jfs: remove xtLookupList()
xtLookupList() was a more generalized version of xtLookup() with a nastier interface. Its only caller, extHint(), is actually better suited to using xtLookup() than xtLookupList(). This also lets us remove the definition of lxd_t, an obnoxious packed structure that was only used in-memory. Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
This commit is contained in:
Dave Kleikamp
@@ -164,11 +164,8 @@ int xtLookup(struct inode *ip, s64 lstart,
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/* is lookup offset beyond eof ? */
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size = ((u64) ip->i_size + (JFS_SBI(ip->i_sb)->bsize - 1)) >>
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JFS_SBI(ip->i_sb)->l2bsize;
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if (lstart >= size) {
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jfs_err("xtLookup: lstart (0x%lx) >= size (0x%lx)",
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(ulong) lstart, (ulong) size);
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if (lstart >= size)
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return 0;
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}
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}
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/*
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@@ -220,264 +217,6 @@ int xtLookup(struct inode *ip, s64 lstart,
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return rc;
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}
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/*
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* xtLookupList()
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*
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* function: map a single logical extent into a list of physical extent;
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*
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* parameter:
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* struct inode *ip,
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* struct lxdlist *lxdlist, lxd list (in)
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* struct xadlist *xadlist, xad list (in/out)
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* int flag)
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*
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* coverage of lxd by xad under assumption of
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* . lxd's are ordered and disjoint.
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* . xad's are ordered and disjoint.
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*
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* return:
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* 0: success
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*
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* note: a page being written (even a single byte) is backed fully,
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* except the last page which is only backed with blocks
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* required to cover the last byte;
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* the extent backing a page is fully contained within an xad;
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*/
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int xtLookupList(struct inode *ip, struct lxdlist * lxdlist,
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struct xadlist * xadlist, int flag)
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{
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int rc = 0;
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struct btstack btstack;
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int cmp;
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s64 bn;
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struct metapage *mp;
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xtpage_t *p;
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int index;
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lxd_t *lxd;
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xad_t *xad, *pxd;
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s64 size, lstart, lend, xstart, xend, pstart;
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s64 llen, xlen, plen;
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s64 xaddr, paddr;
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int nlxd, npxd, maxnpxd;
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npxd = xadlist->nxad = 0;
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maxnpxd = xadlist->maxnxad;
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pxd = xadlist->xad;
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nlxd = lxdlist->nlxd;
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lxd = lxdlist->lxd;
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lstart = offsetLXD(lxd);
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llen = lengthLXD(lxd);
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lend = lstart + llen;
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size = (ip->i_size + (JFS_SBI(ip->i_sb)->bsize - 1)) >>
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JFS_SBI(ip->i_sb)->l2bsize;
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/*
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* search for the xad entry covering the logical extent
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*/
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search:
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if (lstart >= size)
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return 0;
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if ((rc = xtSearch(ip, lstart, NULL, &cmp, &btstack, 0)))
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return rc;
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/*
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* compute the physical extent covering logical extent
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*
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* N.B. search may have failed (e.g., hole in sparse file),
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* and returned the index of the next entry.
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*/
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//map:
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/* retrieve search result */
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XT_GETSEARCH(ip, btstack.top, bn, mp, p, index);
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/* is xad on the next sibling page ? */
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if (index == le16_to_cpu(p->header.nextindex)) {
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if (p->header.flag & BT_ROOT)
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goto mapend;
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if ((bn = le64_to_cpu(p->header.next)) == 0)
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goto mapend;
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XT_PUTPAGE(mp);
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/* get next sibling page */
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XT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
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if (rc)
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return rc;
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index = XTENTRYSTART;
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}
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xad = &p->xad[index];
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/*
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* is lxd covered by xad ?
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*/
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compare:
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xstart = offsetXAD(xad);
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xlen = lengthXAD(xad);
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xend = xstart + xlen;
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xaddr = addressXAD(xad);
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compare1:
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if (xstart < lstart)
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goto compare2;
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/* (lstart <= xstart) */
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/* lxd is NOT covered by xad */
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if (lend <= xstart) {
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/*
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* get next lxd
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*/
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if (--nlxd == 0)
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goto mapend;
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lxd++;
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lstart = offsetLXD(lxd);
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llen = lengthLXD(lxd);
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lend = lstart + llen;
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if (lstart >= size)
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goto mapend;
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/* compare with the current xad */
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goto compare1;
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}
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/* lxd is covered by xad */
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else { /* (xstart < lend) */
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/* initialize new pxd */
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pstart = xstart;
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plen = min(lend - xstart, xlen);
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paddr = xaddr;
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goto cover;
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}
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/* (xstart < lstart) */
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compare2:
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/* lxd is covered by xad */
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if (lstart < xend) {
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/* initialize new pxd */
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pstart = lstart;
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plen = min(xend - lstart, llen);
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paddr = xaddr + (lstart - xstart);
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goto cover;
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}
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/* lxd is NOT covered by xad */
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else { /* (xend <= lstart) */
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/*
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* get next xad
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*
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* linear search next xad covering lxd on
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* the current xad page, and then tree search
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*/
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if (index == le16_to_cpu(p->header.nextindex) - 1) {
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if (p->header.flag & BT_ROOT)
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goto mapend;
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XT_PUTPAGE(mp);
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goto search;
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} else {
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index++;
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xad++;
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/* compare with new xad */
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goto compare;
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}
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}
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/*
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* lxd is covered by xad and a new pxd has been initialized
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* (lstart <= xstart < lend) or (xstart < lstart < xend)
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*/
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cover:
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/* finalize pxd corresponding to current xad */
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XT_PUTENTRY(pxd, xad->flag, pstart, plen, paddr);
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if (++npxd >= maxnpxd)
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goto mapend;
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pxd++;
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/*
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* lxd is fully covered by xad
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*/
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if (lend <= xend) {
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/*
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* get next lxd
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*/
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if (--nlxd == 0)
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goto mapend;
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lxd++;
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lstart = offsetLXD(lxd);
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llen = lengthLXD(lxd);
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lend = lstart + llen;
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if (lstart >= size)
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goto mapend;
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/*
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* test for old xad covering new lxd
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* (old xstart < new lstart)
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*/
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goto compare2;
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}
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/*
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* lxd is partially covered by xad
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*/
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else { /* (xend < lend) */
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/*
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* get next xad
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*
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* linear search next xad covering lxd on
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* the current xad page, and then next xad page search
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*/
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if (index == le16_to_cpu(p->header.nextindex) - 1) {
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if (p->header.flag & BT_ROOT)
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goto mapend;
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if ((bn = le64_to_cpu(p->header.next)) == 0)
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goto mapend;
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XT_PUTPAGE(mp);
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/* get next sibling page */
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XT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
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if (rc)
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return rc;
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index = XTENTRYSTART;
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xad = &p->xad[index];
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} else {
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index++;
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xad++;
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}
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/*
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* test for new xad covering old lxd
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* (old lstart < new xstart)
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*/
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goto compare;
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}
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mapend:
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xadlist->nxad = npxd;
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//out:
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XT_PUTPAGE(mp);
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return rc;
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}
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/*
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* xtSearch()
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*
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