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>

4 files changed, 25 insertions, 332 deletions

diff --git a/fs/jfs/jfs_extent.c b/fs/jfs/jfs_extent.c
index 7ae1e3281de9..16bc326eeca4 100644
--- a/fs/jfs/jfs_extent.c
+++ b/fs/jfs/jfs_extent.c
@@ -362,11 +362,12 @@ exit:
 int extHint(struct inode *ip, s64 offset, xad_t * xp)
 {
         struct super_block *sb = ip->i_sb;
-        struct xadlist xadl;
-        struct lxdlist lxdl;
-        lxd_t lxd;
+        int nbperpage = JFS_SBI(sb)->nbperpage;
         s64 prev;
-        int rc, nbperpage = JFS_SBI(sb)->nbperpage;
+        int rc = 0;
+        s64 xaddr;
+        int xlen;
+        int xflag;
 
         /* init the hint as "no hint provided" */
         XADaddress(xp, 0);
@@ -376,46 +377,30 @@ int extHint(struct inode *ip, s64 offset, xad_t * xp)
          */
         prev = ((offset & ~POFFSET) >> JFS_SBI(sb)->l2bsize) - nbperpage;
 
-        /* if the offsets in the first page of the file,
-         * no hint provided.
+        /* if the offset is in the first page of the file, no hint provided.
          */
         if (prev < 0)
-                return (0);
-
-        /* prepare to lookup the previous page's extent info */
-        lxdl.maxnlxd = 1;
-        lxdl.nlxd = 1;
-        lxdl.lxd = &lxd;
-        LXDoffset(&lxd, prev)
-        LXDlength(&lxd, nbperpage);
-
-        xadl.maxnxad = 1;
-        xadl.nxad = 0;
-        xadl.xad = xp;
-
-        /* perform the lookup */
-        if ((rc = xtLookupList(ip, &lxdl, &xadl, 0)))
-                return (rc);
-
-        /* check if no extent exists for the previous page.
-         * this is possible for sparse files.
-         */
-        if (xadl.nxad == 0) {
-//              assert(ISSPARSE(ip));
-                return (0);
-        }
+                goto out;
 
-        /* only preserve the abnr flag within the xad flags
-         * of the returned hint.
-         */
-        xp->flag &= XAD_NOTRECORDED;
+        rc = xtLookup(ip, prev, nbperpage, &xflag, &xaddr, &xlen, 0);
 
-        if(xadl.nxad != 1 || lengthXAD(xp) != nbperpage) {
-                jfs_error(ip->i_sb, "extHint: corrupt xtree");
-                return -EIO;
-        }
+        if ((rc == 0) && xlen) {
+                if (xlen != nbperpage) {
+                        jfs_error(ip->i_sb, "extHint: corrupt xtree");
+                        rc = -EIO;
+                }
+                XADaddress(xp, xaddr);
+                XADlength(xp, xlen);
+                /*
+                 * only preserve the abnr flag within the xad flags
+                 * of the returned hint.
+                 */
+                xp->flag  = xflag & XAD_NOTRECORDED;
+        } else
+                rc = 0;
 
-        return (0);
+out:
+        return (rc);
 }
 
 
diff --git a/fs/jfs/jfs_types.h b/fs/jfs/jfs_types.h
index 649f9817accd..43ea3713c083 100644
--- a/fs/jfs/jfs_types.h
+++ b/fs/jfs/jfs_types.h
@@ -58,35 +58,6 @@ struct timestruc_t {
 #define ONES            0xffffffffu     /* all bit on           */
 
 /*
- *      logical xd (lxd)
- */
-typedef struct {
-        unsigned len:24;
-        unsigned off1:8;
-        u32 off2;
-} lxd_t;
-
-/* lxd_t field construction */
-#define LXDlength(lxd, length32)        ( (lxd)->len = length32 )
-#define LXDoffset(lxd, offset64)\
-{\
-        (lxd)->off1 = ((s64)offset64) >> 32;\
-        (lxd)->off2 = (offset64) & 0xffffffff;\
-}
-
-/* lxd_t field extraction */
-#define lengthLXD(lxd)  ( (lxd)->len )
-#define offsetLXD(lxd)\
-        ( ((s64)((lxd)->off1)) << 32 | (lxd)->off2 )
-
-/* lxd list */
-struct lxdlist {
-        s16 maxnlxd;
-        s16 nlxd;
-        lxd_t *lxd;
-};
-
-/*
  *      physical xd (pxd)
  */
 typedef struct {
diff --git a/fs/jfs/jfs_xtree.c b/fs/jfs/jfs_xtree.c
index ae3acafb447b..44380fb0d7c2 100644
--- a/fs/jfs/jfs_xtree.c
+++ b/fs/jfs/jfs_xtree.c
@@ -164,11 +164,8 @@ int xtLookup(struct inode *ip, s64 lstart,
                 /* 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) {
-                        jfs_err("xtLookup: lstart (0x%lx) >= size (0x%lx)",
-                                (ulong) lstart, (ulong) size);
+                if (lstart >= size)
                         return 0;
-                }
         }
 
         /*
@@ -220,264 +217,6 @@ int xtLookup(struct inode *ip, s64 lstart,
         return rc;
 }
 
-
-/*
- *      xtLookupList()
- *
- * function: map a single logical extent into a list of physical extent;
- *
- * parameter:
- *      struct inode    *ip,
- *      struct lxdlist  *lxdlist,       lxd list (in)
- *      struct xadlist  *xadlist,       xad list (in/out)
- *      int             flag)
- *
- * coverage of lxd by xad under assumption of
- * . lxd's are ordered and disjoint.
- * . xad's are ordered and disjoint.
- *
- * return:
- *      0:      success
- *
- * note: a page being written (even a single byte) is backed fully,
- *      except the last page which is only backed with blocks
- *      required to cover the last byte;
- *      the extent backing a page is fully contained within an xad;
- */
-int xtLookupList(struct inode *ip, struct lxdlist * lxdlist,
-                 struct xadlist * xadlist, int flag)
-{
-        int rc = 0;
-        struct btstack btstack;
-        int cmp;
-        s64 bn;
-        struct metapage *mp;
-        xtpage_t *p;
-        int index;
-        lxd_t *lxd;
-        xad_t *xad, *pxd;
-        s64 size, lstart, lend, xstart, xend, pstart;
-        s64 llen, xlen, plen;
-        s64 xaddr, paddr;
-        int nlxd, npxd, maxnpxd;
-
-        npxd = xadlist->nxad = 0;
-        maxnpxd = xadlist->maxnxad;
-        pxd = xadlist->xad;
-
-        nlxd = lxdlist->nlxd;
-        lxd = lxdlist->lxd;
-
-        lstart = offsetLXD(lxd);
-        llen = lengthLXD(lxd);
-        lend = lstart + llen;
-
-        size = (ip->i_size + (JFS_SBI(ip->i_sb)->bsize - 1)) >>
-            JFS_SBI(ip->i_sb)->l2bsize;
-
-        /*
-         * search for the xad entry covering the logical extent
-         */
-      search:
-        if (lstart >= size)
-                return 0;
-
-        if ((rc = xtSearch(ip, lstart, NULL, &cmp, &btstack, 0)))
-                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.
-         */
-//map:
-        /* retrieve search result */
-        XT_GETSEARCH(ip, btstack.top, bn, mp, p, index);
-
-        /* is xad on the next sibling page ? */
-        if (index == le16_to_cpu(p->header.nextindex)) {
-                if (p->header.flag & BT_ROOT)
-                        goto mapend;
-
-                if ((bn = le64_to_cpu(p->header.next)) == 0)
-                        goto mapend;
-
-                XT_PUTPAGE(mp);
-
-                /* get next sibling page */
-                XT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
-                if (rc)
-                        return rc;
-
-                index = XTENTRYSTART;
-        }
-
-        xad = &p->xad[index];
-
-        /*
-         * is lxd covered by xad ?
-         */
-      compare:
-        xstart = offsetXAD(xad);
-        xlen = lengthXAD(xad);
-        xend = xstart + xlen;
-        xaddr = addressXAD(xad);
-
-      compare1:
-        if (xstart < lstart)
-                goto compare2;
-
-        /* (lstart <= xstart) */
-
-        /* lxd is NOT covered by xad */
-        if (lend <= xstart) {
-                /*
-                 * get next lxd
-                 */
-                if (--nlxd == 0)
-                        goto mapend;
-                lxd++;
-
-                lstart = offsetLXD(lxd);
-                llen = lengthLXD(lxd);
-                lend = lstart + llen;
-                if (lstart >= size)
-                        goto mapend;
-
-                /* compare with the current xad */
-                goto compare1;
-        }
-        /* lxd is covered by xad */
-        else {                  /* (xstart < lend) */
-
-                /* initialize new pxd */
-                pstart = xstart;
-                plen = min(lend - xstart, xlen);
-                paddr = xaddr;
-
-                goto cover;
-        }
-
-        /* (xstart < lstart) */
-      compare2:
-        /* lxd is covered by xad */
-        if (lstart < xend) {
-                /* initialize new pxd */
-                pstart = lstart;
-                plen = min(xend - lstart, llen);
-                paddr = xaddr + (lstart - xstart);
-
-                goto cover;
-        }
-        /* lxd is NOT covered by xad */
-        else {                  /* (xend <= lstart) */
-
-                /*
-                 * get next xad
-                 *
-                 * linear search next xad covering lxd on
-                 * the current xad page, and then tree search
-                 */
-                if (index == le16_to_cpu(p->header.nextindex) - 1) {
-                        if (p->header.flag & BT_ROOT)
-                                goto mapend;
-
-                        XT_PUTPAGE(mp);
-                        goto search;
-                } else {
-                        index++;
-                        xad++;
-
-                        /* compare with new xad */
-                        goto compare;
-                }
-        }
-
-        /*
-         * lxd is covered by xad and a new pxd has been initialized
-         * (lstart <= xstart < lend) or (xstart < lstart < xend)
-         */
-      cover:
-        /* finalize pxd corresponding to current xad */
-        XT_PUTENTRY(pxd, xad->flag, pstart, plen, paddr);
-
-        if (++npxd >= maxnpxd)
-                goto mapend;
-        pxd++;
-
-        /*
-         * lxd is fully covered by xad
-         */
-        if (lend <= xend) {
-                /*
-                 * get next lxd
-                 */
-                if (--nlxd == 0)
-                        goto mapend;
-                lxd++;
-
-                lstart = offsetLXD(lxd);
-                llen = lengthLXD(lxd);
-                lend = lstart + llen;
-                if (lstart >= size)
-                        goto mapend;
-
-                /*
-                 * test for old xad covering new lxd
-                 * (old xstart < new lstart)
-                 */
-                goto compare2;
-        }
-        /*
-         * lxd is partially covered by xad
-         */
-        else {                  /* (xend < lend) */
-
-                /*
-                 * get next xad
-                 *
-                 * linear search next xad covering lxd on
-                 * the current xad page, and then next xad page search
-                 */
-                if (index == le16_to_cpu(p->header.nextindex) - 1) {
-                        if (p->header.flag & BT_ROOT)
-                                goto mapend;
-
-                        if ((bn = le64_to_cpu(p->header.next)) == 0)
-                                goto mapend;
-
-                        XT_PUTPAGE(mp);
-
-                        /* get next sibling page */
-                        XT_GETPAGE(ip, bn, mp, PSIZE, p, rc);
-                        if (rc)
-                                return rc;
-
-                        index = XTENTRYSTART;
-                        xad = &p->xad[index];
-                } else {
-                        index++;
-                        xad++;
-                }
-
-                /*
-                 * test for new xad covering old lxd
-                 * (old lstart < new xstart)
-                 */
-                goto compare;
-        }
-
-      mapend:
-        xadlist->nxad = npxd;
-
-//out:
-        XT_PUTPAGE(mp);
-
-        return rc;
-}
-
-
 /*
  *      xtSearch()
  *
diff --git a/fs/jfs/jfs_xtree.h b/fs/jfs/jfs_xtree.h
index 70815c8a3d6a..08c0c749b986 100644
--- a/fs/jfs/jfs_xtree.h
+++ b/fs/jfs/jfs_xtree.h
@@ -110,8 +110,6 @@ typedef union {
  */
 extern int xtLookup(struct inode *ip, s64 lstart, s64 llen,
                     int *pflag, s64 * paddr, int *plen, int flag);
-extern int xtLookupList(struct inode *ip, struct lxdlist * lxdlist,
-                        struct xadlist * xadlist, int flag);
 extern void xtInitRoot(tid_t tid, struct inode *ip);
 extern int xtInsert(tid_t tid, struct inode *ip,
                     int xflag, s64 xoff, int xlen, s64 * xaddrp, int flag);