Merge branch 'master' of /home/tglx/work/kernel/git/mtd-2.6/
[powerpc.git] / fs / jffs2 / wbuf.c
index c7e3040..916c87d 100644 (file)
@@ -613,20 +613,30 @@ int jffs2_flush_wbuf_pad(struct jffs2_sb_info *c)
 
        return ret;
 }
-int jffs2_flash_writev(struct jffs2_sb_info *c, const struct kvec *invecs, unsigned long count, loff_t to, size_t *retlen, uint32_t ino)
+
+static size_t jffs2_fill_wbuf(struct jffs2_sb_info *c, const uint8_t *buf,
+                             size_t len)
+{
+       if (len && !c->wbuf_len && (len >= c->wbuf_pagesize))
+               return 0;
+
+       if (len > (c->wbuf_pagesize - c->wbuf_len))
+               len = c->wbuf_pagesize - c->wbuf_len;
+       memcpy(c->wbuf + c->wbuf_len, buf, len);
+       c->wbuf_len += (uint32_t) len;
+       return len;
+}
+
+int jffs2_flash_writev(struct jffs2_sb_info *c, const struct kvec *invecs,
+                      unsigned long count, loff_t to, size_t *retlen,
+                      uint32_t ino)
 {
-       struct kvec outvecs[3];
-       uint32_t totlen = 0;
-       uint32_t split_ofs = 0;
-       uint32_t old_totlen;
-       int ret, splitvec = -1;
-       int invec, outvec;
-       size_t wbuf_retlen;
-       unsigned char *wbuf_ptr;
-       size_t donelen = 0;
+       struct jffs2_eraseblock *jeb;
+       size_t wbuf_retlen, donelen = 0;
        uint32_t outvec_to = to;
+       int ret, invec;
 
-       /* If not NAND flash, don't bother */
+       /* If not writebuffered flash, don't bother */
        if (!jffs2_is_writebuffered(c))
                return jffs2_flash_direct_writev(c, invecs, count, to, retlen);
 
@@ -639,23 +649,22 @@ int jffs2_flash_writev(struct jffs2_sb_info *c, const struct kvec *invecs, unsig
                memset(c->wbuf,0xff,c->wbuf_pagesize);
        }
 
-       /* Sanity checks on target address.
-          It's permitted to write at PAD(c->wbuf_len+c->wbuf_ofs),
-          and it's permitted to write at the beginning of a new
-          erase block. Anything else, and you die.
-          New block starts at xxx000c (0-b = block header)
-       */
+       /*
+        * Sanity checks on target address.  It's permitted to write
+        * at PAD(c->wbuf_len+c->wbuf_ofs), and it's permitted to
+        * write at the beginning of a new erase block. Anything else,
+        * and you die.  New block starts at xxx000c (0-b = block
+        * header)
+        */
        if (SECTOR_ADDR(to) != SECTOR_ADDR(c->wbuf_ofs)) {
                /* It's a write to a new block */
                if (c->wbuf_len) {
-                       D1(printk(KERN_DEBUG "jffs2_flash_writev() to 0x%lx causes flush of wbuf at 0x%08x\n", (unsigned long)to, c->wbuf_ofs));
+                       D1(printk(KERN_DEBUG "jffs2_flash_writev() to 0x%lx "
+                                 "causes flush of wbuf at 0x%08x\n",
+                                 (unsigned long)to, c->wbuf_ofs));
                        ret = __jffs2_flush_wbuf(c, PAD_NOACCOUNT);
-                       if (ret) {
-                               /* the underlying layer has to check wbuf_len to do the cleanup */
-                               D1(printk(KERN_WARNING "jffs2_flush_wbuf() called from jffs2_flash_writev() failed %d\n", ret));
-                               *retlen = 0;
-                               goto exit;
-                       }
+                       if (ret)
+                               goto outerr;
                }
                /* set pointer to new block */
                c->wbuf_ofs = PAGE_DIV(to);
@@ -664,165 +673,70 @@ int jffs2_flash_writev(struct jffs2_sb_info *c, const struct kvec *invecs, unsig
 
        if (to != PAD(c->wbuf_ofs + c->wbuf_len)) {
                /* We're not writing immediately after the writebuffer. Bad. */
-               printk(KERN_CRIT "jffs2_flash_writev(): Non-contiguous write to %08lx\n", (unsigned long)to);
+               printk(KERN_CRIT "jffs2_flash_writev(): Non-contiguous write "
+                      "to %08lx\n", (unsigned long)to);
                if (c->wbuf_len)
                        printk(KERN_CRIT "wbuf was previously %08x-%08x\n",
-                                         c->wbuf_ofs, c->wbuf_ofs+c->wbuf_len);
-               BUG();
-       }
-
-       /* Note outvecs[3] above. We know count is never greater than 2 */
-       if (count > 2) {
-               printk(KERN_CRIT "jffs2_flash_writev(): count is %ld\n", count);
+                              c->wbuf_ofs, c->wbuf_ofs+c->wbuf_len);
                BUG();
        }
 
-       invec = 0;
-       outvec = 0;
-
-       /* Fill writebuffer first, if already in use */
-       if (c->wbuf_len) {
-               uint32_t invec_ofs = 0;
-
-               /* adjust alignment offset */
-               if (c->wbuf_len != PAGE_MOD(to)) {
-                       c->wbuf_len = PAGE_MOD(to);
-                       /* take care of alignment to next page */
-                       if (!c->wbuf_len)
-                               c->wbuf_len = c->wbuf_pagesize;
-               }
-
-               while(c->wbuf_len < c->wbuf_pagesize) {
-                       uint32_t thislen;
-
-                       if (invec == count)
-                               goto alldone;
-
-                       thislen = c->wbuf_pagesize - c->wbuf_len;
-
-                       if (thislen >= invecs[invec].iov_len)
-                               thislen = invecs[invec].iov_len;
-
-                       invec_ofs = thislen;
-
-                       memcpy(c->wbuf + c->wbuf_len, invecs[invec].iov_base, thislen);
-                       c->wbuf_len += thislen;
-                       donelen += thislen;
-                       /* Get next invec, if actual did not fill the buffer */
-                       if (c->wbuf_len < c->wbuf_pagesize)
-                               invec++;
-               }
-
-               /* write buffer is full, flush buffer */
-               ret = __jffs2_flush_wbuf(c, NOPAD);
-               if (ret) {
-                       /* the underlying layer has to check wbuf_len to do the cleanup */
-                       D1(printk(KERN_WARNING "jffs2_flush_wbuf() called from jffs2_flash_writev() failed %d\n", ret));
-                       /* Retlen zero to make sure our caller doesn't mark the space dirty.
-                          We've already done everything that's necessary */
-                       *retlen = 0;
-                       goto exit;
-               }
-               outvec_to += donelen;
-               c->wbuf_ofs = outvec_to;
-
-               /* All invecs done ? */
-               if (invec == count)
-                       goto alldone;
-
-               /* Set up the first outvec, containing the remainder of the
-                  invec we partially used */
-               if (invecs[invec].iov_len > invec_ofs) {
-                       outvecs[0].iov_base = invecs[invec].iov_base+invec_ofs;
-                       totlen = outvecs[0].iov_len = invecs[invec].iov_len-invec_ofs;
-                       if (totlen > c->wbuf_pagesize) {
-                               splitvec = outvec;
-                               split_ofs = outvecs[0].iov_len - PAGE_MOD(totlen);
-                       }
-                       outvec++;
-               }
-               invec++;
-       }
-
-       /* OK, now we've flushed the wbuf and the start of the bits
-          we have been asked to write, now to write the rest.... */
-
-       /* totlen holds the amount of data still to be written */
-       old_totlen = totlen;
-       for ( ; invec < count; invec++,outvec++ ) {
-               outvecs[outvec].iov_base = invecs[invec].iov_base;
-               totlen += outvecs[outvec].iov_len = invecs[invec].iov_len;
-               if (PAGE_DIV(totlen) != PAGE_DIV(old_totlen)) {
-                       splitvec = outvec;
-                       split_ofs = outvecs[outvec].iov_len - PAGE_MOD(totlen);
-                       old_totlen = totlen;
+       /* adjust alignment offset */
+       if (c->wbuf_len != PAGE_MOD(to)) {
+               c->wbuf_len = PAGE_MOD(to);
+               /* take care of alignment to next page */
+               if (!c->wbuf_len) {
+                       c->wbuf_len = c->wbuf_pagesize;
+                       ret = __jffs2_flush_wbuf(c, NOPAD);
+                       if (ret)
+                               goto outerr;
                }
        }
 
-       /* Now the outvecs array holds all the remaining data to write */
-       /* Up to splitvec,split_ofs is to be written immediately. The rest
-          goes into the (now-empty) wbuf */
-
-       if (splitvec != -1) {
-               uint32_t remainder;
-
-               remainder = outvecs[splitvec].iov_len - split_ofs;
-               outvecs[splitvec].iov_len = split_ofs;
-
-               /* We did cross a page boundary, so we write some now */
-               if (jffs2_cleanmarker_oob(c))
-                       ret = c->mtd->writev_ecc(c->mtd, outvecs, splitvec+1, outvec_to, &wbuf_retlen, NULL, c->oobinfo);
-               else
-                       ret = jffs2_flash_direct_writev(c, outvecs, splitvec+1, outvec_to, &wbuf_retlen);
-
-               if (ret < 0 || wbuf_retlen != PAGE_DIV(totlen)) {
-                       /* At this point we have no problem,
-                          c->wbuf is empty. However refile nextblock to avoid
-                          writing again to same address.
-                       */
-                       struct jffs2_eraseblock *jeb;
-
-                       spin_lock(&c->erase_completion_lock);
+       for (invec = 0; invec < count; invec++) {
+               int vlen = invecs[invec].iov_len;
+               uint8_t *v = invecs[invec].iov_base;
 
-                       jeb = &c->blocks[outvec_to / c->sector_size];
-                       jffs2_block_refile(c, jeb, REFILE_ANYWAY);
+               wbuf_retlen = jffs2_fill_wbuf(c, v, vlen);
 
-                       *retlen = 0;
-                       spin_unlock(&c->erase_completion_lock);
-                       goto exit;
+               if (c->wbuf_len == c->wbuf_pagesize) {
+                       ret = __jffs2_flush_wbuf(c, NOPAD);
+                       if (ret)
+                               goto outerr;
                }
-
+               vlen -= wbuf_retlen;
+               outvec_to += wbuf_retlen;
                donelen += wbuf_retlen;
-               c->wbuf_ofs = PAGE_DIV(outvec_to) + PAGE_DIV(totlen);
-
-               if (remainder) {
-                       outvecs[splitvec].iov_base += split_ofs;
-                       outvecs[splitvec].iov_len = remainder;
-               } else {
-                       splitvec++;
+               v += wbuf_retlen;
+
+               if (vlen >= c->wbuf_pagesize) {
+                       ret = c->mtd->write(c->mtd, outvec_to, PAGE_DIV(vlen),
+                                           &wbuf_retlen, v);
+                       if (ret < 0 || wbuf_retlen != PAGE_DIV(vlen))
+                               goto outfile;
+
+                       vlen -= wbuf_retlen;
+                       outvec_to += wbuf_retlen;
+                       c->wbuf_ofs = outvec_to;
+                       donelen += wbuf_retlen;
+                       v += wbuf_retlen;
                }
 
-       } else {
-               splitvec = 0;
-       }
-
-       /* Now splitvec points to the start of the bits we have to copy
-          into the wbuf */
-       wbuf_ptr = c->wbuf;
+               wbuf_retlen = jffs2_fill_wbuf(c, v, vlen);
+               if (c->wbuf_len == c->wbuf_pagesize) {
+                       ret = __jffs2_flush_wbuf(c, NOPAD);
+                       if (ret)
+                               goto outerr;
+               }
 
-       for ( ; splitvec < outvec; splitvec++) {
-               /* Don't copy the wbuf into itself */
-               if (outvecs[splitvec].iov_base == c->wbuf)
-                       continue;
-               memcpy(wbuf_ptr, outvecs[splitvec].iov_base, outvecs[splitvec].iov_len);
-               wbuf_ptr += outvecs[splitvec].iov_len;
-               donelen += outvecs[splitvec].iov_len;
+               outvec_to += wbuf_retlen;
+               donelen += wbuf_retlen;
        }
-       c->wbuf_len = wbuf_ptr - c->wbuf;
 
-       /* If there's a remainder in the wbuf and it's a non-GC write,
-          remember that the wbuf affects this ino */
-alldone:
+       /*
+        * If there's a remainder in the wbuf and it's a non-GC write,
+        * remember that the wbuf affects this ino
+        */
        *retlen = donelen;
 
        if (jffs2_sum_active()) {
@@ -835,8 +749,24 @@ alldone:
                jffs2_wbuf_dirties_inode(c, ino);
 
        ret = 0;
+       up_write(&c->wbuf_sem);
+       return ret;
 
-exit:
+outfile:
+       /*
+        * At this point we have no problem, c->wbuf is empty. However
+        * refile nextblock to avoid writing again to same address.
+        */
+
+       spin_lock(&c->erase_completion_lock);
+
+       jeb = &c->blocks[outvec_to / c->sector_size];
+       jffs2_block_refile(c, jeb, REFILE_ANYWAY);
+
+       spin_unlock(&c->erase_completion_lock);
+
+outerr:
+       *retlen = 0;
        up_write(&c->wbuf_sem);
        return ret;
 }