int sysv_add_link(struct dentry *dentry, struct inode *inode) { struct inode *dir = dentry->d_parent->d_inode; const char * name = dentry->d_name.name; int namelen = dentry->d_name.len; struct page *page = NULL; struct sysv_dir_entry * de; unsigned long npages = dir_pages(dir); unsigned long n; char *kaddr; loff_t pos; int err; /* We take care of directory expansion in the same loop */ for (n = 0; n <= npages; n++) { page = dir_get_page(dir, n); err = PTR_ERR(page); if (IS_ERR(page)) goto out; kaddr = (char*)page_address(page); de = (struct sysv_dir_entry *)kaddr; kaddr += PAGE_CACHE_SIZE - SYSV_DIRSIZE; while ((char *)de <= kaddr) { if (!de->inode) goto got_it; err = -EEXIST; if (namecompare(namelen, SYSV_NAMELEN, name, de->name)) goto out_page; de++; } dir_put_page(page); } BUG(); return -EINVAL; got_it: pos = page_offset(page) + (char*)de - (char*)page_address(page); lock_page(page); err = __sysv_write_begin(NULL, page->mapping, pos, SYSV_DIRSIZE, AOP_FLAG_UNINTERRUPTIBLE, &page, NULL); if (err) goto out_unlock; memcpy (de->name, name, namelen); memset (de->name + namelen, 0, SYSV_DIRSIZE - namelen - 2); de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino); err = dir_commit_chunk(page, pos, SYSV_DIRSIZE); dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC; mark_inode_dirty(dir); out_page: dir_put_page(page); out: return err; out_unlock: unlock_page(page); goto out_page; }
int sysv_add_link(struct dentry *dentry, struct inode *inode) { struct inode *dir = dentry->d_parent->d_inode; const char * name = dentry->d_name.name; int namelen = dentry->d_name.len; struct page *page = NULL; struct sysv_dir_entry * de; unsigned long npages = dir_pages(dir); unsigned long n; char *kaddr; unsigned from, to; int err; /* We take care of directory expansion in the same loop */ for (n = 0; n <= npages; n++) { page = dir_get_page(dir, n); err = PTR_ERR(page); if (IS_ERR(page)) goto out; kaddr = (char*)page_address(page); de = (struct sysv_dir_entry *)kaddr; kaddr += PAGE_CACHE_SIZE - SYSV_DIRSIZE; while ((char *)de <= kaddr) { if (!de->inode) goto got_it; err = -EEXIST; if (namecompare(namelen, SYSV_NAMELEN, name, de->name)) goto out_page; de++; } dir_put_page(page); } BUG(); return -EINVAL; got_it: from = (char*)de - (char*)page_address(page); to = from + SYSV_DIRSIZE; lock_page(page); err = page->mapping->a_ops->prepare_write(NULL, page, from, to); if (err) goto out_unlock; memcpy (de->name, name, namelen); memset (de->name + namelen, 0, SYSV_DIRSIZE - namelen - 2); de->inode = cpu_to_fs16(inode->i_sb, inode->i_ino); err = dir_commit_chunk(page, from, to); dir->i_mtime = dir->i_ctime = CURRENT_TIME; mark_inode_dirty(dir); out_unlock: UnlockPage(page); out_page: dir_put_page(page); out: return err; }
static int sysv_readdir(struct file * filp, void * dirent, filldir_t filldir) { unsigned long pos = filp->f_pos; struct inode *inode = filp->f_dentry->d_inode; struct super_block *sb = inode->i_sb; unsigned offset = pos & ~PAGE_CACHE_MASK; unsigned long n = pos >> PAGE_CACHE_SHIFT; unsigned long npages = dir_pages(inode); lock_kernel(); pos = (pos + SYSV_DIRSIZE-1) & ~(SYSV_DIRSIZE-1); if (pos >= inode->i_size) goto done; for ( ; n < npages; n++, offset = 0) { char *kaddr, *limit; struct sysv_dir_entry *de; struct page *page = dir_get_page(inode, n); if (IS_ERR(page)) continue; kaddr = (char *)page_address(page); de = (struct sysv_dir_entry *)(kaddr+offset); limit = kaddr + PAGE_CACHE_SIZE - SYSV_DIRSIZE; for ( ;(char*)de <= limit; de++) { char *name = de->name; int over; if (!de->inode) continue; offset = (char *)de - kaddr; over = filldir(dirent, name, strnlen(name,SYSV_NAMELEN), (n<<PAGE_CACHE_SHIFT) | offset, fs16_to_cpu(SYSV_SB(sb), de->inode), DT_UNKNOWN); if (over) { dir_put_page(page); goto done; } } dir_put_page(page); } done: filp->f_pos = (n << PAGE_CACHE_SHIFT) | offset; update_atime(inode); unlock_kernel(); return 0; }
/** * vxfs_find_entry - find a mathing directory entry for a dentry * @ip: directory inode * @dp: dentry for which we want to find a direct * @ppp: gets filled with the page the return value sits in * * Description: * vxfs_find_entry finds a &struct vxfs_direct for the VFS directory * cache entry @dp. @ppp will be filled with the page the return * value resides in. * * Returns: * The wanted direct on success, else a NULL pointer. */ static struct vxfs_direct * vxfs_find_entry(struct inode *ip, struct dentry *dp, struct page **ppp) { u_long npages, page, nblocks, pblocks, block; u_long bsize = ip->i_sb->s_blocksize; const char *name = dp->d_name.name; int namelen = dp->d_name.len; npages = dir_pages(ip); nblocks = dir_blocks(ip); pblocks = VXFS_BLOCK_PER_PAGE(ip->i_sb); for (page = 0; page < npages; page++) { caddr_t kaddr; struct page *pp; pp = vxfs_get_page(ip->i_mapping, page); if (IS_ERR(pp)) continue; kaddr = (caddr_t)page_address(pp); for (block = 0; block <= nblocks && block <= pblocks; block++) { caddr_t baddr, limit; struct vxfs_dirblk *dbp; struct vxfs_direct *de; baddr = kaddr + (block * bsize); limit = baddr + bsize - VXFS_DIRLEN(1); dbp = (struct vxfs_dirblk *)baddr; de = (struct vxfs_direct *)(baddr + VXFS_DIRBLKOV(dbp)); for (; (caddr_t)de <= limit; de = vxfs_next_entry(de)) { if (!de->d_reclen) break; if (!de->d_ino) continue; if (vxfs_match(namelen, name, de)) { *ppp = pp; return (de); } } } vxfs_put_page(pp); } return NULL; }
/* * sysv_find_entry() * * finds an entry in the specified directory with the wanted name. It * returns the cache buffer in which the entry was found, and the entry * itself (as a parameter - res_dir). It does NOT read the inode of the * entry - you'll have to do that yourself if you want to. */ struct sysv_dir_entry *sysv_find_entry(struct dentry *dentry, struct page **res_page) { const char * name = dentry->d_name.name; int namelen = dentry->d_name.len; struct inode * dir = dentry->d_parent->d_inode; unsigned long start, n; unsigned long npages = dir_pages(dir); struct page *page = NULL; struct sysv_dir_entry *de; *res_page = NULL; start = SYSV_I(dir)->i_dir_start_lookup; if (start >= npages) start = 0; n = start; do { char *kaddr; page = dir_get_page(dir, n); if (!IS_ERR(page)) { kaddr = (char*)page_address(page); de = (struct sysv_dir_entry *) kaddr; kaddr += PAGE_CACHE_SIZE - SYSV_DIRSIZE; for ( ; (char *) de <= kaddr ; de++) { if (!de->inode) continue; if (namecompare(namelen, SYSV_NAMELEN, name, de->name)) goto found; } dir_put_page(page); } if (++n >= npages) n = 0; } while (n != start); return NULL; found: SYSV_I(dir)->i_dir_start_lookup = n; *res_page = page; return de; }
static int sysv_readdir(struct file *file, struct dir_context *ctx) { unsigned long pos = ctx->pos; struct inode *inode = file_inode(file); struct super_block *sb = inode->i_sb; unsigned long npages = dir_pages(inode); unsigned offset; unsigned long n; ctx->pos = pos = (pos + SYSV_DIRSIZE-1) & ~(SYSV_DIRSIZE-1); if (pos >= inode->i_size) return 0; offset = pos & ~PAGE_MASK; n = pos >> PAGE_SHIFT; for ( ; n < npages; n++, offset = 0) { char *kaddr, *limit; struct sysv_dir_entry *de; struct page *page = dir_get_page(inode, n); if (IS_ERR(page)) continue; kaddr = (char *)page_address(page); de = (struct sysv_dir_entry *)(kaddr+offset); limit = kaddr + PAGE_SIZE - SYSV_DIRSIZE; for ( ;(char*)de <= limit; de++, ctx->pos += sizeof(*de)) { char *name = de->name; if (!de->inode) continue; if (!dir_emit(ctx, name, strnlen(name,SYSV_NAMELEN), fs16_to_cpu(SYSV_SB(sb), de->inode), DT_UNKNOWN)) { dir_put_page(page); return 0; } } dir_put_page(page); } return 0; }
/* * routine to check that the specified directory is empty (for rmdir) */ int sysv_empty_dir(struct inode * inode) { struct super_block *sb = inode->i_sb; struct page *page = NULL; unsigned long i, npages = dir_pages(inode); for (i = 0; i < npages; i++) { char *kaddr; struct sysv_dir_entry * de; page = dir_get_page(inode, i); if (IS_ERR(page)) continue; kaddr = (char *)page_address(page); de = (struct sysv_dir_entry *)kaddr; kaddr += PAGE_CACHE_SIZE-SYSV_DIRSIZE; for ( ;(char *)de <= kaddr; de++) { if (!de->inode) continue; /* check for . and .. */ if (de->name[0] != '.') goto not_empty; if (!de->name[1]) { if (de->inode == cpu_to_fs16(SYSV_SB(sb), inode->i_ino)) continue; goto not_empty; } if (de->name[1] != '.' || de->name[2]) goto not_empty; } dir_put_page(page); } return 1; not_empty: dir_put_page(page); return 0; }
/** * vxfs_readdir - read a directory * @fp: the directory to read * @retp: return buffer * @filler: filldir callback * * Description: * vxfs_readdir fills @retp with directory entries from @fp * using the VFS supplied callback @filler. * * Returns: * Zero. */ static int vxfs_readdir(struct file *fp, void *retp, filldir_t filler) { struct inode *ip = fp->f_path.dentry->d_inode; struct super_block *sbp = ip->i_sb; u_long bsize = sbp->s_blocksize; u_long page, npages, block, pblocks, nblocks, offset; loff_t pos; switch ((long)fp->f_pos) { case 0: if (filler(retp, ".", 1, fp->f_pos, ip->i_ino, DT_DIR) < 0) goto out; fp->f_pos++; /* fallthrough */ case 1: if (filler(retp, "..", 2, fp->f_pos, VXFS_INO(ip)->vii_dotdot, DT_DIR) < 0) goto out; fp->f_pos++; /* fallthrough */ } pos = fp->f_pos - 2; if (pos > VXFS_DIRROUND(ip->i_size)) return 0; npages = dir_pages(ip); nblocks = dir_blocks(ip); pblocks = VXFS_BLOCK_PER_PAGE(sbp); page = pos >> PAGE_CACHE_SHIFT; offset = pos & ~PAGE_CACHE_MASK; block = (u_long)(pos >> sbp->s_blocksize_bits) % pblocks; for (; page < npages; page++, block = 0) { caddr_t kaddr; struct page *pp; pp = vxfs_get_page(ip->i_mapping, page); if (IS_ERR(pp)) continue; kaddr = (caddr_t)page_address(pp); for (; block <= nblocks && block <= pblocks; block++) { caddr_t baddr, limit; struct vxfs_dirblk *dbp; struct vxfs_direct *de; baddr = kaddr + (block * bsize); limit = baddr + bsize - VXFS_DIRLEN(1); dbp = (struct vxfs_dirblk *)baddr; de = (struct vxfs_direct *) (offset ? (kaddr + offset) : (baddr + VXFS_DIRBLKOV(dbp))); for (; (caddr_t)de <= limit; de = vxfs_next_entry(de)) { int over; if (!de->d_reclen) break; if (!de->d_ino) continue; offset = (caddr_t)de - kaddr; over = filler(retp, de->d_name, de->d_namelen, ((page << PAGE_CACHE_SHIFT) | offset) + 2, de->d_ino, DT_UNKNOWN); if (over) { vxfs_put_page(pp); goto done; } } offset = 0; } vxfs_put_page(pp); offset = 0; } done: fp->f_pos = ((page << PAGE_CACHE_SHIFT) | offset) + 2; out: return 0; }
/** * vxfs_readdir - read a directory * @fp: the directory to read * @retp: return buffer * @filler: filldir callback * * Description: * vxfs_readdir fills @retp with directory entries from @fp * using the VFS supplied callback @filler. * * Returns: * Zero. */ static int vxfs_readdir(struct file *fp, struct dir_context *ctx) { struct inode *ip = file_inode(fp); struct super_block *sbp = ip->i_sb; u_long bsize = sbp->s_blocksize; u_long page, npages, block, pblocks, nblocks, offset; loff_t pos; if (ctx->pos == 0) { if (!dir_emit_dot(fp, ctx)) return 0; ctx->pos = 1; } if (ctx->pos == 1) { if (!dir_emit(ctx, "..", 2, VXFS_INO(ip)->vii_dotdot, DT_DIR)) return 0; ctx->pos = 2; } pos = ctx->pos - 2; if (pos > VXFS_DIRROUND(ip->i_size)) return 0; npages = dir_pages(ip); nblocks = dir_blocks(ip); pblocks = VXFS_BLOCK_PER_PAGE(sbp); page = pos >> PAGE_CACHE_SHIFT; offset = pos & ~PAGE_CACHE_MASK; block = (u_long)(pos >> sbp->s_blocksize_bits) % pblocks; for (; page < npages; page++, block = 0) { char *kaddr; struct page *pp; pp = vxfs_get_page(ip->i_mapping, page); if (IS_ERR(pp)) continue; kaddr = (char *)page_address(pp); for (; block <= nblocks && block <= pblocks; block++) { char *baddr, *limit; struct vxfs_dirblk *dbp; struct vxfs_direct *de; baddr = kaddr + (block * bsize); limit = baddr + bsize - VXFS_DIRLEN(1); dbp = (struct vxfs_dirblk *)baddr; de = (struct vxfs_direct *) (offset ? (kaddr + offset) : (baddr + VXFS_DIRBLKOV(dbp))); for (; (char *)de <= limit; de = vxfs_next_entry(de)) { if (!de->d_reclen) break; if (!de->d_ino) continue; offset = (char *)de - kaddr; ctx->pos = ((page << PAGE_CACHE_SHIFT) | offset) + 2; if (!dir_emit(ctx, de->d_name, de->d_namelen, de->d_ino, DT_UNKNOWN)) { vxfs_put_page(pp); return 0; } } offset = 0; } vxfs_put_page(pp); offset = 0; } ctx->pos = ((page << PAGE_CACHE_SHIFT) | offset) + 2; return 0; }