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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /fs/afs/dir_silly.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'fs/afs/dir_silly.c')
-rw-r--r--fs/afs/dir_silly.c289
1 files changed, 289 insertions, 0 deletions
diff --git a/fs/afs/dir_silly.c b/fs/afs/dir_silly.c
new file mode 100644
index 000000000..982bb6ec1
--- /dev/null
+++ b/fs/afs/dir_silly.c
@@ -0,0 +1,289 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* AFS silly rename handling
+ *
+ * Copyright (C) 2019 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ * - Derived from NFS's sillyrename.
+ */
+
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/namei.h>
+#include <linux/fsnotify.h>
+#include "internal.h"
+
+static void afs_silly_rename_success(struct afs_operation *op)
+{
+ _enter("op=%08x", op->debug_id);
+
+ afs_check_dir_conflict(op, &op->file[0]);
+ afs_vnode_commit_status(op, &op->file[0]);
+}
+
+static void afs_silly_rename_edit_dir(struct afs_operation *op)
+{
+ struct afs_vnode_param *dvp = &op->file[0];
+ struct afs_vnode *dvnode = dvp->vnode;
+ struct afs_vnode *vnode = AFS_FS_I(d_inode(op->dentry));
+ struct dentry *old = op->dentry;
+ struct dentry *new = op->dentry_2;
+
+ spin_lock(&old->d_lock);
+ old->d_flags |= DCACHE_NFSFS_RENAMED;
+ spin_unlock(&old->d_lock);
+ if (dvnode->silly_key != op->key) {
+ key_put(dvnode->silly_key);
+ dvnode->silly_key = key_get(op->key);
+ }
+
+ down_write(&dvnode->validate_lock);
+ if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) &&
+ dvnode->status.data_version == dvp->dv_before + dvp->dv_delta) {
+ afs_edit_dir_remove(dvnode, &old->d_name,
+ afs_edit_dir_for_silly_0);
+ afs_edit_dir_add(dvnode, &new->d_name,
+ &vnode->fid, afs_edit_dir_for_silly_1);
+ }
+ up_write(&dvnode->validate_lock);
+}
+
+static const struct afs_operation_ops afs_silly_rename_operation = {
+ .issue_afs_rpc = afs_fs_rename,
+ .issue_yfs_rpc = yfs_fs_rename,
+ .success = afs_silly_rename_success,
+ .edit_dir = afs_silly_rename_edit_dir,
+};
+
+/*
+ * Actually perform the silly rename step.
+ */
+static int afs_do_silly_rename(struct afs_vnode *dvnode, struct afs_vnode *vnode,
+ struct dentry *old, struct dentry *new,
+ struct key *key)
+{
+ struct afs_operation *op;
+
+ _enter("%pd,%pd", old, new);
+
+ op = afs_alloc_operation(key, dvnode->volume);
+ if (IS_ERR(op))
+ return PTR_ERR(op);
+
+ op->more_files = kvzalloc_objs(struct afs_vnode_param, 2);
+ if (!op->more_files) {
+ afs_put_operation(op);
+ return -ENOMEM;
+ }
+
+ afs_op_set_vnode(op, 0, dvnode);
+ afs_op_set_vnode(op, 1, dvnode);
+ op->file[0].dv_delta = 1;
+ op->file[1].dv_delta = 1;
+ op->file[0].modification = true;
+ op->file[1].modification = true;
+ op->file[0].update_ctime = true;
+ op->file[1].update_ctime = true;
+ op->more_files[0].vnode = AFS_FS_I(d_inode(old));
+ op->more_files[0].speculative = true;
+ op->more_files[1].vnode = AFS_FS_I(d_inode(new));
+ op->more_files[1].speculative = true;
+ op->nr_files = 4;
+
+ op->dentry = old;
+ op->dentry_2 = new;
+ op->ops = &afs_silly_rename_operation;
+
+ trace_afs_silly_rename(vnode, false);
+ return afs_do_sync_operation(op);
+}
+
+/*
+ * Perform silly-rename of a dentry.
+ *
+ * AFS is stateless and the server doesn't know when the client is holding a
+ * file open. To prevent application problems when a file is unlinked while
+ * it's still open, the client performs a "silly-rename". That is, it renames
+ * the file to a hidden file in the same directory, and only performs the
+ * unlink once the last reference to it is put.
+ *
+ * The final cleanup is done during dentry_iput.
+ */
+int afs_sillyrename(struct afs_vnode *dvnode, struct afs_vnode *vnode,
+ struct dentry *dentry, struct key *key)
+{
+ static unsigned int sillycounter;
+ struct dentry *sdentry = NULL;
+ unsigned char silly[16];
+ int ret = -EBUSY;
+
+ _enter("");
+
+ /* We don't allow a dentry to be silly-renamed twice. */
+ if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
+ return -EBUSY;
+
+ sdentry = NULL;
+ do {
+ dput(sdentry);
+ sillycounter++;
+
+ /* Create a silly name. Note that the ".__afs" prefix is
+ * understood by the salvager and must not be changed.
+ */
+ scnprintf(silly, sizeof(silly), ".__afs%04X", sillycounter);
+ sdentry = lookup_noperm(&QSTR(silly), dentry->d_parent);
+
+ /* N.B. Better to return EBUSY here ... it could be dangerous
+ * to delete the file while it's in use.
+ */
+ if (IS_ERR(sdentry))
+ goto out;
+ } while (!d_is_negative(sdentry));
+
+ ihold(&vnode->netfs.inode);
+
+ ret = afs_do_silly_rename(dvnode, vnode, dentry, sdentry, key);
+ switch (ret) {
+ case 0:
+ /* The rename succeeded. */
+ set_bit(AFS_VNODE_SILLY_DELETED, &vnode->flags);
+ d_move(dentry, sdentry);
+ break;
+ case -ERESTARTSYS:
+ /* The result of the rename is unknown. Play it safe by forcing
+ * a new lookup.
+ */
+ d_drop(dentry);
+ d_drop(sdentry);
+ }
+
+ iput(&vnode->netfs.inode);
+ dput(sdentry);
+out:
+ _leave(" = %d", ret);
+ return ret;
+}
+
+static void afs_silly_unlink_success(struct afs_operation *op)
+{
+ _enter("op=%08x", op->debug_id);
+ afs_check_dir_conflict(op, &op->file[0]);
+ afs_vnode_commit_status(op, &op->file[0]);
+ afs_vnode_commit_status(op, &op->file[1]);
+ afs_update_dentry_version(op, &op->file[0], op->dentry);
+}
+
+static void afs_silly_unlink_edit_dir(struct afs_operation *op)
+{
+ struct afs_vnode_param *dvp = &op->file[0];
+ struct afs_vnode *dvnode = dvp->vnode;
+
+ _enter("op=%08x", op->debug_id);
+ down_write(&dvnode->validate_lock);
+ if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) &&
+ dvnode->status.data_version == dvp->dv_before + dvp->dv_delta)
+ afs_edit_dir_remove(dvnode, &op->dentry->d_name,
+ afs_edit_dir_for_unlink);
+ up_write(&dvnode->validate_lock);
+}
+
+static const struct afs_operation_ops afs_silly_unlink_operation = {
+ .issue_afs_rpc = afs_fs_remove_file,
+ .issue_yfs_rpc = yfs_fs_remove_file,
+ .success = afs_silly_unlink_success,
+ .aborted = afs_check_for_remote_deletion,
+ .edit_dir = afs_silly_unlink_edit_dir,
+};
+
+/*
+ * Tell the server to remove a sillyrename file.
+ */
+static int afs_do_silly_unlink(struct afs_vnode *dvnode, struct afs_vnode *vnode,
+ struct dentry *dentry, struct key *key)
+{
+ struct afs_operation *op;
+
+ _enter("");
+
+ op = afs_alloc_operation(NULL, dvnode->volume);
+ if (IS_ERR(op))
+ return PTR_ERR(op);
+
+ afs_op_set_vnode(op, 0, dvnode);
+ afs_op_set_vnode(op, 1, vnode);
+ op->file[0].dv_delta = 1;
+ op->file[0].modification = true;
+ op->file[0].update_ctime = true;
+ op->file[1].op_unlinked = true;
+ op->file[1].update_ctime = true;
+
+ op->dentry = dentry;
+ op->ops = &afs_silly_unlink_operation;
+
+ trace_afs_silly_rename(vnode, true);
+ afs_begin_vnode_operation(op);
+ afs_wait_for_operation(op);
+
+ /* If there was a conflict with a third party, check the status of the
+ * unlinked vnode.
+ */
+ if (op->cumul_error.error == 0 && (op->flags & AFS_OPERATION_DIR_CONFLICT)) {
+ op->file[1].update_ctime = false;
+ op->fetch_status.which = 1;
+ op->ops = &afs_fetch_status_operation;
+ afs_begin_vnode_operation(op);
+ afs_wait_for_operation(op);
+ }
+
+ return afs_put_operation(op);
+}
+
+/*
+ * Remove sillyrename file on iput.
+ */
+int afs_silly_iput(struct dentry *dentry, struct inode *inode)
+{
+ struct afs_vnode *dvnode = AFS_FS_I(d_inode(dentry->d_parent));
+ struct afs_vnode *vnode = AFS_FS_I(inode);
+ struct dentry *alias;
+ int ret;
+
+ _enter("%p{%pd},%llx", dentry, dentry, vnode->fid.vnode);
+
+ down_read(&dvnode->rmdir_lock);
+
+ alias = d_alloc_parallel(dentry->d_parent, &dentry->d_name);
+ if (IS_ERR(alias)) {
+ up_read(&dvnode->rmdir_lock);
+ return 0;
+ }
+
+ if (!d_in_lookup(alias)) {
+ /* We raced with lookup... See if we need to transfer the
+ * sillyrename information to the aliased dentry.
+ */
+ ret = 0;
+ spin_lock(&alias->d_lock);
+ if (d_really_is_positive(alias) &&
+ !(alias->d_flags & DCACHE_NFSFS_RENAMED)) {
+ alias->d_flags |= DCACHE_NFSFS_RENAMED;
+ ret = 1;
+ }
+ spin_unlock(&alias->d_lock);
+ up_read(&dvnode->rmdir_lock);
+ dput(alias);
+ return ret;
+ }
+
+ /* Stop lock-release from complaining. */
+ spin_lock(&vnode->lock);
+ vnode->lock_state = AFS_VNODE_LOCK_DELETED;
+ trace_afs_flock_ev(vnode, NULL, afs_flock_silly_delete, 0);
+ spin_unlock(&vnode->lock);
+
+ afs_do_silly_unlink(dvnode, vnode, dentry, dvnode->silly_key);
+ up_read(&dvnode->rmdir_lock);
+ d_lookup_done(alias);
+ dput(alias);
+ return 1;
+}