X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;ds=sidebyside;f=fs%2Forangefs%2Fdir.c;h=d327cbd17756dcbc18ca787602e436c24e70d198;hb=e942661130e7221d4aeac9804ff100e7516470f3;hp=284373a57a082fa0e38422afbc49fa2e8519b0df;hpb=8b2ada27dc1045e8191673bf769a1136ce8a0127;p=karo-tx-linux.git diff --git a/fs/orangefs/dir.c b/fs/orangefs/dir.c index 284373a57a08..d327cbd17756 100644 --- a/fs/orangefs/dir.c +++ b/fs/orangefs/dir.c @@ -1,396 +1,404 @@ /* - * (C) 2001 Clemson University and The University of Chicago - * - * See COPYING in top-level directory. + * Copyright 2017 Omnibond Systems, L.L.C. */ #include "protocol.h" #include "orangefs-kernel.h" #include "orangefs-bufmap.h" +struct orangefs_dir_part { + struct orangefs_dir_part *next; + size_t len; +}; + +struct orangefs_dir { + __u64 token; + struct orangefs_dir_part *part; + loff_t end; + int error; +}; + +#define PART_SHIFT (24) +#define PART_SIZE (1<<24) +#define PART_MASK (~(PART_SIZE - 1)) + /* - * decode routine used by kmod to deal with the blob sent from - * userspace for readdirs. The blob contains zero or more of these - * sub-blobs: - * __u32 - represents length of the character string that follows. - * string - between 1 and ORANGEFS_NAME_MAX bytes long. - * padding - (if needed) to cause the __u32 plus the string to be - * eight byte aligned. - * khandle - sizeof(khandle) bytes. + * There can be up to 512 directory entries. Each entry is encoded as + * follows: + * 4 bytes: string size (n) + * n bytes: string + * 1 byte: trailing zero + * padding to 8 bytes + * 16 bytes: khandle + * padding to 8 bytes + * + * The trailer_buf starts with a struct orangefs_readdir_response_s + * which must be skipped to get to the directory data. + * + * The data which is received from the userspace daemon is termed a + * part and is stored in a linked list in case more than one part is + * needed for a large directory. + * + * The position pointer (ctx->pos) encodes the part and offset on which + * to begin reading at. Bits above PART_SHIFT encode the part and bits + * below PART_SHIFT encode the offset. Parts are stored in a linked + * list which grows as data is received from the server. The overhead + * associated with managing the list is presumed to be small compared to + * the overhead of communicating with the server. + * + * As data is received from the server, it is placed at the end of the + * part list. Data is parsed from the current position as it is needed. + * When data is determined to be corrupt, it is either because the + * userspace component has sent back corrupt data or because the file + * pointer has been moved to an invalid location. Since the two cannot + * be differentiated, return EIO. + * + * Part zero is synthesized to contains `.' and `..'. Part one is the + * first part of the part list. */ -static long decode_dirents(char *ptr, size_t size, - struct orangefs_readdir_response_s *readdir) + +static int do_readdir(struct orangefs_inode_s *oi, + struct orangefs_dir *od, struct dentry *dentry, + struct orangefs_kernel_op_s *op) { - int i; - struct orangefs_readdir_response_s *rd = - (struct orangefs_readdir_response_s *) ptr; - char *buf = ptr; - int khandle_size = sizeof(struct orangefs_khandle); - size_t offset = offsetof(struct orangefs_readdir_response_s, - dirent_array); - /* 8 reflects eight byte alignment */ - int smallest_blob = khandle_size + 8; - __u32 len; - int aligned_len; - int sizeof_u32 = sizeof(__u32); - long ret; - - gossip_debug(GOSSIP_DIR_DEBUG, "%s: size:%zu:\n", __func__, size); - - /* size is = offset on empty dirs, > offset on non-empty dirs... */ - if (size < offset) { - gossip_err("%s: size:%zu: offset:%zu:\n", - __func__, - size, - offset); - ret = -EINVAL; - goto out; - } + struct orangefs_readdir_response_s *resp; + int bufi, r; - if ((size == offset) && (readdir->orangefs_dirent_outcount != 0)) { - gossip_err("%s: size:%zu: dirent_outcount:%d:\n", - __func__, - size, - readdir->orangefs_dirent_outcount); - ret = -EINVAL; - goto out; - } + /* + * Despite the badly named field, readdir does not use shared + * memory. However, there are a limited number of readdir + * slots, which must be allocated here. This flag simply tells + * the op scheduler to return the op here for retry. + */ + op->uses_shared_memory = 1; + op->upcall.req.readdir.refn = oi->refn; + op->upcall.req.readdir.token = od->token; + op->upcall.req.readdir.max_dirent_count = + ORANGEFS_MAX_DIRENT_COUNT_READDIR; - readdir->token = rd->token; - readdir->orangefs_dirent_outcount = rd->orangefs_dirent_outcount; - readdir->dirent_array = kcalloc(readdir->orangefs_dirent_outcount, - sizeof(*readdir->dirent_array), - GFP_KERNEL); - if (readdir->dirent_array == NULL) { - gossip_err("%s: kcalloc failed.\n", __func__); - ret = -ENOMEM; - goto out; +again: + bufi = orangefs_readdir_index_get(); + if (bufi < 0) { + od->error = bufi; + return bufi; } - buf += offset; - size -= offset; - - for (i = 0; i < readdir->orangefs_dirent_outcount; i++) { - if (size < smallest_blob) { - gossip_err("%s: size:%zu: smallest_blob:%d:\n", - __func__, - size, - smallest_blob); - ret = -EINVAL; - goto free; - } + op->upcall.req.readdir.buf_index = bufi; - len = *(__u32 *)buf; - if ((len < 1) || (len > ORANGEFS_NAME_MAX)) { - gossip_err("%s: len:%d:\n", __func__, len); - ret = -EINVAL; - goto free; - } + r = service_operation(op, "orangefs_readdir", + get_interruptible_flag(dentry->d_inode)); - gossip_debug(GOSSIP_DIR_DEBUG, - "%s: size:%zu: len:%d:\n", - __func__, - size, - len); + orangefs_readdir_index_put(bufi); - readdir->dirent_array[i].d_name = buf + sizeof_u32; - readdir->dirent_array[i].d_length = len; + if (op_state_purged(op)) { + if (r == -EAGAIN) { + vfree(op->downcall.trailer_buf); + goto again; + } else if (r == -EIO) { + vfree(op->downcall.trailer_buf); + od->error = r; + return r; + } + } - /* - * Calculate "aligned" length of this string and its - * associated __u32 descriptor. - */ - aligned_len = ((sizeof_u32 + len + 1) + 7) & ~7; - gossip_debug(GOSSIP_DIR_DEBUG, - "%s: aligned_len:%d:\n", - __func__, - aligned_len); + if (r < 0) { + vfree(op->downcall.trailer_buf); + od->error = r; + return r; + } else if (op->downcall.status) { + vfree(op->downcall.trailer_buf); + od->error = op->downcall.status; + return op->downcall.status; + } - /* - * The end of the blob should coincide with the end - * of the last sub-blob. - */ - if (size < aligned_len + khandle_size) { - gossip_err("%s: ran off the end of the blob.\n", - __func__); - ret = -EINVAL; - goto free; - } - size -= aligned_len + khandle_size; + /* + * The maximum size is size per entry times the 512 entries plus + * the header. This is well under the limit. + */ + if (op->downcall.trailer_size > PART_SIZE) { + vfree(op->downcall.trailer_buf); + od->error = -EIO; + return -EIO; + } - buf += aligned_len; + resp = (struct orangefs_readdir_response_s *) + op->downcall.trailer_buf; + od->token = resp->token; + return 0; +} - readdir->dirent_array[i].khandle = - *(struct orangefs_khandle *) buf; - buf += khandle_size; +static int parse_readdir(struct orangefs_dir *od, + struct orangefs_kernel_op_s *op) +{ + struct orangefs_dir_part *part, *new; + size_t count; + + count = 1; + part = od->part; + while (part) { + count++; + if (part->next) + part = part->next; + else + break; } - ret = buf - ptr; - gossip_debug(GOSSIP_DIR_DEBUG, "%s: returning:%ld:\n", __func__, ret); - goto out; -free: - kfree(readdir->dirent_array); - readdir->dirent_array = NULL; + new = (void *)op->downcall.trailer_buf; + new->next = NULL; + new->len = op->downcall.trailer_size - + sizeof(struct orangefs_readdir_response_s); + if (!od->part) + od->part = new; + else + part->next = new; + count++; + od->end = count << PART_SHIFT; -out: - return ret; + return 0; } -/* - * Read directory entries from an instance of an open directory. - */ -static int orangefs_readdir(struct file *file, struct dir_context *ctx) +static int orangefs_dir_more(struct orangefs_inode_s *oi, + struct orangefs_dir *od, struct dentry *dentry) { - int ret = 0; - int buffer_index; - /* - * ptoken supports Orangefs' distributed directory logic, added - * in 2.9.2. - */ - __u64 *ptoken = file->private_data; - __u64 pos = 0; - ino_t ino = 0; - struct dentry *dentry = file->f_path.dentry; - struct orangefs_kernel_op_s *new_op = NULL; - struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(dentry->d_inode); - struct orangefs_readdir_response_s readdir_response; - void *dents_buf; - int i = 0; - int len = 0; - ino_t current_ino = 0; - char *current_entry = NULL; - long bytes_decoded; - - gossip_debug(GOSSIP_DIR_DEBUG, - "%s: ctx->pos:%lld, ptoken = %llu\n", - __func__, - lld(ctx->pos), - llu(*ptoken)); - - pos = (__u64) ctx->pos; - - /* are we done? */ - if (pos == ORANGEFS_READDIR_END) { - gossip_debug(GOSSIP_DIR_DEBUG, - "Skipping to termination path\n"); - return 0; + struct orangefs_kernel_op_s *op; + int r; + + op = op_alloc(ORANGEFS_VFS_OP_READDIR); + if (!op) { + od->error = -ENOMEM; + return -ENOMEM; + } + r = do_readdir(oi, od, dentry, op); + if (r) { + od->error = r; + goto out; + } + r = parse_readdir(od, op); + if (r) { + od->error = r; + goto out; } - gossip_debug(GOSSIP_DIR_DEBUG, - "orangefs_readdir called on %pd (pos=%llu)\n", - dentry, llu(pos)); + od->error = 0; +out: + op_release(op); + return od->error; +} - memset(&readdir_response, 0, sizeof(readdir_response)); +static int fill_from_part(struct orangefs_dir_part *part, + struct dir_context *ctx) +{ + const int offset = sizeof(struct orangefs_readdir_response_s); + struct orangefs_khandle *khandle; + __u32 *len, padlen; + loff_t i; + char *s; + i = ctx->pos & ~PART_MASK; - new_op = op_alloc(ORANGEFS_VFS_OP_READDIR); - if (!new_op) - return -ENOMEM; + /* The file offset from userspace is too large. */ + if (i > part->len) + return 1; /* - * Only the indices are shared. No memory is actually shared, but the - * mechanism is used. + * If the seek pointer is positioned just before an entry it + * should find the next entry. */ - new_op->uses_shared_memory = 1; - new_op->upcall.req.readdir.refn = orangefs_inode->refn; - new_op->upcall.req.readdir.max_dirent_count = - ORANGEFS_MAX_DIRENT_COUNT_READDIR; - - gossip_debug(GOSSIP_DIR_DEBUG, - "%s: upcall.req.readdir.refn.khandle: %pU\n", - __func__, - &new_op->upcall.req.readdir.refn.khandle); + if (i % 8) + i = i + (8 - i%8)%8; - new_op->upcall.req.readdir.token = *ptoken; - -get_new_buffer_index: - buffer_index = orangefs_readdir_index_get(); - if (buffer_index < 0) { - ret = buffer_index; - gossip_lerr("orangefs_readdir: orangefs_readdir_index_get() failure (%d)\n", - ret); - goto out_free_op; + while (i < part->len) { + if (part->len < i + sizeof *len) + break; + len = (void *)part + offset + i; + /* + * len is the size of the string itself. padlen is the + * total size of the encoded string. + */ + padlen = (sizeof *len + *len + 1) + + (8 - (sizeof *len + *len + 1)%8)%8; + if (part->len < i + padlen + sizeof *khandle) + goto next; + s = (void *)part + offset + i + sizeof *len; + if (s[*len] != 0) + goto next; + khandle = (void *)part + offset + i + padlen; + if (!dir_emit(ctx, s, *len, + orangefs_khandle_to_ino(khandle), + DT_UNKNOWN)) + return 0; + i += padlen + sizeof *khandle; + i = i + (8 - i%8)%8; + BUG_ON(i > part->len); + ctx->pos = (ctx->pos & PART_MASK) | i; + continue; +next: + i += 8; } - new_op->upcall.req.readdir.buf_index = buffer_index; - - ret = service_operation(new_op, - "orangefs_readdir", - get_interruptible_flag(dentry->d_inode)); + return 1; +} - gossip_debug(GOSSIP_DIR_DEBUG, - "Readdir downcall status is %d. ret:%d\n", - new_op->downcall.status, - ret); +static int orangefs_dir_fill(struct orangefs_inode_s *oi, + struct orangefs_dir *od, struct dentry *dentry, + struct dir_context *ctx) +{ + struct orangefs_dir_part *part; + size_t count; - orangefs_readdir_index_put(buffer_index); + count = ((ctx->pos & PART_MASK) >> PART_SHIFT) - 1; - if (ret == -EAGAIN && op_state_purged(new_op)) { - /* Client-core indices are invalid after it restarted. */ - gossip_debug(GOSSIP_DIR_DEBUG, - "%s: Getting new buffer_index for retry of readdir..\n", - __func__); - goto get_new_buffer_index; + part = od->part; + while (part->next && count) { + count--; + part = part->next; } - - if (ret == -EIO && op_state_purged(new_op)) { - gossip_err("%s: Client is down. Aborting readdir call.\n", - __func__); - goto out_free_op; + /* This means the userspace file offset is invalid. */ + if (count) { + od->error = -EIO; + return -EIO; } - if (ret < 0 || new_op->downcall.status != 0) { - gossip_debug(GOSSIP_DIR_DEBUG, - "Readdir request failed. Status:%d\n", - new_op->downcall.status); - if (ret >= 0) - ret = new_op->downcall.status; - goto out_free_op; + while (part && part->len) { + int r; + r = fill_from_part(part, ctx); + if (r < 0) { + od->error = r; + return r; + } else if (r == 0) { + /* Userspace buffer is full. */ + break; + } else { + /* + * The part ran out of data. Move to the next + * part. */ + ctx->pos = (ctx->pos & PART_MASK) + + (1 << PART_SHIFT); + part = part->next; + } } + return 0; +} - dents_buf = new_op->downcall.trailer_buf; - if (dents_buf == NULL) { - gossip_err("Invalid NULL buffer in readdir response\n"); - ret = -ENOMEM; - goto out_free_op; +static loff_t orangefs_dir_llseek(struct file *file, loff_t offset, + int whence) +{ + struct orangefs_dir *od = file->private_data; + /* + * Delete the stored data so userspace sees new directory + * entries. + */ + if (!whence && offset < od->end) { + struct orangefs_dir_part *part = od->part; + while (part) { + struct orangefs_dir_part *next = part->next; + vfree(part); + part = next; + } + od->token = ORANGEFS_ITERATE_START; + od->part = NULL; + od->end = 1 << PART_SHIFT; } + return default_llseek(file, offset, whence); +} - bytes_decoded = decode_dirents(dents_buf, new_op->downcall.trailer_size, - &readdir_response); - if (bytes_decoded < 0) { - ret = bytes_decoded; - gossip_err("Could not decode readdir from buffer %d\n", ret); - goto out_vfree; - } +static int orangefs_dir_iterate(struct file *file, + struct dir_context *ctx) +{ + struct orangefs_inode_s *oi; + struct orangefs_dir *od; + struct dentry *dentry; + int r; - if (bytes_decoded != new_op->downcall.trailer_size) { - gossip_err("orangefs_readdir: # bytes decoded (%ld) " - "!= trailer size (%ld)\n", - bytes_decoded, - (long)new_op->downcall.trailer_size); - ret = -EINVAL; - goto out_destroy_handle; - } + dentry = file->f_path.dentry; + oi = ORANGEFS_I(dentry->d_inode); + od = file->private_data; - /* - * orangefs doesn't actually store dot and dot-dot, but - * we need to have them represented. - */ - if (pos == 0) { - ino = get_ino_from_khandle(dentry->d_inode); - gossip_debug(GOSSIP_DIR_DEBUG, - "%s: calling dir_emit of \".\" with pos = %llu\n", - __func__, - llu(pos)); - ret = dir_emit(ctx, ".", 1, ino, DT_DIR); - pos += 1; - } + if (od->error) + return od->error; - if (pos == 1) { - ino = get_parent_ino_from_dentry(dentry); - gossip_debug(GOSSIP_DIR_DEBUG, - "%s: calling dir_emit of \"..\" with pos = %llu\n", - __func__, - llu(pos)); - ret = dir_emit(ctx, "..", 2, ino, DT_DIR); - pos += 1; + if (ctx->pos == 0) { + if (!dir_emit_dot(file, ctx)) + return 0; + ctx->pos++; + } + if (ctx->pos == 1) { + if (!dir_emit_dotdot(file, ctx)) + return 0; + ctx->pos = 1 << PART_SHIFT; } /* - * we stored ORANGEFS_ITERATE_NEXT in ctx->pos last time around - * to prevent "finding" dot and dot-dot on any iteration - * other than the first. + * The seek position is in the first synthesized part but is not + * valid. */ - if (ctx->pos == ORANGEFS_ITERATE_NEXT) - ctx->pos = 0; - - gossip_debug(GOSSIP_DIR_DEBUG, - "%s: dirent_outcount:%d:\n", - __func__, - readdir_response.orangefs_dirent_outcount); - for (i = ctx->pos; - i < readdir_response.orangefs_dirent_outcount; - i++) { - len = readdir_response.dirent_array[i].d_length; - current_entry = readdir_response.dirent_array[i].d_name; - current_ino = orangefs_khandle_to_ino( - &readdir_response.dirent_array[i].khandle); - - gossip_debug(GOSSIP_DIR_DEBUG, - "calling dir_emit for %s with len %d" - ", ctx->pos %ld\n", - current_entry, - len, - (unsigned long)ctx->pos); - /* - * type is unknown. We don't return object type - * in the dirent_array. This leaves getdents - * clueless about type. - */ - ret = - dir_emit(ctx, current_entry, len, current_ino, DT_UNKNOWN); - if (!ret) - break; - ctx->pos++; - gossip_debug(GOSSIP_DIR_DEBUG, - "%s: ctx->pos:%lld\n", - __func__, - lld(ctx->pos)); + if ((ctx->pos & PART_MASK) == 0) + return -EIO; - } + r = 0; /* - * we ran all the way through the last batch, set up for - * getting another batch... + * Must read more if the user has sought past what has been read + * so far. Stop a user who has sought past the end. */ - if (ret) { - *ptoken = readdir_response.token; - ctx->pos = ORANGEFS_ITERATE_NEXT; + while (od->token != ORANGEFS_ITERATE_END && + ctx->pos > od->end) { + r = orangefs_dir_more(oi, od, dentry); + if (r) + return r; + } + if (od->token == ORANGEFS_ITERATE_END && ctx->pos > od->end) + return -EIO; + + /* Then try to fill if there's any left in the buffer. */ + if (ctx->pos < od->end) { + r = orangefs_dir_fill(oi, od, dentry, ctx); + if (r) + return r; } - /* - * Did we hit the end of the directory? - */ - if (readdir_response.token == ORANGEFS_READDIR_END) { - gossip_debug(GOSSIP_DIR_DEBUG, - "End of dir detected; setting ctx->pos to ORANGEFS_READDIR_END.\n"); - ctx->pos = ORANGEFS_READDIR_END; + /* Finally get some more and try to fill. */ + if (od->token != ORANGEFS_ITERATE_END) { + r = orangefs_dir_more(oi, od, dentry); + if (r) + return r; + r = orangefs_dir_fill(oi, od, dentry, ctx); } -out_destroy_handle: - /* kfree(NULL) is safe */ - kfree(readdir_response.dirent_array); -out_vfree: - gossip_debug(GOSSIP_DIR_DEBUG, "vfree %p\n", dents_buf); - vfree(dents_buf); -out_free_op: - op_release(new_op); - gossip_debug(GOSSIP_DIR_DEBUG, "orangefs_readdir returning %d\n", ret); - return ret; + return r; } static int orangefs_dir_open(struct inode *inode, struct file *file) { - __u64 *ptoken; - - file->private_data = kmalloc(sizeof(__u64), GFP_KERNEL); + struct orangefs_dir *od; + file->private_data = kmalloc(sizeof(struct orangefs_dir), + GFP_KERNEL); if (!file->private_data) return -ENOMEM; - - ptoken = file->private_data; - *ptoken = ORANGEFS_READDIR_START; + od = file->private_data; + od->token = ORANGEFS_ITERATE_START; + od->part = NULL; + od->end = 1 << PART_SHIFT; + od->error = 0; return 0; } static int orangefs_dir_release(struct inode *inode, struct file *file) { + struct orangefs_dir *od = file->private_data; + struct orangefs_dir_part *part = od->part; orangefs_flush_inode(inode); - kfree(file->private_data); + while (part) { + struct orangefs_dir_part *next = part->next; + vfree(part); + part = next; + } + kfree(od); return 0; } -/** ORANGEFS implementation of VFS directory operations */ const struct file_operations orangefs_dir_operations = { + .llseek = orangefs_dir_llseek, .read = generic_read_dir, - .iterate = orangefs_readdir, + .iterate = orangefs_dir_iterate, .open = orangefs_dir_open, - .release = orangefs_dir_release, + .release = orangefs_dir_release };