diff options
| -rw-r--r-- | fs/hpfs/buffer.c | 96 |
1 files changed, 50 insertions, 46 deletions
diff --git a/fs/hpfs/buffer.c b/fs/hpfs/buffer.c index 4d0a1af..139ef16 100644 --- a/fs/hpfs/buffer.c +++ b/fs/hpfs/buffer.c @@ -86,7 +86,6 @@ void *hpfs_get_sector(struct super_block *s, unsigned secno, struct buffer_head void *hpfs_map_4sectors(struct super_block *s, unsigned secno, struct quad_buffer_head *qbh, int ahead) { - struct buffer_head *bh; char *data; hpfs_lock_assert(s); @@ -100,34 +99,32 @@ void *hpfs_map_4sectors(struct super_block *s, unsigned secno, struct quad_buffe hpfs_prefetch_sectors(s, secno, 4 + ahead); + if (!(qbh->bh[0] = sb_bread(s, secno + 0))) goto bail0; + if (!(qbh->bh[1] = sb_bread(s, secno + 1))) goto bail1; + if (!(qbh->bh[2] = sb_bread(s, secno + 2))) goto bail2; + if (!(qbh->bh[3] = sb_bread(s, secno + 3))) goto bail3; + + if (likely(qbh->bh[1]->b_data == qbh->bh[0]->b_data + 1 * 512) && + likely(qbh->bh[2]->b_data == qbh->bh[0]->b_data + 2 * 512) && + likely(qbh->bh[3]->b_data == qbh->bh[0]->b_data + 3 * 512)) { + return qbh->data = qbh->bh[0]->b_data; + } + qbh->data = data = kmalloc(2048, GFP_NOFS); if (!data) { printk("HPFS: hpfs_map_4sectors: out of memory\n"); - goto bail; + goto bail4; } - qbh->bh[0] = bh = sb_bread(s, secno); - if (!bh) - goto bail0; - memcpy(data, bh->b_data, 512); - - qbh->bh[1] = bh = sb_bread(s, secno + 1); - if (!bh) - goto bail1; - memcpy(data + 512, bh->b_data, 512); - - qbh->bh[2] = bh = sb_bread(s, secno + 2); - if (!bh) - goto bail2; - memcpy(data + 2 * 512, bh->b_data, 512); - - qbh->bh[3] = bh = sb_bread(s, secno + 3); - if (!bh) - goto bail3; - memcpy(data + 3 * 512, bh->b_data, 512); + memcpy(data + 0 * 512, qbh->bh[0]->b_data, 512); + memcpy(data + 1 * 512, qbh->bh[1]->b_data, 512); + memcpy(data + 2 * 512, qbh->bh[2]->b_data, 512); + memcpy(data + 3 * 512, qbh->bh[3]->b_data, 512); return data; + bail4: + brelse(qbh->bh[3]); bail3: brelse(qbh->bh[2]); bail2: @@ -135,9 +132,6 @@ void *hpfs_map_4sectors(struct super_block *s, unsigned secno, struct quad_buffe bail1: brelse(qbh->bh[0]); bail0: - kfree(data); - printk("HPFS: hpfs_map_4sectors: read error\n"); - bail: return NULL; } @@ -155,44 +149,54 @@ void *hpfs_get_4sectors(struct super_block *s, unsigned secno, return NULL; } - /*return hpfs_map_4sectors(s, secno, qbh, 0);*/ + if (!hpfs_get_sector(s, secno + 0, &qbh->bh[0])) goto bail0; + if (!hpfs_get_sector(s, secno + 1, &qbh->bh[1])) goto bail1; + if (!hpfs_get_sector(s, secno + 2, &qbh->bh[2])) goto bail2; + if (!hpfs_get_sector(s, secno + 3, &qbh->bh[3])) goto bail3; + + if (likely(qbh->bh[1]->b_data == qbh->bh[0]->b_data + 1 * 512) && + likely(qbh->bh[2]->b_data == qbh->bh[0]->b_data + 2 * 512) && + likely(qbh->bh[3]->b_data == qbh->bh[0]->b_data + 3 * 512)) { + return qbh->data = qbh->bh[0]->b_data; + } + if (!(qbh->data = kmalloc(2048, GFP_NOFS))) { printk("HPFS: hpfs_get_4sectors: out of memory\n"); - return NULL; + goto bail4; } - if (!(hpfs_get_sector(s, secno, &qbh->bh[0]))) goto bail0; - if (!(hpfs_get_sector(s, secno + 1, &qbh->bh[1]))) goto bail1; - if (!(hpfs_get_sector(s, secno + 2, &qbh->bh[2]))) goto bail2; - if (!(hpfs_get_sector(s, secno + 3, &qbh->bh[3]))) goto bail3; - memcpy(qbh->data, qbh->bh[0]->b_data, 512); - memcpy(qbh->data + 512, qbh->bh[1]->b_data, 512); - memcpy(qbh->data + 2*512, qbh->bh[2]->b_data, 512); - memcpy(qbh->data + 3*512, qbh->bh[3]->b_data, 512); return qbh->data; - bail3: brelse(qbh->bh[2]); - bail2: brelse(qbh->bh[1]); - bail1: brelse(qbh->bh[0]); - bail0: +bail4: + brelse(qbh->bh[3]); +bail3: + brelse(qbh->bh[2]); +bail2: + brelse(qbh->bh[1]); +bail1: + brelse(qbh->bh[0]); +bail0: return NULL; } void hpfs_brelse4(struct quad_buffer_head *qbh) { - brelse(qbh->bh[3]); - brelse(qbh->bh[2]); - brelse(qbh->bh[1]); + if (unlikely(qbh->data != qbh->bh[0]->b_data)) + kfree(qbh->data); brelse(qbh->bh[0]); - kfree(qbh->data); + brelse(qbh->bh[1]); + brelse(qbh->bh[2]); + brelse(qbh->bh[3]); } void hpfs_mark_4buffers_dirty(struct quad_buffer_head *qbh) { - memcpy(qbh->bh[0]->b_data, qbh->data, 512); - memcpy(qbh->bh[1]->b_data, qbh->data + 512, 512); - memcpy(qbh->bh[2]->b_data, qbh->data + 2 * 512, 512); - memcpy(qbh->bh[3]->b_data, qbh->data + 3 * 512, 512); + if (unlikely(qbh->data != qbh->bh[0]->b_data)) { + memcpy(qbh->bh[0]->b_data, qbh->data + 0 * 512, 512); + memcpy(qbh->bh[1]->b_data, qbh->data + 1 * 512, 512); + memcpy(qbh->bh[2]->b_data, qbh->data + 2 * 512, 512); + memcpy(qbh->bh[3]->b_data, qbh->data + 3 * 512, 512); + } mark_buffer_dirty(qbh->bh[0]); mark_buffer_dirty(qbh->bh[1]); mark_buffer_dirty(qbh->bh[2]); |
