/* * linux/fs/hpfs/buffer.c * * Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999 * * general buffer i/o */ #include <linux/sched.h> #include "hpfs_fn.h" void hpfs_lock_creation(struct super_block *s) { #ifdef DEBUG_LOCKS printk("lock creation\n"); #endif down(&hpfs_sb(s)->hpfs_creation_de); } void hpfs_unlock_creation(struct super_block *s) { #ifdef DEBUG_LOCKS printk("unlock creation\n"); #endif up(&hpfs_sb(s)->hpfs_creation_de); } /* Map a sector into a buffer and return pointers to it and to the buffer. */ void *hpfs_map_sector(struct super_block *s, unsigned secno, struct buffer_head **bhp, int ahead) { struct buffer_head *bh; cond_resched(); *bhp = bh = sb_bread(s, secno); if (bh != NULL) return bh->b_data; else { printk("HPFS: hpfs_map_sector: read error\n"); return NULL; } } /* Like hpfs_map_sector but don't read anything */ void *hpfs_get_sector(struct super_block *s, unsigned secno, struct buffer_head **bhp) { struct buffer_head *bh; /*return hpfs_map_sector(s, secno, bhp, 0);*/ cond_resched(); if ((*bhp = bh = sb_getblk(s, secno)) != NULL) { if (!buffer_uptodate(bh)) wait_on_buffer(bh); set_buffer_uptodate(bh); return bh->b_data; } else { printk("HPFS: hpfs_get_sector: getblk failed\n"); return NULL; } } /* Map 4 sectors into a 4buffer and return pointers to it and to the buffer. */ void *hpfs_map_4sectors(struct super_block *s, unsigned secno, struct quad_buffer_head *qbh, int ahead) { struct buffer_head *bh; char *data; cond_resched(); if (secno & 3) { printk("HPFS: hpfs_map_4sectors: unaligned read\n"); return NULL; } qbh->data = data = kmalloc(2048, GFP_NOFS); if (!data) { printk("HPFS: hpfs_map_4sectors: out of memory\n"); goto bail; } 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); return data; bail3: brelse(qbh->bh[2]); bail2: brelse(qbh->bh[1]); bail1: brelse(qbh->bh[0]); bail0: kfree(data); printk("HPFS: hpfs_map_4sectors: read error\n"); bail: return NULL; } /* Don't read sectors */ void *hpfs_get_4sectors(struct super_block *s, unsigned secno, struct quad_buffer_head *qbh) { cond_resched(); if (secno & 3) { printk("HPFS: hpfs_get_4sectors: unaligned read\n"); return NULL; } /*return hpfs_map_4sectors(s, secno, qbh, 0);*/ if (!(qbh->data = kmalloc(2048, GFP_NOFS))) { printk("HPFS: hpfs_get_4sectors: out of memory\n"); return NULL; } 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: return NULL; } void hpfs_brelse4(struct quad_buffer_head *qbh) { brelse(qbh->bh[3]); brelse(qbh->bh[2]); brelse(qbh->bh[1]); brelse(qbh->bh[0]); kfree(qbh->data); } void hpfs_mark_4buffers_dirty(struct quad_buffer_head *qbh) { PRINTK(("hpfs_mark_4buffers_dirty\n")); 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); mark_buffer_dirty(qbh->bh[0]); mark_buffer_dirty(qbh->bh[1]); mark_buffer_dirty(qbh->bh[2]); mark_buffer_dirty(qbh->bh[3]); }