From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- fs/afs/file.c | 598 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 598 insertions(+) create mode 100644 fs/afs/file.c (limited to 'fs/afs/file.c') diff --git a/fs/afs/file.c b/fs/afs/file.c new file mode 100644 index 000000000..2eeab57df --- /dev/null +++ b/fs/afs/file.c @@ -0,0 +1,598 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* AFS filesystem file handling + * + * Copyright (C) 2002, 2007 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "internal.h" + +static int afs_file_mmap(struct file *file, struct vm_area_struct *vma); +static int afs_symlink_read_folio(struct file *file, struct folio *folio); +static void afs_invalidate_folio(struct folio *folio, size_t offset, + size_t length); +static bool afs_release_folio(struct folio *folio, gfp_t gfp_flags); + +static ssize_t afs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter); +static void afs_vm_open(struct vm_area_struct *area); +static void afs_vm_close(struct vm_area_struct *area); +static vm_fault_t afs_vm_map_pages(struct vm_fault *vmf, pgoff_t start_pgoff, pgoff_t end_pgoff); + +const struct file_operations afs_file_operations = { + .open = afs_open, + .release = afs_release, + .llseek = generic_file_llseek, + .read_iter = afs_file_read_iter, + .write_iter = afs_file_write, + .mmap = afs_file_mmap, + .splice_read = generic_file_splice_read, + .splice_write = iter_file_splice_write, + .fsync = afs_fsync, + .lock = afs_lock, + .flock = afs_flock, +}; + +const struct inode_operations afs_file_inode_operations = { + .getattr = afs_getattr, + .setattr = afs_setattr, + .permission = afs_permission, +}; + +const struct address_space_operations afs_file_aops = { + .read_folio = netfs_read_folio, + .readahead = netfs_readahead, + .dirty_folio = afs_dirty_folio, + .launder_folio = afs_launder_folio, + .release_folio = afs_release_folio, + .invalidate_folio = afs_invalidate_folio, + .write_begin = afs_write_begin, + .write_end = afs_write_end, + .writepage = afs_writepage, + .writepages = afs_writepages, +}; + +const struct address_space_operations afs_symlink_aops = { + .read_folio = afs_symlink_read_folio, + .release_folio = afs_release_folio, + .invalidate_folio = afs_invalidate_folio, +}; + +static const struct vm_operations_struct afs_vm_ops = { + .open = afs_vm_open, + .close = afs_vm_close, + .fault = filemap_fault, + .map_pages = afs_vm_map_pages, + .page_mkwrite = afs_page_mkwrite, +}; + +/* + * Discard a pin on a writeback key. + */ +void afs_put_wb_key(struct afs_wb_key *wbk) +{ + if (wbk && refcount_dec_and_test(&wbk->usage)) { + key_put(wbk->key); + kfree(wbk); + } +} + +/* + * Cache key for writeback. + */ +int afs_cache_wb_key(struct afs_vnode *vnode, struct afs_file *af) +{ + struct afs_wb_key *wbk, *p; + + wbk = kzalloc(sizeof(struct afs_wb_key), GFP_KERNEL); + if (!wbk) + return -ENOMEM; + refcount_set(&wbk->usage, 2); + wbk->key = af->key; + + spin_lock(&vnode->wb_lock); + list_for_each_entry(p, &vnode->wb_keys, vnode_link) { + if (p->key == wbk->key) + goto found; + } + + key_get(wbk->key); + list_add_tail(&wbk->vnode_link, &vnode->wb_keys); + spin_unlock(&vnode->wb_lock); + af->wb = wbk; + return 0; + +found: + refcount_inc(&p->usage); + spin_unlock(&vnode->wb_lock); + af->wb = p; + kfree(wbk); + return 0; +} + +/* + * open an AFS file or directory and attach a key to it + */ +int afs_open(struct inode *inode, struct file *file) +{ + struct afs_vnode *vnode = AFS_FS_I(inode); + struct afs_file *af; + struct key *key; + int ret; + + _enter("{%llx:%llu},", vnode->fid.vid, vnode->fid.vnode); + + key = afs_request_key(vnode->volume->cell); + if (IS_ERR(key)) { + ret = PTR_ERR(key); + goto error; + } + + af = kzalloc(sizeof(*af), GFP_KERNEL); + if (!af) { + ret = -ENOMEM; + goto error_key; + } + af->key = key; + + ret = afs_validate(vnode, key); + if (ret < 0) + goto error_af; + + if (file->f_mode & FMODE_WRITE) { + ret = afs_cache_wb_key(vnode, af); + if (ret < 0) + goto error_af; + } + + if (file->f_flags & O_TRUNC) + set_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags); + + fscache_use_cookie(afs_vnode_cache(vnode), file->f_mode & FMODE_WRITE); + + file->private_data = af; + _leave(" = 0"); + return 0; + +error_af: + kfree(af); +error_key: + key_put(key); +error: + _leave(" = %d", ret); + return ret; +} + +/* + * release an AFS file or directory and discard its key + */ +int afs_release(struct inode *inode, struct file *file) +{ + struct afs_vnode_cache_aux aux; + struct afs_vnode *vnode = AFS_FS_I(inode); + struct afs_file *af = file->private_data; + loff_t i_size; + int ret = 0; + + _enter("{%llx:%llu},", vnode->fid.vid, vnode->fid.vnode); + + if ((file->f_mode & FMODE_WRITE)) + ret = vfs_fsync(file, 0); + + file->private_data = NULL; + if (af->wb) + afs_put_wb_key(af->wb); + + if ((file->f_mode & FMODE_WRITE)) { + i_size = i_size_read(&vnode->netfs.inode); + afs_set_cache_aux(vnode, &aux); + fscache_unuse_cookie(afs_vnode_cache(vnode), &aux, &i_size); + } else { + fscache_unuse_cookie(afs_vnode_cache(vnode), NULL, NULL); + } + + key_put(af->key); + kfree(af); + afs_prune_wb_keys(vnode); + _leave(" = %d", ret); + return ret; +} + +/* + * Allocate a new read record. + */ +struct afs_read *afs_alloc_read(gfp_t gfp) +{ + struct afs_read *req; + + req = kzalloc(sizeof(struct afs_read), gfp); + if (req) + refcount_set(&req->usage, 1); + + return req; +} + +/* + * Dispose of a ref to a read record. + */ +void afs_put_read(struct afs_read *req) +{ + if (refcount_dec_and_test(&req->usage)) { + if (req->cleanup) + req->cleanup(req); + key_put(req->key); + kfree(req); + } +} + +static void afs_fetch_data_notify(struct afs_operation *op) +{ + struct afs_read *req = op->fetch.req; + struct netfs_io_subrequest *subreq = req->subreq; + int error = op->error; + + if (error == -ECONNABORTED) + error = afs_abort_to_error(op->ac.abort_code); + req->error = error; + + if (subreq) { + __set_bit(NETFS_SREQ_CLEAR_TAIL, &subreq->flags); + netfs_subreq_terminated(subreq, error ?: req->actual_len, false); + req->subreq = NULL; + } else if (req->done) { + req->done(req); + } +} + +static void afs_fetch_data_success(struct afs_operation *op) +{ + struct afs_vnode *vnode = op->file[0].vnode; + + _enter("op=%08x", op->debug_id); + afs_vnode_commit_status(op, &op->file[0]); + afs_stat_v(vnode, n_fetches); + atomic_long_add(op->fetch.req->actual_len, &op->net->n_fetch_bytes); + afs_fetch_data_notify(op); +} + +static void afs_fetch_data_put(struct afs_operation *op) +{ + op->fetch.req->error = op->error; + afs_put_read(op->fetch.req); +} + +static const struct afs_operation_ops afs_fetch_data_operation = { + .issue_afs_rpc = afs_fs_fetch_data, + .issue_yfs_rpc = yfs_fs_fetch_data, + .success = afs_fetch_data_success, + .aborted = afs_check_for_remote_deletion, + .failed = afs_fetch_data_notify, + .put = afs_fetch_data_put, +}; + +/* + * Fetch file data from the volume. + */ +int afs_fetch_data(struct afs_vnode *vnode, struct afs_read *req) +{ + struct afs_operation *op; + + _enter("%s{%llx:%llu.%u},%x,,,", + vnode->volume->name, + vnode->fid.vid, + vnode->fid.vnode, + vnode->fid.unique, + key_serial(req->key)); + + op = afs_alloc_operation(req->key, vnode->volume); + if (IS_ERR(op)) { + if (req->subreq) + netfs_subreq_terminated(req->subreq, PTR_ERR(op), false); + return PTR_ERR(op); + } + + afs_op_set_vnode(op, 0, vnode); + + op->fetch.req = afs_get_read(req); + op->ops = &afs_fetch_data_operation; + return afs_do_sync_operation(op); +} + +static void afs_issue_read(struct netfs_io_subrequest *subreq) +{ + struct afs_vnode *vnode = AFS_FS_I(subreq->rreq->inode); + struct afs_read *fsreq; + + fsreq = afs_alloc_read(GFP_NOFS); + if (!fsreq) + return netfs_subreq_terminated(subreq, -ENOMEM, false); + + fsreq->subreq = subreq; + fsreq->pos = subreq->start + subreq->transferred; + fsreq->len = subreq->len - subreq->transferred; + fsreq->key = key_get(subreq->rreq->netfs_priv); + fsreq->vnode = vnode; + fsreq->iter = &fsreq->def_iter; + + iov_iter_xarray(&fsreq->def_iter, ITER_DEST, + &fsreq->vnode->netfs.inode.i_mapping->i_pages, + fsreq->pos, fsreq->len); + + afs_fetch_data(fsreq->vnode, fsreq); + afs_put_read(fsreq); +} + +static int afs_symlink_read_folio(struct file *file, struct folio *folio) +{ + struct afs_vnode *vnode = AFS_FS_I(folio->mapping->host); + struct afs_read *fsreq; + int ret; + + fsreq = afs_alloc_read(GFP_NOFS); + if (!fsreq) + return -ENOMEM; + + fsreq->pos = folio_pos(folio); + fsreq->len = folio_size(folio); + fsreq->vnode = vnode; + fsreq->iter = &fsreq->def_iter; + iov_iter_xarray(&fsreq->def_iter, ITER_DEST, &folio->mapping->i_pages, + fsreq->pos, fsreq->len); + + ret = afs_fetch_data(fsreq->vnode, fsreq); + if (ret == 0) + folio_mark_uptodate(folio); + folio_unlock(folio); + return ret; +} + +static int afs_init_request(struct netfs_io_request *rreq, struct file *file) +{ + rreq->netfs_priv = key_get(afs_file_key(file)); + return 0; +} + +static int afs_begin_cache_operation(struct netfs_io_request *rreq) +{ +#ifdef CONFIG_AFS_FSCACHE + struct afs_vnode *vnode = AFS_FS_I(rreq->inode); + + return fscache_begin_read_operation(&rreq->cache_resources, + afs_vnode_cache(vnode)); +#else + return -ENOBUFS; +#endif +} + +static int afs_check_write_begin(struct file *file, loff_t pos, unsigned len, + struct folio **foliop, void **_fsdata) +{ + struct afs_vnode *vnode = AFS_FS_I(file_inode(file)); + + return test_bit(AFS_VNODE_DELETED, &vnode->flags) ? -ESTALE : 0; +} + +static void afs_free_request(struct netfs_io_request *rreq) +{ + key_put(rreq->netfs_priv); +} + +const struct netfs_request_ops afs_req_ops = { + .init_request = afs_init_request, + .free_request = afs_free_request, + .begin_cache_operation = afs_begin_cache_operation, + .check_write_begin = afs_check_write_begin, + .issue_read = afs_issue_read, +}; + +int afs_write_inode(struct inode *inode, struct writeback_control *wbc) +{ + fscache_unpin_writeback(wbc, afs_vnode_cache(AFS_FS_I(inode))); + return 0; +} + +/* + * Adjust the dirty region of the page on truncation or full invalidation, + * getting rid of the markers altogether if the region is entirely invalidated. + */ +static void afs_invalidate_dirty(struct folio *folio, size_t offset, + size_t length) +{ + struct afs_vnode *vnode = AFS_FS_I(folio_inode(folio)); + unsigned long priv; + unsigned int f, t, end = offset + length; + + priv = (unsigned long)folio_get_private(folio); + + /* we clean up only if the entire page is being invalidated */ + if (offset == 0 && length == folio_size(folio)) + goto full_invalidate; + + /* If the page was dirtied by page_mkwrite(), the PTE stays writable + * and we don't get another notification to tell us to expand it + * again. + */ + if (afs_is_folio_dirty_mmapped(priv)) + return; + + /* We may need to shorten the dirty region */ + f = afs_folio_dirty_from(folio, priv); + t = afs_folio_dirty_to(folio, priv); + + if (t <= offset || f >= end) + return; /* Doesn't overlap */ + + if (f < offset && t > end) + return; /* Splits the dirty region - just absorb it */ + + if (f >= offset && t <= end) + goto undirty; + + if (f < offset) + t = offset; + else + f = end; + if (f == t) + goto undirty; + + priv = afs_folio_dirty(folio, f, t); + folio_change_private(folio, (void *)priv); + trace_afs_folio_dirty(vnode, tracepoint_string("trunc"), folio); + return; + +undirty: + trace_afs_folio_dirty(vnode, tracepoint_string("undirty"), folio); + folio_clear_dirty_for_io(folio); +full_invalidate: + trace_afs_folio_dirty(vnode, tracepoint_string("inval"), folio); + folio_detach_private(folio); +} + +/* + * invalidate part or all of a page + * - release a page and clean up its private data if offset is 0 (indicating + * the entire page) + */ +static void afs_invalidate_folio(struct folio *folio, size_t offset, + size_t length) +{ + _enter("{%lu},%zu,%zu", folio->index, offset, length); + + BUG_ON(!folio_test_locked(folio)); + + if (folio_get_private(folio)) + afs_invalidate_dirty(folio, offset, length); + + folio_wait_fscache(folio); + _leave(""); +} + +/* + * release a page and clean up its private state if it's not busy + * - return true if the page can now be released, false if not + */ +static bool afs_release_folio(struct folio *folio, gfp_t gfp) +{ + struct afs_vnode *vnode = AFS_FS_I(folio_inode(folio)); + + _enter("{{%llx:%llu}[%lu],%lx},%x", + vnode->fid.vid, vnode->fid.vnode, folio_index(folio), folio->flags, + gfp); + + /* deny if folio is being written to the cache and the caller hasn't + * elected to wait */ +#ifdef CONFIG_AFS_FSCACHE + if (folio_test_fscache(folio)) { + if (current_is_kswapd() || !(gfp & __GFP_FS)) + return false; + folio_wait_fscache(folio); + } + fscache_note_page_release(afs_vnode_cache(vnode)); +#endif + + if (folio_test_private(folio)) { + trace_afs_folio_dirty(vnode, tracepoint_string("rel"), folio); + folio_detach_private(folio); + } + + /* Indicate that the folio can be released */ + _leave(" = T"); + return true; +} + +static void afs_add_open_mmap(struct afs_vnode *vnode) +{ + if (atomic_inc_return(&vnode->cb_nr_mmap) == 1) { + down_write(&vnode->volume->cell->fs_open_mmaps_lock); + + if (list_empty(&vnode->cb_mmap_link)) + list_add_tail(&vnode->cb_mmap_link, + &vnode->volume->cell->fs_open_mmaps); + + up_write(&vnode->volume->cell->fs_open_mmaps_lock); + } +} + +static void afs_drop_open_mmap(struct afs_vnode *vnode) +{ + if (!atomic_dec_and_test(&vnode->cb_nr_mmap)) + return; + + down_write(&vnode->volume->cell->fs_open_mmaps_lock); + + if (atomic_read(&vnode->cb_nr_mmap) == 0) + list_del_init(&vnode->cb_mmap_link); + + up_write(&vnode->volume->cell->fs_open_mmaps_lock); + flush_work(&vnode->cb_work); +} + +/* + * Handle setting up a memory mapping on an AFS file. + */ +static int afs_file_mmap(struct file *file, struct vm_area_struct *vma) +{ + struct afs_vnode *vnode = AFS_FS_I(file_inode(file)); + int ret; + + afs_add_open_mmap(vnode); + + ret = generic_file_mmap(file, vma); + if (ret == 0) + vma->vm_ops = &afs_vm_ops; + else + afs_drop_open_mmap(vnode); + return ret; +} + +static void afs_vm_open(struct vm_area_struct *vma) +{ + afs_add_open_mmap(AFS_FS_I(file_inode(vma->vm_file))); +} + +static void afs_vm_close(struct vm_area_struct *vma) +{ + afs_drop_open_mmap(AFS_FS_I(file_inode(vma->vm_file))); +} + +static vm_fault_t afs_vm_map_pages(struct vm_fault *vmf, pgoff_t start_pgoff, pgoff_t end_pgoff) +{ + struct afs_vnode *vnode = AFS_FS_I(file_inode(vmf->vma->vm_file)); + struct afs_file *af = vmf->vma->vm_file->private_data; + + switch (afs_validate(vnode, af->key)) { + case 0: + return filemap_map_pages(vmf, start_pgoff, end_pgoff); + case -ENOMEM: + return VM_FAULT_OOM; + case -EINTR: + case -ERESTARTSYS: + return VM_FAULT_RETRY; + case -ESTALE: + default: + return VM_FAULT_SIGBUS; + } +} + +static ssize_t afs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter) +{ + struct afs_vnode *vnode = AFS_FS_I(file_inode(iocb->ki_filp)); + struct afs_file *af = iocb->ki_filp->private_data; + int ret; + + ret = afs_validate(vnode, af->key); + if (ret < 0) + return ret; + + return generic_file_read_iter(iocb, iter); +} -- cgit v1.2.3