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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
commitcf9610f9116d55c5a66ef9f1faecacabd93a9322 (patch)
tree757a3d280760c654767631cab5ad8af2d86d1848 /fs/fuse/passthrough.c
downloadlinux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.tar.gz
linux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.zip
Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij: "Core changes: - Use the non-blocking mux_state_try_select() in the generic MUX pin control back-end - Free pin maps on pinctrl_generic_to_map() failure in the core helpers New hardware pin control: - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC (this is for the low power audio, LPASS = Low Power Audio SubSystem portions) - Upboard support on top of the Intel pin controller - Apple T6030 and T6031 support (just compatible strings) - Samsung Exynos 8855 SoC - Mediatek MT6858 SoC - Rockchip RK3308B and RV1106 SoCs - Airoha EN7523 and AN7563 SoCs Improvements: - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable - Qualcomm improvements on top of the Qualcomm PDC (power domain controller) irqchip improvements from tglx:s tree - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups - The NPCM8xx driver has been put into shape fixing many pin and group definitions - Some non-urgent Tegra 264 pin assignments are fixed up - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and pin assignments, missing features etc" * tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits) dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema pinctrl: meson: sync some modify from A4 pinctrl: meson: a4: Add input enable pin configuration pinctrl: realtek: rtd1625: remove unused group name spdif_sel pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13 dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema Revert "Merge branch 'ib-rsk7204' into devel" pinctrl: rockchip: Add RV1106 pinctrl support dt-bindings: pinctrl: rockchip: Add RV1106 compatible pinctrl: rockchip: Decode drive strength in the get function pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable pinctrl: airoha: add support of an7563 SoC dt-bindings: pinctrl: airoha: add support of an7563 pin controller pinctrl: airoha: try to find chip scu node by phandle first pinctrl: airoha: add support of en7523 SoC dt-bindings: pinctrl: airoha: add support of en7523 pin controller pinctrl: airoha: an7583: add support for olt pinmux pinctrl: airoha: an7583: add support for pon_alt pinmux pinctrl: airoha: an7583: add support for npu_uart pinmux dt-bindings: pinctrl: airoha: an7583: add missed features ...
Diffstat (limited to 'fs/fuse/passthrough.c')
-rw-r--r--fs/fuse/passthrough.c197
1 files changed, 197 insertions, 0 deletions
diff --git a/fs/fuse/passthrough.c b/fs/fuse/passthrough.c
new file mode 100644
index 000000000..f2d08ac24
--- /dev/null
+++ b/fs/fuse/passthrough.c
@@ -0,0 +1,197 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * FUSE passthrough to backing file.
+ *
+ * Copyright (c) 2023 CTERA Networks.
+ */
+
+#include "fuse_i.h"
+
+#include <linux/file.h>
+#include <linux/backing-file.h>
+#include <linux/splice.h>
+
+static void fuse_file_accessed(struct file *file)
+{
+ struct inode *inode = file_inode(file);
+
+ fuse_invalidate_atime(inode);
+}
+
+static void fuse_passthrough_end_write(struct kiocb *iocb, ssize_t ret)
+{
+ struct inode *inode = file_inode(iocb->ki_filp);
+
+ fuse_write_update_attr(inode, iocb->ki_pos, ret);
+}
+
+ssize_t fuse_passthrough_read_iter(struct kiocb *iocb, struct iov_iter *iter)
+{
+ struct file *file = iocb->ki_filp;
+ struct fuse_file *ff = file->private_data;
+ struct file *backing_file = fuse_file_passthrough(ff);
+ size_t count = iov_iter_count(iter);
+ ssize_t ret;
+ struct backing_file_ctx ctx = {
+ .cred = ff->cred,
+ .accessed = fuse_file_accessed,
+ };
+
+
+ pr_debug("%s: backing_file=0x%p, pos=%lld, len=%zu\n", __func__,
+ backing_file, iocb->ki_pos, count);
+
+ if (!count)
+ return 0;
+
+ ret = backing_file_read_iter(backing_file, iter, iocb, iocb->ki_flags,
+ &ctx);
+
+ return ret;
+}
+
+ssize_t fuse_passthrough_write_iter(struct kiocb *iocb,
+ struct iov_iter *iter)
+{
+ struct file *file = iocb->ki_filp;
+ struct inode *inode = file_inode(file);
+ struct fuse_file *ff = file->private_data;
+ struct file *backing_file = fuse_file_passthrough(ff);
+ size_t count = iov_iter_count(iter);
+ ssize_t ret;
+ struct backing_file_ctx ctx = {
+ .cred = ff->cred,
+ .end_write = fuse_passthrough_end_write,
+ };
+
+ pr_debug("%s: backing_file=0x%p, pos=%lld, len=%zu\n", __func__,
+ backing_file, iocb->ki_pos, count);
+
+ if (!count)
+ return 0;
+
+ inode_lock(inode);
+ ret = backing_file_write_iter(backing_file, iter, iocb, iocb->ki_flags,
+ &ctx);
+ inode_unlock(inode);
+
+ return ret;
+}
+
+ssize_t fuse_passthrough_splice_read(struct file *in, loff_t *ppos,
+ struct pipe_inode_info *pipe,
+ size_t len, unsigned int flags)
+{
+ struct fuse_file *ff = in->private_data;
+ struct file *backing_file = fuse_file_passthrough(ff);
+ struct backing_file_ctx ctx = {
+ .cred = ff->cred,
+ .accessed = fuse_file_accessed,
+ };
+ struct kiocb iocb;
+ ssize_t ret;
+
+ pr_debug("%s: backing_file=0x%p, pos=%lld, len=%zu, flags=0x%x\n", __func__,
+ backing_file, *ppos, len, flags);
+
+ init_sync_kiocb(&iocb, in);
+ iocb.ki_pos = *ppos;
+ ret = backing_file_splice_read(backing_file, &iocb, pipe, len, flags, &ctx);
+ *ppos = iocb.ki_pos;
+
+ return ret;
+}
+
+ssize_t fuse_passthrough_splice_write(struct pipe_inode_info *pipe,
+ struct file *out, loff_t *ppos,
+ size_t len, unsigned int flags)
+{
+ struct fuse_file *ff = out->private_data;
+ struct file *backing_file = fuse_file_passthrough(ff);
+ struct inode *inode = file_inode(out);
+ ssize_t ret;
+ struct backing_file_ctx ctx = {
+ .cred = ff->cred,
+ .end_write = fuse_passthrough_end_write,
+ };
+ struct kiocb iocb;
+
+ pr_debug("%s: backing_file=0x%p, pos=%lld, len=%zu, flags=0x%x\n", __func__,
+ backing_file, *ppos, len, flags);
+
+ inode_lock(inode);
+ init_sync_kiocb(&iocb, out);
+ iocb.ki_pos = *ppos;
+ ret = backing_file_splice_write(pipe, backing_file, &iocb, len, flags, &ctx);
+ *ppos = iocb.ki_pos;
+ inode_unlock(inode);
+
+ return ret;
+}
+
+ssize_t fuse_passthrough_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct fuse_file *ff = file->private_data;
+ struct file *backing_file = fuse_file_passthrough(ff);
+ struct backing_file_ctx ctx = {
+ .cred = ff->cred,
+ .accessed = fuse_file_accessed,
+ };
+
+ pr_debug("%s: backing_file=0x%p, start=%lu, end=%lu\n", __func__,
+ backing_file, vma->vm_start, vma->vm_end);
+
+ return backing_file_mmap(backing_file, vma, &ctx);
+}
+
+/*
+ * Setup passthrough to a backing file.
+ *
+ * Returns an fb object with elevated refcount to be stored in fuse inode.
+ */
+struct fuse_backing *fuse_passthrough_open(struct file *file, int backing_id)
+{
+ struct fuse_file *ff = file->private_data;
+ struct fuse_conn *fc = ff->fm->fc;
+ struct fuse_backing *fb = NULL;
+ struct file *backing_file;
+ int err;
+
+ err = -EINVAL;
+ if (backing_id <= 0)
+ goto out;
+
+ err = -ENOENT;
+ fb = fuse_backing_lookup(fc, backing_id);
+ if (!fb)
+ goto out;
+
+ /* Allocate backing file per fuse file to store fuse path */
+ backing_file = backing_file_open(file, file->f_flags,
+ &fb->file->f_path, fb->cred);
+ err = PTR_ERR(backing_file);
+ if (IS_ERR(backing_file)) {
+ fuse_backing_put(fb);
+ goto out;
+ }
+
+ err = 0;
+ ff->passthrough = backing_file;
+ ff->cred = get_cred(fb->cred);
+out:
+ pr_debug("%s: backing_id=%d, fb=0x%p, backing_file=0x%p, err=%i\n", __func__,
+ backing_id, fb, ff->passthrough, err);
+
+ return err ? ERR_PTR(err) : fb;
+}
+
+void fuse_passthrough_release(struct fuse_file *ff, struct fuse_backing *fb)
+{
+ pr_debug("%s: fb=0x%p, backing_file=0x%p\n", __func__,
+ fb, ff->passthrough);
+
+ fput(ff->passthrough);
+ ff->passthrough = NULL;
+ put_cred(ff->cred);
+ ff->cred = NULL;
+}