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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-24 08:46:03 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-24 08:46:03 -0700 |
| commit | cf9610f9116d55c5a66ef9f1faecacabd93a9322 (patch) | |
| tree | 757a3d280760c654767631cab5ad8af2d86d1848 /fs/backing-file.c | |
| download | linux-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/backing-file.c')
| -rw-r--r-- | fs/backing-file.c | 366 |
1 files changed, 366 insertions, 0 deletions
diff --git a/fs/backing-file.c b/fs/backing-file.c new file mode 100644 index 000000000..cc101143f --- /dev/null +++ b/fs/backing-file.c @@ -0,0 +1,366 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Common helpers for stackable filesystems and backing files. + * + * Forked from fs/overlayfs/file.c. + * + * Copyright (C) 2017 Red Hat, Inc. + * Copyright (C) 2023 CTERA Networks. + */ + +#include <linux/fs.h> +#include <linux/backing-file.h> +#include <linux/splice.h> +#include <linux/mm.h> +#include <linux/security.h> + +#include "internal.h" + +/** + * backing_file_open - open a backing file for kernel internal use + * @user_file: file the user requested to open + * @flags: open flags + * @real_path: path of the backing file + * @cred: credentials for open + * + * Open a backing file for a stackable filesystem (e.g., overlayfs). + * @user_file->f_path may be on the stackable filesystem and @real_path + * on the underlying filesystem. In this case, we want to be able to + * return the path of the stackable filesystem. This is done by + * embedding the returned file into a container structure that also + * stores the stacked file's path, which can be retrieved using + * backing_file_user_path(). + */ +struct file *backing_file_open(const struct file *user_file, int flags, + const struct path *real_path, + const struct cred *cred) +{ + const struct path *user_path = file_user_path(user_file); + struct file *f; + int error; + + f = alloc_empty_backing_file(flags, cred, user_file); + if (IS_ERR(f)) + return f; + + path_get(user_path); + backing_file_set_user_path(f, user_path); + error = vfs_open(real_path, f); + if (error) { + fput(f); + f = ERR_PTR(error); + } + + return f; +} +EXPORT_SYMBOL_GPL(backing_file_open); + +struct file *backing_tmpfile_open(const struct file *user_file, int flags, + const struct path *real_parentpath, + umode_t mode, const struct cred *cred) +{ + struct mnt_idmap *real_idmap = mnt_idmap(real_parentpath->mnt); + const struct path *user_path = &user_file->f_path; + struct file *f; + int error; + + f = alloc_empty_backing_file(flags, cred, user_file); + if (IS_ERR(f)) + return f; + + path_get(user_path); + backing_file_set_user_path(f, user_path); + error = vfs_tmpfile(real_idmap, real_parentpath, f, mode); + if (error) { + fput(f); + f = ERR_PTR(error); + } + return f; +} +EXPORT_SYMBOL(backing_tmpfile_open); + +struct backing_aio { + struct kiocb iocb; + refcount_t ref; + struct kiocb *orig_iocb; + /* used for aio completion */ + void (*end_write)(struct kiocb *iocb, ssize_t); + struct work_struct work; + long res; +}; + +static struct kmem_cache *backing_aio_cachep; + +#define BACKING_IOCB_MASK \ + (IOCB_NOWAIT | IOCB_HIPRI | IOCB_DSYNC | IOCB_SYNC | IOCB_APPEND) + +static rwf_t iocb_to_rw_flags(int flags) +{ + return (__force rwf_t)(flags & BACKING_IOCB_MASK); +} + +static void backing_aio_put(struct backing_aio *aio) +{ + if (refcount_dec_and_test(&aio->ref)) { + fput(aio->iocb.ki_filp); + kmem_cache_free(backing_aio_cachep, aio); + } +} + +static void backing_aio_cleanup(struct backing_aio *aio, long res) +{ + struct kiocb *iocb = &aio->iocb; + struct kiocb *orig_iocb = aio->orig_iocb; + + orig_iocb->ki_pos = iocb->ki_pos; + if (aio->end_write) + aio->end_write(orig_iocb, res); + + backing_aio_put(aio); +} + +static void backing_aio_rw_complete(struct kiocb *iocb, long res) +{ + struct backing_aio *aio = container_of(iocb, struct backing_aio, iocb); + struct kiocb *orig_iocb = aio->orig_iocb; + + if (iocb->ki_flags & IOCB_WRITE) + kiocb_end_write(iocb); + + backing_aio_cleanup(aio, res); + orig_iocb->ki_complete(orig_iocb, res); +} + +static void backing_aio_complete_work(struct work_struct *work) +{ + struct backing_aio *aio = container_of(work, struct backing_aio, work); + + backing_aio_rw_complete(&aio->iocb, aio->res); +} + +static void backing_aio_queue_completion(struct kiocb *iocb, long res) +{ + struct backing_aio *aio = container_of(iocb, struct backing_aio, iocb); + + /* + * Punt to a work queue to serialize updates of mtime/size. + */ + aio->res = res; + INIT_WORK(&aio->work, backing_aio_complete_work); + queue_work(file_inode(aio->orig_iocb->ki_filp)->i_sb->s_dio_done_wq, + &aio->work); +} + +static int backing_aio_init_wq(struct kiocb *iocb) +{ + struct super_block *sb = file_inode(iocb->ki_filp)->i_sb; + + if (sb->s_dio_done_wq) + return 0; + + return sb_init_dio_done_wq(sb); +} + +static int do_backing_file_read_iter(struct file *file, struct iov_iter *iter, + struct kiocb *iocb, int flags) +{ + struct backing_aio *aio = NULL; + int ret; + + if (is_sync_kiocb(iocb)) { + rwf_t rwf = iocb_to_rw_flags(flags); + + return vfs_iter_read(file, iter, &iocb->ki_pos, rwf); + } + + aio = kmem_cache_zalloc(backing_aio_cachep, GFP_KERNEL); + if (!aio) + return -ENOMEM; + + aio->orig_iocb = iocb; + kiocb_clone(&aio->iocb, iocb, get_file(file)); + aio->iocb.ki_complete = backing_aio_rw_complete; + refcount_set(&aio->ref, 2); + ret = vfs_iocb_iter_read(file, &aio->iocb, iter); + backing_aio_put(aio); + if (ret != -EIOCBQUEUED) + backing_aio_cleanup(aio, ret); + return ret; +} + +ssize_t backing_file_read_iter(struct file *file, struct iov_iter *iter, + struct kiocb *iocb, int flags, + struct backing_file_ctx *ctx) +{ + ssize_t ret; + + if (WARN_ON_ONCE(!(file->f_mode & FMODE_BACKING))) + return -EIO; + + if (!iov_iter_count(iter)) + return 0; + + if (iocb->ki_flags & IOCB_DIRECT && + !(file->f_mode & FMODE_CAN_ODIRECT)) + return -EINVAL; + + scoped_with_creds(ctx->cred) + ret = do_backing_file_read_iter(file, iter, iocb, flags); + + if (ctx->accessed) + ctx->accessed(iocb->ki_filp); + + return ret; +} +EXPORT_SYMBOL_GPL(backing_file_read_iter); + +static int do_backing_file_write_iter(struct file *file, struct iov_iter *iter, + struct kiocb *iocb, int flags, + void (*end_write)(struct kiocb *, ssize_t)) +{ + struct backing_aio *aio; + int ret; + + if (is_sync_kiocb(iocb)) { + rwf_t rwf = iocb_to_rw_flags(flags); + + ret = vfs_iter_write(file, iter, &iocb->ki_pos, rwf); + if (end_write) + end_write(iocb, ret); + return ret; + } + + ret = backing_aio_init_wq(iocb); + if (ret) + return ret; + + aio = kmem_cache_zalloc(backing_aio_cachep, GFP_KERNEL); + if (!aio) + return -ENOMEM; + + aio->orig_iocb = iocb; + aio->end_write = end_write; + kiocb_clone(&aio->iocb, iocb, get_file(file)); + aio->iocb.ki_flags = flags; + aio->iocb.ki_complete = backing_aio_queue_completion; + refcount_set(&aio->ref, 2); + ret = vfs_iocb_iter_write(file, &aio->iocb, iter); + backing_aio_put(aio); + if (ret != -EIOCBQUEUED) + backing_aio_cleanup(aio, ret); + return ret; +} + +ssize_t backing_file_write_iter(struct file *file, struct iov_iter *iter, + struct kiocb *iocb, int flags, + struct backing_file_ctx *ctx) +{ + ssize_t ret; + + if (WARN_ON_ONCE(!(file->f_mode & FMODE_BACKING))) + return -EIO; + + if (!iov_iter_count(iter)) + return 0; + + ret = file_remove_privs(iocb->ki_filp); + if (ret) + return ret; + + if (iocb->ki_flags & IOCB_DIRECT && + !(file->f_mode & FMODE_CAN_ODIRECT)) + return -EINVAL; + + scoped_with_creds(ctx->cred) + return do_backing_file_write_iter(file, iter, iocb, flags, ctx->end_write); +} +EXPORT_SYMBOL_GPL(backing_file_write_iter); + +ssize_t backing_file_splice_read(struct file *in, struct kiocb *iocb, + struct pipe_inode_info *pipe, size_t len, + unsigned int flags, + struct backing_file_ctx *ctx) +{ + ssize_t ret; + + if (WARN_ON_ONCE(!(in->f_mode & FMODE_BACKING))) + return -EIO; + + scoped_with_creds(ctx->cred) + ret = vfs_splice_read(in, &iocb->ki_pos, pipe, len, flags); + + if (ctx->accessed) + ctx->accessed(iocb->ki_filp); + + return ret; +} +EXPORT_SYMBOL_GPL(backing_file_splice_read); + +ssize_t backing_file_splice_write(struct pipe_inode_info *pipe, + struct file *out, struct kiocb *iocb, + size_t len, unsigned int flags, + struct backing_file_ctx *ctx) +{ + ssize_t ret; + + if (WARN_ON_ONCE(!(out->f_mode & FMODE_BACKING))) + return -EIO; + + if (!out->f_op->splice_write) + return -EINVAL; + + ret = file_remove_privs(iocb->ki_filp); + if (ret) + return ret; + + scoped_with_creds(ctx->cred) { + file_start_write(out); + ret = out->f_op->splice_write(pipe, out, &iocb->ki_pos, len, flags); + file_end_write(out); + } + + if (ctx->end_write) + ctx->end_write(iocb, ret); + + return ret; +} +EXPORT_SYMBOL_GPL(backing_file_splice_write); + +int backing_file_mmap(struct file *file, struct vm_area_struct *vma, + struct backing_file_ctx *ctx) +{ + struct file *user_file = vma->vm_file; + int ret; + + if (WARN_ON_ONCE(!(file->f_mode & FMODE_BACKING))) + return -EIO; + + if (!can_mmap_file(file)) + return -ENODEV; + + vma_set_file(vma, file); + + scoped_with_creds(ctx->cred) { + ret = security_mmap_backing_file(vma, file, user_file); + if (ret) + return ret; + + ret = vfs_mmap(vma->vm_file, vma); + } + + if (ctx->accessed) + ctx->accessed(user_file); + + return ret; +} +EXPORT_SYMBOL_GPL(backing_file_mmap); + +static int __init backing_aio_init(void) +{ + backing_aio_cachep = KMEM_CACHE(backing_aio, SLAB_HWCACHE_ALIGN); + if (!backing_aio_cachep) + return -ENOMEM; + + return 0; +} +fs_initcall(backing_aio_init); |
