_size) { s64 bn; struct btstack btstack; int cmp; int index; int locked_leaves = 0; struct metapage *mp; xtpage_t *p; struct btframe *parent; int rc; struct tblock *tblk; struct tlock *tlck = NULL; xad_t *xad; int xlen; s64 xoff; struct xtlock *xtlck = NULL; /* save object truncation type */ tblk = tid_to_tblock(tid); tblk->xflag |= COMMIT_PMAP; /* clear stack */ BT_CLR(&btstack); if (committed_size) { xoff = (committed_size >> JFS_SBI(ip->i_sb)->l2bsize) - 1; rc = xtSearch(ip, xoff, NULL, &cmp, &btstack, 0); if (rc) return rc; XT_GETSEARCH(ip, btstack.top, bn, mp, p, index); if (cmp != 0) { XT_PUTPAGE(mp); jfs_error(ip->i_sb, "xtTruncate_pmap: did not find extent"); return -EIO; } } else { /* * start with root * * root resides in the inode */ bn = 0; /* * first access of each page: */ getPage: XT_GETPAGE(ip, bn, mp, PSIZE, p, rc); if (rc) return rc; /* process entries backward from last index */ index = le16_to_cpu(p->header.nextindex) - 1; if (p->header.flag & BT_INTERNAL) goto getChild; } /* * leaf page */ if (++locked_leaves > MAX_TRUNCATE_LEAVES) { /* * We need to limit the size of the transaction * to avoid exhausting pagecache & tlocks */ xad = &p->xad[index]; xoff = offsetXAD(xad); xlen = lengthXAD(xad); XT_PUTPAGE(mp); return (xoff + xlen) << JFS_SBI(ip->i_sb)->l2bsize; } tlck = txLock(tid, ip, mp, tlckXTREE); tlck->type = tlckXTREE | tlckFREE; xtlck = (struct xtlock *) & tlck->lock; xtlck->hwm.offset = index; XT_PUTPAGE(mp); /* * go back up to the parent page */ getParent: /* pop/restore parent entry for the current child page */ if ((parent = BT_POP(&btstack)) == NULL) /* current page must have been root */ goto out; /* get back the parent page */ bn = parent->bn; XT_GETPAGE(ip, bn, mp, PSIZE, p, rc); if (rc) return rc; index = parent->index; /* * parent page become empty: free the page */ if (index == XTENTRYSTART) { /* txCommit() with tlckFREE: * free child extents covered by parent; * invalidate parent if COMMIT_PWMAP; */ tlck = txLock(tid, ip, mp, tlckXTREE); xtlck = (struct xtlock *) & tlck->lock; xtlck->hwm.offset = le16_to_cpu(p->header.nextindex) - 1; tlck->type = tlckXTREE | tlckFREE; XT_PUTPAGE(mp); if (p->header.flag & BT_ROOT) { goto out; } else { goto getParent; } } /* * parent page still has entries for front region; */ else index--; /* * internal page: go down to child page of current entry */ getChild: /* save current parent entry for the child page */ if (BT_STACK_FULL(&btstack)) { jfs_error(ip->i_sb, "stack overrun in xtTruncate_pmap!"); XT_PUTPAGE(mp); return -EIO; } BT_PUSH(&btstack, bn, index); /* get child page */ xad = &p->xad[index]; bn = addressXAD(xad); /* * first access of each internal entry: */ /* release parent page */ XT_PUTPAGE(mp); /* process the child page */ goto getPage; out: return 0; } #ifdef CONFIG_JFS_STATISTICS static int jfs_xtstat_proc_show(struct seq_file *m, void *v) { seq_printf(m, "JFS Xtree statistics\n" "====================\n" "searches = %d\n" "fast searches = %d\n" "splits = %d\n", xtStat.search, xtStat.fastSearch, xtStat.split); return 0; } static int jfs_xtstat_proc_open(struct inode *inode, struct file *file) { return single_open(file, jfs_xtstat_proc_show, NULL); } const struct file_operations jfs_xtstat_proc_fops = { .owner = THIS_MODULE, .open = jfs_xtstat_proc_open, .read = seq_read, .llseek = seq_lseek, .release = single_release, }; #endif