forked from Minki/linux
fs/adfs: map: use find_next_bit_le() rather than open coding it
Use find_next_bit_le() to find the end of a fragment in the map rather than open-coding this functionality. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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@ -72,50 +72,32 @@ static int lookup_zone(const struct adfs_discmap *dm, const unsigned int idlen,
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const u32 idmask = (1 << idlen) - 1;
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unsigned char *map = dm->dm_bh->b_data;
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unsigned int start = dm->dm_startbit;
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unsigned int mapptr;
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unsigned int fragend;
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u32 frag;
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do {
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frag = GET_FRAG_ID(map, start, idmask);
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mapptr = start + idlen;
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/*
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* find end of fragment
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*/
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{
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__le32 *_map = (__le32 *)map;
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u32 v = le32_to_cpu(_map[mapptr >> 5]) >> (mapptr & 31);
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while (v == 0) {
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mapptr = (mapptr & ~31) + 32;
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if (mapptr >= endbit)
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fragend = find_next_bit_le(map, endbit, start + idlen);
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if (fragend >= endbit)
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goto error;
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v = le32_to_cpu(_map[mapptr >> 5]);
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if (frag == frag_id) {
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unsigned int length = fragend + 1 - start;
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if (*offset < length)
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return start + *offset;
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*offset -= length;
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}
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mapptr += 1 + ffz(~v);
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}
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if (frag == frag_id)
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goto found;
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again:
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start = mapptr;
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} while (mapptr < endbit);
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start = fragend + 1;
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} while (start < endbit);
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return -1;
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error:
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printk(KERN_ERR "adfs: oversized fragment 0x%x at 0x%x-0x%x\n",
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frag, start, mapptr);
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frag, start, fragend);
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return -1;
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found:
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{
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int length = mapptr - start;
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if (*offset >= length) {
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*offset -= length;
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goto again;
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}
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}
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return start + *offset;
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}
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/*
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@ -132,7 +114,7 @@ scan_free_map(struct adfs_sb_info *asb, struct adfs_discmap *dm)
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const unsigned int frag_idlen = idlen <= 15 ? idlen : 15;
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const u32 idmask = (1 << frag_idlen) - 1;
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unsigned char *map = dm->dm_bh->b_data;
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unsigned int start = 8, mapptr;
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unsigned int start = 8, fragend;
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u32 frag;
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unsigned long total = 0;
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@ -151,29 +133,13 @@ scan_free_map(struct adfs_sb_info *asb, struct adfs_discmap *dm)
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do {
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start += frag;
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/*
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* get fragment id
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*/
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frag = GET_FRAG_ID(map, start, idmask);
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mapptr = start + idlen;
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/*
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* find end of fragment
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*/
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{
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__le32 *_map = (__le32 *)map;
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u32 v = le32_to_cpu(_map[mapptr >> 5]) >> (mapptr & 31);
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while (v == 0) {
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mapptr = (mapptr & ~31) + 32;
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if (mapptr >= endbit)
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fragend = find_next_bit_le(map, endbit, start + idlen);
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if (fragend >= endbit)
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goto error;
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v = le32_to_cpu(_map[mapptr >> 5]);
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}
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mapptr += 1 + ffz(~v);
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}
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total += mapptr - start;
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total += fragend + 1 - start;
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} while (frag >= idlen + 1);
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if (frag != 0)
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