// SPDX-License-Identifier: GPL-2.0 /* * (C) 2001 Clemson University and The University of Chicago * Copyright 2018 Omnibond Systems, L.L.C. * * See COPYING in top-level directory. */ /* * Linux VFS file operations. */ #include "protocol.h" #include "orangefs-kernel.h" #include "orangefs-bufmap.h" #include <linux/fs.h> #include <linux/filelock.h> #include <linux/pagemap.h> static int flush_racache(struct inode *inode) { struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode); struct orangefs_kernel_op_s *new_op; int ret; gossip_debug(GOSSIP_UTILS_DEBUG, "%s: %pU: Handle is %pU | fs_id %d\n", __func__, get_khandle_from_ino(inode), &orangefs_inode->refn.khandle, orangefs_inode->refn.fs_id); new_op = op_alloc(ORANGEFS_VFS_OP_RA_FLUSH); if (!new_op) return -ENOMEM; new_op->upcall.req.ra_cache_flush.refn = orangefs_inode->refn; ret = service_operation(new_op, "orangefs_flush_racache", get_interruptible_flag(inode)); gossip_debug(GOSSIP_UTILS_DEBUG, "%s: got return value of %d\n", __func__, ret); op_release(new_op); return ret; } /* * Post and wait for the I/O upcall to finish */ ssize_t wait_for_direct_io(enum ORANGEFS_io_type type, struct inode *inode, loff_t *offset, struct iov_iter *iter, size_t total_size, loff_t readahead_size, struct orangefs_write_range *wr, int *index_return, struct file *file) { struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode); struct orangefs_khandle *handle = &orangefs_inode->refn.khandle; struct orangefs_kernel_op_s *new_op = NULL; int buffer_index; ssize_t ret; size_t copy_amount; int open_for_read; int open_for_write; new_op = op_alloc(ORANGEFS_VFS_OP_FILE_IO); if (!new_op) return -ENOMEM; /* synchronous I/O */ new_op->upcall.req.io.readahead_size = readahead_size; new_op->upcall.req.io.io_type = type; new_op->upcall.req.io.refn = orangefs_inode->refn; populate_shared_memory: /* get a shared buffer index */ buffer_index = orangefs_bufmap_get(); if (buffer_index < 0) { ret = buffer_index; gossip_debug(GOSSIP_FILE_DEBUG, "%s: orangefs_bufmap_get failure (%zd)\n", __func__, ret); goto out; } gossip_debug(GOSSIP_FILE_DEBUG, "%s(%pU): GET op %p -> buffer_index %d\n", __func__, handle, new_op, buffer_index); new_op->uses_shared_memory = 1; new_op->upcall.req.io.buf_index = buffer_index; new_op->upcall.req.io.count = total_size; new_op->upcall.req.io.offset = *offset; if (type == ORANGEFS_IO_WRITE && wr) { new_op->upcall.uid = from_kuid(&init_user_ns, wr->uid); new_op->upcall.gid = from_kgid(&init_user_ns, wr->gid); } /* * Orangefs has no open, and orangefs checks file permissions * on each file access. Posix requires that file permissions * be checked on open and nowhere else. Orangefs-through-the-kernel * needs to seem posix compliant. * * The VFS opens files, even if the filesystem provides no * method. We can see if a file was successfully opened for * read and or for write by looking at file->f_mode. * * When writes are flowing from the page cache, file is no * longer available. We can trust the VFS to have checked * file->f_mode before writing to the page cache. * * The mode of a file might change between when it is opened * and IO commences, or it might be created with an arbitrary mode. * * We'll make sure we don't hit EACCES during the IO stage by * using UID 0. Some of the time we have access without changing * to UID 0 - how to check? */ if (file) { open_for_write = file->f_mode & FMODE_WRITE; open_for_read = file->f_mode & FMODE_READ; } else { open_for_write = 1; open_for_read = 0; /* not relevant? */ } if ((type == ORANGEFS_IO_WRITE) && open_for_write) new_op->upcall.uid = 0; if ((type == ORANGEFS_IO_READ) && open_for_read) new_op->upcall.uid = 0; gossip_debug(GOSSIP_FILE_DEBUG, "%s(%pU): offset: %llu total_size: %zd\n", __func__, handle, llu(*offset), total_size); /* * Stage 1: copy the buffers into client-core's address space */ if (type == ORANGEFS_IO_WRITE && total_size) { ret = orangefs_bufmap_copy_from_iovec(iter, buffer_index, total_size); if (ret < 0) { gossip_err("%s: Failed to copy-in buffers. Please make sure that the pvfs2-client is running. %ld\n", __func__, (long)ret); goto out; } } gossip_debug(GOSSIP_FILE_DEBUG, "%s(%pU): Calling post_io_request with tag (%llu)\n", __func__, handle, llu(new_op->tag)); /* Stage 2: Service the I/O operation */ ret = service_operation(new_op, type == ORANGEFS_IO_WRITE ? "file_write" : "file_read", get_interruptible_flag(inode)); /* * If service_operation() returns -EAGAIN #and# the operation was * purged from orangefs_request_list or htable_ops_in_progress, then * we know that the client was restarted, causing the shared memory * area to be wiped clean. To restart a write operation in this * case, we must re-copy the data from the user's iovec to a NEW * shared memory location. To restart a read operation, we must get * a new shared memory location. */ if (ret == -EAGAIN && op_state_purged(new_op)) { orangefs_bufmap_put(buffer_index); if (type == ORANGEFS_IO_WRITE) iov_iter_revert(iter, total_size); gossip_debug(GOSSIP_FILE_DEBUG, "%s:going to repopulate_shared_memory.\n", __func__); goto populate_shared_memory; } if (ret < 0) { if (ret == -EINTR) { /* * We can't return EINTR if any data was written, * it's not POSIX. It is minimally acceptable * to give a partial write, the way NFS does. * * It would be optimal to return all or nothing, * but if a userspace write is bigger than * an IO buffer, and the interrupt occurs * between buffer writes, that would not be * possible. */ switch (new_op->op_state - OP_VFS_STATE_GIVEN_UP) { /* * If the op was waiting when the interrupt * occurred, then the client-core did not * trigger the write. */ case OP_VFS_STATE_WAITING: if (*offset == 0) ret = -EINTR; else ret = 0; break; /* * If the op was in progress when the interrupt * occurred, then the client-core was able to * trigger the write. */ case OP_VFS_STATE_INPROGR: if (type == ORANGEFS_IO_READ) ret = -EINTR; else ret = total_size; break; default: gossip_err("%s: unexpected op state :%d:.\n", __func__, new_op->op_state); ret = 0; break; } gossip_debug(GOSSIP_FILE_DEBUG, "%s: got EINTR, state:%d: %p\n", __func__, new_op->op_state, new_op); } else { gossip_err("%s: error in %s handle %pU, returning %zd\n", __func__, type == ORANGEFS_IO_READ ? "read from" : "write to", handle, ret); } if (orangefs_cancel_op_in_progress(new_op)) return ret; goto out; } /* * Stage 3: Post copy buffers from client-core's address space */ if (type == ORANGEFS_IO_READ && new_op->downcall.resp.io.amt_complete) { /* * NOTE: the iovector can either contain addresses which * can futher be kernel-space or user-space addresses. * or it can pointers to struct page's */ copy_amount = new_op->downcall.resp.io.amt_complete; ret = orangefs_bufmap_copy_to_iovec(iter, buffer_index, copy_amount); if (ret < 0) { gossip_err("%s: Failed to copy-out buffers. Please make sure that the pvfs2-client is running (%ld)\n", __func__, (long)ret); goto out; } } gossip_debug(GOSSIP_FILE_DEBUG, "%s(%pU): Amount %s, returned by the sys-io call:%d\n", __func__, handle, type == ORANGEFS_IO_READ ? "read" : "written", (int)new_op->downcall.resp.io.amt_complete); ret = new_op->downcall.resp.io.amt_complete; out: if (buffer_index >= 0) { orangefs_bufmap_put(buffer_index); gossip_debug(GOSSIP_FILE_DEBUG, "%s(%pU): PUT buffer_index %d\n", __func__, handle, buffer_index); } op_release(new_op); return ret; } int orangefs_revalidate_mapping(struct inode *inode) { struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(inode); struct address_space *mapping = inode->i_mapping; unsigned long *bitlock = &orangefs_inode->bitlock; int ret; while (1) { ret = wait_on_bit(bitlock, 1, TASK_KILLABLE); if (ret) return ret; spin_lock(&inode->i_lock); if (test_bit(1, bitlock)) { spin_unlock(&inode->i_lock); continue; } if (!time_before(jiffies, orangefs_inode->mapping_time)) break; spin_unlock(&inode->i_lock); return 0; } set_bit(1, bitlock); smp_wmb(); spin_unlock(&inode->i_lock); unmap_mapping_range(mapping, 0, 0, 0); ret = filemap_write_and_wait(mapping); if (!ret) ret = invalidate_inode_pages2(mapping); orangefs_inode->mapping_time = jiffies + orangefs_cache_timeout_msecs*HZ/1000; clear_bit(1, bitlock); smp_mb__after_atomic(); wake_up_bit(bitlock, 1); return ret; } static ssize_t orangefs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter) { int ret; orangefs_stats.reads++; down_read(&file_inode(iocb->ki_filp)->i_rwsem); ret = orangefs_revalidate_mapping(file_inode(iocb->ki_filp)); if (ret) goto out; ret = generic_file_read_iter(iocb, iter); out: up_read(&file_inode(iocb->ki_filp)->i_rwsem); return ret; } static ssize_t orangefs_file_splice_read(struct file *in, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags) { struct inode *inode = file_inode(in); ssize_t ret; orangefs_stats.reads++; down_read(&inode->i_rwsem); ret = orangefs_revalidate_mapping(inode); if (ret) goto out; ret = filemap_splice_read(in, ppos, pipe, len, flags); out: up_read(&inode->i_rwsem); return ret; } static ssize_t orangefs_file_write_iter(struct kiocb *iocb, struct iov_iter *iter) { int ret; orangefs_stats.writes++; if (iocb->ki_pos > i_size_read(file_inode(iocb->ki_filp))) { ret = orangefs_revalidate_mapping(file_inode(iocb->ki_filp)); if (ret) return ret; } ret = generic_file_write_iter(iocb, iter); return ret; } static vm_fault_t orangefs_fault(struct vm_fault *vmf) { struct file *file = vmf->vma->vm_file; int ret; ret = orangefs_inode_getattr(file->f_mapping->host, ORANGEFS_GETATTR_SIZE); if (ret == -ESTALE) ret = -EIO; if (ret) { gossip_err("%s: orangefs_inode_getattr failed, " "ret:%d:.\n", __func__, ret); return VM_FAULT_SIGBUS; } return filemap_fault(vmf); } static const struct vm_operations_struct orangefs_file_vm_ops = { .fault = orangefs_fault, .map_pages = filemap_map_pages, .page_mkwrite = orangefs_page_mkwrite, }; /* * Memory map a region of a file. */ static int orangefs_file_mmap(struct file *file, struct vm_area_struct *vma) { int ret; ret = orangefs_revalidate_mapping(file_inode(file)); if (ret) return ret; gossip_debug(GOSSIP_FILE_DEBUG, "orangefs_file_mmap: called on %pD\n", file); /* set the sequential readahead hint */ vm_flags_mod(vma, VM_SEQ_READ, VM_RAND_READ); file_accessed(file); vma->vm_ops = &orangefs_file_vm_ops; return 0; } #define mapping_nrpages(idata) ((idata)->nrpages) /* * Called to notify the module that there are no more references to * this file (i.e. no processes have it open). * * \note Not called when each file is closed. */ static int orangefs_file_release(struct inode *inode, struct file *file) { gossip_debug(GOSSIP_FILE_DEBUG, "orangefs_file_release: called on %pD\n", file); /* * remove all associated inode pages from the page cache and * readahead cache (if any); this forces an expensive refresh of * data for the next caller of mmap (or 'get_block' accesses) */ if (mapping_nrpages(file->f_mapping)) { if (orangefs_features & ORANGEFS_FEATURE_READAHEAD) { gossip_debug(GOSSIP_INODE_DEBUG, "calling flush_racache on %pU\n", get_khandle_from_ino(inode)); flush_racache(inode); gossip_debug(GOSSIP_INODE_DEBUG, "flush_racache finished\n"); } } return 0; } /* * Push all data for a specific file onto permanent storage. */ static int orangefs_fsync(struct file *file, loff_t start, loff_t end, int datasync) { int ret; struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(file_inode(file)); struct orangefs_kernel_op_s *new_op = NULL; ret = filemap_write_and_wait_range(file_inode(file)->i_mapping, start, end); if (ret < 0) return ret; new_op = op_alloc(ORANGEFS_VFS_OP_FSYNC); if (!new_op) return -ENOMEM; new_op->upcall.req.fsync.refn = orangefs_inode->refn; ret = service_operation(new_op, "orangefs_fsync", get_interruptible_flag(file_inode(file))); gossip_debug(GOSSIP_FILE_DEBUG, "orangefs_fsync got return value of %d\n", ret); op_release(new_op); return ret; } /* * Change the file pointer position for an instance of an open file. * * \note If .llseek is overriden, we must acquire lock as described in * Documentation/filesystems/locking.rst. * * Future upgrade could support SEEK_DATA and SEEK_HOLE but would * require much changes to the FS */ static loff_t orangefs_file_llseek(struct file *file, loff_t offset, int origin) { int ret = -EINVAL; struct inode *inode = file_inode(file); if (origin == SEEK_END) { /* * revalidate the inode's file size. * NOTE: We are only interested in file size here, * so we set mask accordingly. */ ret = orangefs_inode_getattr(file->f_mapping->host, ORANGEFS_GETATTR_SIZE); if (ret == -ESTALE) ret = -EIO; if (ret) { gossip_debug(GOSSIP_FILE_DEBUG, "%s:%s:%d calling make bad inode\n", __FILE__, __func__, __LINE__); return ret; } } gossip_debug(GOSSIP_FILE_DEBUG, "orangefs_file_llseek: offset is %ld | origin is %d" " | inode size is %lu\n", (long)offset, origin, (unsigned long)i_size_read(inode)); return generic_file_llseek(file, offset, origin); } /* * Support local locks (locks that only this kernel knows about) * if Orangefs was mounted -o local_lock. */ static int orangefs_lock(struct file *filp, int cmd, struct file_lock *fl) { int rc = -EINVAL; if (ORANGEFS_SB(file_inode(filp)->i_sb)->flags & ORANGEFS_OPT_LOCAL_LOCK) { if (cmd == F_GETLK) { rc = 0; posix_test_lock(filp, fl); } else { rc = posix_lock_file(filp, fl, NULL); } } return rc; } static int orangefs_flush(struct file *file, fl_owner_t id) { /* * This is vfs_fsync_range(file, 0, LLONG_MAX, 0) without the * service_operation in orangefs_fsync. * * Do not send fsync to OrangeFS server on a close. Do send fsync * on an explicit fsync call. This duplicates historical OrangeFS * behavior. */ int r; r = filemap_write_and_wait_range(file->f_mapping, 0, LLONG_MAX); if (r > 0) return 0; else return r; } /** ORANGEFS implementation of VFS file operations */ const struct file_operations orangefs_file_operations = { .llseek = orangefs_file_llseek, .read_iter = orangefs_file_read_iter, .write_iter = orangefs_file_write_iter, .lock = orangefs_lock, .mmap = orangefs_file_mmap, .open = generic_file_open, .splice_read = orangefs_file_splice_read, .splice_write = iter_file_splice_write, .flush = orangefs_flush, .release = orangefs_file_release, .fsync = orangefs_fsync, };