From 3f7bb066b4760e2523e698d39a94369ed89ed644 Mon Sep 17 00:00:00 2001 From: Bruce Ashfield Date: Thu, 21 Sep 2023 17:49:39 -0400 Subject: [PATCH 3/8] aufs6: mmap Signed-off-by: Bruce Ashfield --- fs/proc/base.c | 2 +- fs/proc/nommu.c | 5 ++- fs/proc/task_mmu.c | 7 +++- fs/proc/task_nommu.c | 5 ++- include/linux/mm.h | 37 +++++++++++++++++ include/linux/mm_types.h | 6 +++ kernel/fork.c | 2 +- mm/Makefile | 1 + mm/filemap.c | 2 +- mm/mmap.c | 41 +++++++++++++++---- mm/nommu.c | 10 ++--- mm/prfile.c | 86 ++++++++++++++++++++++++++++++++++++++++ 12 files changed, 185 insertions(+), 19 deletions(-) create mode 100644 mm/prfile.c diff --git a/fs/proc/base.c b/fs/proc/base.c index ffd54617c354..29ec720c8038 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -2218,7 +2218,7 @@ static int map_files_get_link(struct dentry *dentry, struct path *path) rc = -ENOENT; vma = find_exact_vma(mm, vm_start, vm_end); if (vma && vma->vm_file) { - *path = vma->vm_file->f_path; + *path = vma_pr_or_file(vma)->f_path; path_get(path); rc = 0; } diff --git a/fs/proc/nommu.c b/fs/proc/nommu.c index 4d3493579458..42edd9a42c78 100644 --- a/fs/proc/nommu.c +++ b/fs/proc/nommu.c @@ -39,7 +39,10 @@ static int nommu_region_show(struct seq_file *m, struct vm_region *region) file = region->vm_file; if (file) { - struct inode *inode = file_inode(region->vm_file); + struct inode *inode; + + file = vmr_pr_or_file(region); + inode = file_inode(file); dev = inode->i_sb->s_dev; ino = inode->i_ino; } diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 3dd5be96691b..40d9d970b308 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -271,7 +271,10 @@ show_map_vma(struct seq_file *m, struct vm_area_struct *vma) const char *name = NULL; if (file) { - struct inode *inode = file_inode(vma->vm_file); + struct inode *inode; + + file = vma_pr_or_file(vma); + inode = file_inode(file); dev = inode->i_sb->s_dev; ino = inode->i_ino; pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT; @@ -1943,7 +1946,7 @@ static int show_numa_map(struct seq_file *m, void *v) struct proc_maps_private *proc_priv = &numa_priv->proc_maps; struct vm_area_struct *vma = v; struct numa_maps *md = &numa_priv->md; - struct file *file = vma->vm_file; + struct file *file = vma_pr_or_file(vma); struct mm_struct *mm = vma->vm_mm; struct mempolicy *pol; char buffer[64]; diff --git a/fs/proc/task_nommu.c b/fs/proc/task_nommu.c index a8ac0dd8041e..9fca456e2259 100644 --- a/fs/proc/task_nommu.c +++ b/fs/proc/task_nommu.c @@ -137,7 +137,10 @@ static int nommu_vma_show(struct seq_file *m, struct vm_area_struct *vma) file = vma->vm_file; if (file) { - struct inode *inode = file_inode(vma->vm_file); + struct inode *inode; + + file = vma_pr_or_file(vma); + inode = file_inode(file); dev = inode->i_sb->s_dev; ino = inode->i_ino; pgoff = (loff_t)vma->vm_pgoff << PAGE_SHIFT; diff --git a/include/linux/mm.h b/include/linux/mm.h index bf5d0b1b16f4..7369d46578e0 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2409,6 +2409,43 @@ static inline void unmap_shared_mapping_range(struct address_space *mapping, static inline struct vm_area_struct *vma_lookup(struct mm_struct *mm, unsigned long addr); +#if 1 /* IS_ENABLED(CONFIG_AUFS_FS) */ +extern void vma_do_file_update_time(struct vm_area_struct *, const char[], int); +extern struct file *vma_do_pr_or_file(struct vm_area_struct *, const char[], + int); +extern void vma_do_get_file(struct vm_area_struct *, const char[], int); +extern void vma_do_fput(struct vm_area_struct *, const char[], int); + +#define vma_file_update_time(vma) vma_do_file_update_time(vma, __func__, \ + __LINE__) +#define vma_pr_or_file(vma) vma_do_pr_or_file(vma, __func__, \ + __LINE__) +#define vma_get_file(vma) vma_do_get_file(vma, __func__, __LINE__) +#define vma_fput(vma) vma_do_fput(vma, __func__, __LINE__) + +#ifndef CONFIG_MMU +extern struct file *vmr_do_pr_or_file(struct vm_region *, const char[], int); +extern void vmr_do_fput(struct vm_region *, const char[], int); + +#define vmr_pr_or_file(region) vmr_do_pr_or_file(region, __func__, \ + __LINE__) +#define vmr_fput(region) vmr_do_fput(region, __func__, __LINE__) +#endif /* !CONFIG_MMU */ + +#else + +#define vma_file_update_time(vma) file_update_time((vma)->vm_file) +#define vma_pr_or_file(vma) (vma)->vm_file +#define vma_get_file(vma) get_file((vma)->vm_file) +#define vma_fput(vma) fput((vma)->vm_file) + +#ifndef CONFIG_MMU +#define vmr_pr_or_file(region) (region)->vm_file +#define vmr_fput(region) fput((region)->vm_file) +#endif /* !CONFIG_MMU */ + +#endif /* CONFIG_AUFS_FS */ + extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, unsigned int gup_flags); extern int access_remote_vm(struct mm_struct *mm, unsigned long addr, diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 36c5b43999e6..13616a9af017 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -524,6 +524,9 @@ struct vm_region { unsigned long vm_top; /* region allocated to here */ unsigned long vm_pgoff; /* the offset in vm_file corresponding to vm_start */ struct file *vm_file; /* the backing file or NULL */ +#if 1 /* IS_ENABLED(CONFIG_AUFS_FS) */ + struct file *vm_prfile; /* the virtual backing file or NULL */ +#endif int vm_usage; /* region usage count (access under nommu_region_sem) */ bool vm_icache_flushed : 1; /* true if the icache has been flushed for @@ -637,6 +640,9 @@ struct vm_area_struct { unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE units */ struct file * vm_file; /* File we map to (can be NULL). */ +#if 1 /* IS_ENABLED(CONFIG_AUFS_FS) */ + struct file *vm_prfile; /* shadow of vm_file */ +#endif void * vm_private_data; /* was vm_pte (shared mem) */ #ifdef CONFIG_ANON_VMA_NAME diff --git a/kernel/fork.c b/kernel/fork.c index 3b6d20dfb9a8..ccad0325cfa9 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -731,7 +731,7 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, if (file) { struct address_space *mapping = file->f_mapping; - get_file(file); + vma_get_file(tmp); i_mmap_lock_write(mapping); if (tmp->vm_flags & VM_SHARED) mapping_allow_writable(mapping); diff --git a/mm/Makefile b/mm/Makefile index ec65984e2ade..2b291b2959a6 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -138,3 +138,4 @@ obj-$(CONFIG_IO_MAPPING) += io-mapping.o obj-$(CONFIG_HAVE_BOOTMEM_INFO_NODE) += bootmem_info.o obj-$(CONFIG_GENERIC_IOREMAP) += ioremap.o obj-$(CONFIG_SHRINKER_DEBUG) += shrinker_debug.o +obj-y += prfile.o diff --git a/mm/filemap.c b/mm/filemap.c index 582f5317ff71..c024ebb30073 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -3599,7 +3599,7 @@ vm_fault_t filemap_page_mkwrite(struct vm_fault *vmf) vm_fault_t ret = VM_FAULT_LOCKED; sb_start_pagefault(mapping->host->i_sb); - file_update_time(vmf->vma->vm_file); + vma_file_update_time(vmf->vma); folio_lock(folio); if (folio->mapping != mapping) { folio_unlock(folio); diff --git a/mm/mmap.c b/mm/mmap.c index b56a7f0c9f85..0a0f3d5f558d 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -140,7 +140,7 @@ static void remove_vma(struct vm_area_struct *vma, bool unreachable) if (vma->vm_ops && vma->vm_ops->close) vma->vm_ops->close(vma); if (vma->vm_file) - fput(vma->vm_file); + vma_fput(vma); mpol_put(vma_policy(vma)); if (unreachable) __vm_area_free(vma); @@ -554,7 +554,7 @@ static inline void vma_complete(struct vma_prepare *vp, if (vp->file) { uprobe_munmap(vp->remove, vp->remove->vm_start, vp->remove->vm_end); - fput(vp->file); + vma_fput(vp->vma); } if (vp->remove->anon_vma) anon_vma_merge(vp->vma, vp->remove); @@ -2364,7 +2364,7 @@ int __split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma, goto out_free_mpol; if (new->vm_file) - get_file(new->vm_file); + vma_get_file(new); if (new->vm_ops && new->vm_ops->open) new->vm_ops->open(new); @@ -2781,7 +2781,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr, * and cause general protection fault * ultimately. */ - fput(vma->vm_file); + vma_fput(vma); vm_area_free(vma); vma = merge; /* Update vm_flags to pick up the change. */ @@ -2876,7 +2876,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr, if (file || vma->vm_file) { unmap_and_free_vma: - fput(vma->vm_file); + vma_fput(vma); vma->vm_file = NULL; vma_iter_set(&vmi, vma->vm_end); @@ -2938,6 +2938,9 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size, unsigned long populate = 0; unsigned long ret = -EINVAL; struct file *file; +#if 1 /* IS_ENABLED(CONFIG_AUFS_FS) */ + struct file *prfile; +#endif pr_warn_once("%s (%d) uses deprecated remap_file_pages() syscall. See Documentation/mm/remap_file_pages.rst.\n", current->comm, current->pid); @@ -2996,10 +2999,34 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size, if (vma->vm_flags & VM_LOCKED) flags |= MAP_LOCKED; +#if 1 /* IS_ENABLED(CONFIG_AUFS_FS) */ + vma_get_file(vma); + file = vma->vm_file; + prfile = vma->vm_prfile; + ret = do_mmap(vma->vm_file, start, size, + prot, flags, pgoff, &populate, NULL); + if (!IS_ERR_VALUE(ret) && file && prfile) { + struct vm_area_struct *new_vma; + + new_vma = find_vma(mm, ret); + if (!new_vma->vm_prfile) + new_vma->vm_prfile = prfile; + if (prfile) + get_file(prfile); + } + /* + * two fput()s instead of vma_fput(vma), + * coz vma may not be available anymore. + */ + fput(file); + if (prfile) + fput(prfile); +#else file = get_file(vma->vm_file); ret = do_mmap(vma->vm_file, start, size, prot, flags, 0, pgoff, &populate, NULL); fput(file); +#endif /* CONFIG_AUFS_FS */ out: mmap_write_unlock(mm); if (populate) @@ -3350,7 +3377,7 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap, if (anon_vma_clone(new_vma, vma)) goto out_free_mempol; if (new_vma->vm_file) - get_file(new_vma->vm_file); + vma_get_file(new_vma); if (new_vma->vm_ops && new_vma->vm_ops->open) new_vma->vm_ops->open(new_vma); if (vma_link(mm, new_vma)) @@ -3364,7 +3391,7 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap, new_vma->vm_ops->close(new_vma); if (new_vma->vm_file) - fput(new_vma->vm_file); + vma_fput(new_vma); unlink_anon_vmas(new_vma); out_free_mempol: diff --git a/mm/nommu.c b/mm/nommu.c index 7f9e9e5a0e12..69663f2bd4c4 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -523,7 +523,7 @@ static void __put_nommu_region(struct vm_region *region) up_write(&nommu_region_sem); if (region->vm_file) - fput(region->vm_file); + vmr_fput(region); /* IO memory and memory shared directly out of the pagecache * from ramfs/tmpfs mustn't be released here */ @@ -603,7 +603,7 @@ static void delete_vma(struct mm_struct *mm, struct vm_area_struct *vma) if (vma->vm_ops && vma->vm_ops->close) vma->vm_ops->close(vma); if (vma->vm_file) - fput(vma->vm_file); + vma_fput(vma); put_nommu_region(vma->vm_region); vm_area_free(vma); } @@ -1135,7 +1135,7 @@ unsigned long do_mmap(struct file *file, goto error_just_free; } } - fput(region->vm_file); + vmr_fput(region); kmem_cache_free(vm_region_jar, region); region = pregion; result = start; @@ -1221,10 +1221,10 @@ unsigned long do_mmap(struct file *file, error: vma_iter_free(&vmi); if (region->vm_file) - fput(region->vm_file); + vmr_fput(region); kmem_cache_free(vm_region_jar, region); if (vma->vm_file) - fput(vma->vm_file); + vma_fput(vma); vm_area_free(vma); return ret; diff --git a/mm/prfile.c b/mm/prfile.c new file mode 100644 index 000000000000..8f820a235364 --- /dev/null +++ b/mm/prfile.c @@ -0,0 +1,86 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Mainly for aufs which mmap(2) different file and wants to print different + * path in /proc/PID/maps. + * Call these functions via macros defined in linux/mm.h. + * + * See Documentation/filesystems/aufs/design/06mmap.txt + * + * Copyright (c) 2014-2022 Junjro R. Okajima + * Copyright (c) 2014 Ian Campbell + */ + +#include +#include +#include + +/* #define PRFILE_TRACE */ +static inline void prfile_trace(struct file *f, struct file *pr, + const char func[], int line, const char func2[]) +{ +#ifdef PRFILE_TRACE + if (pr) + pr_info("%s:%d: %s, %pD2\n", func, line, func2, f); +#endif +} + +void vma_do_file_update_time(struct vm_area_struct *vma, const char func[], + int line) +{ + struct file *f = vma->vm_file, *pr = vma->vm_prfile; + + prfile_trace(f, pr, func, line, __func__); + file_update_time(f); + if (f && pr) + file_update_time(pr); +} + +struct file *vma_do_pr_or_file(struct vm_area_struct *vma, const char func[], + int line) +{ + struct file *f = vma->vm_file, *pr = vma->vm_prfile; + + prfile_trace(f, pr, func, line, __func__); + return (f && pr) ? pr : f; +} + +void vma_do_get_file(struct vm_area_struct *vma, const char func[], int line) +{ + struct file *f = vma->vm_file, *pr = vma->vm_prfile; + + prfile_trace(f, pr, func, line, __func__); + get_file(f); + if (f && pr) + get_file(pr); +} + +void vma_do_fput(struct vm_area_struct *vma, const char func[], int line) +{ + struct file *f = vma->vm_file, *pr = vma->vm_prfile; + + prfile_trace(f, pr, func, line, __func__); + fput(f); + if (f && pr) + fput(pr); +} + +#ifndef CONFIG_MMU +struct file *vmr_do_pr_or_file(struct vm_region *region, const char func[], + int line) +{ + struct file *f = region->vm_file, *pr = region->vm_prfile; + + prfile_trace(f, pr, func, line, __func__); + return (f && pr) ? pr : f; +} + +void vmr_do_fput(struct vm_region *region, const char func[], int line) +{ + struct file *f = region->vm_file, *pr = region->vm_prfile; + + prfile_trace(f, pr, func, line, __func__); + fput(f); + if (f && pr) + fput(pr); +} +#endif /* !CONFIG_MMU */ -- 2.34.1