static int minix_file_write(struct inode * inode, struct file * filp, const char * buf, int count) { off_t pos; int written,c; struct buffer_head * bh; char * p; if (!inode) { printk("minix_file_write: inode = NULL\n"); return -EINVAL; } if (!S_ISREG(inode->i_mode)) { printk("minix_file_write: mode = %07o\n",inode->i_mode); return -EINVAL; } if (filp->f_flags & O_APPEND) pos = inode->i_size; else pos = filp->f_pos; written = 0; while (written < count) { bh = minix_getblk(inode,pos/BLOCK_SIZE,1); if (!bh) { if (!written) written = -ENOSPC; break; } c = BLOCK_SIZE - (pos % BLOCK_SIZE); if (c > count-written) c = count-written; if (c != BLOCK_SIZE && !buffer_uptodate(bh)) { ll_rw_block(READ, 1, &bh); wait_on_buffer(bh); if (!buffer_uptodate(bh)) { brelse(bh); if (!written) written = -EIO; break; } } p = (pos % BLOCK_SIZE) + bh->b_data; memcpy_fromfs(p,buf,c); update_vm_cache(inode, pos, p, c); mark_buffer_uptodate(bh, 1); mark_buffer_dirty(bh, 0); brelse(bh); pos += c; written += c; buf += c; } if (pos > inode->i_size) inode->i_size = pos; inode->i_mtime = inode->i_ctime = CURRENT_TIME; filp->f_pos = pos; inode->i_dirt = 1; return written; }
struct buffer_head * minix_bread(struct inode * inode, int block, int create) { struct buffer_head * bh; bh = minix_getblk(inode,block,create); if (!bh || bh->b_uptodate) return bh; ll_rw_block(READ,bh); wait_on_buffer(bh); if (bh->b_uptodate) return bh; brelse(bh); return NULL; }