aufs5.x-rcN mmap patch

Origin: https://github.com/sfjro/aufs5-standalone/tree/3d29dbdc3205e8958c3d78237dff8703014d34ea
Bug-Debian: https://bugs.debian.org/541828

Patch headers added by debian/bin/genpatch-aufs

SPDX-License-Identifier: GPL-2.0
aufs5.x-rcN mmap patch

Gbp-Pq: Topic features/all/aufs5
Gbp-Pq: Name aufs5-mmap.patch

diff --git a/fs/proc/base.c b/fs/proc/base.c
index ebea9501afb84cd8969d2a4a4a25361a91e353c3..dc7edc5f7267d3aea41c9f97d8b7447453cfd848 100644 (file)
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2037,7 +2037,7 @@ 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 14c2badb8fd93bc1d2963f29807758337b39e818..65afe5287e43e27574c76bc0cf1d3bca9da9752f 100644 (file)
--- a/fs/proc/nommu.c
+++ b/fs/proc/nommu.c
@@ -41,7 +41,10 @@ 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 9442631fd4afcb16e3a09d6a661ebdc630fcbe87..1fa8a5fcdeeecedc816e58493633761d3fa71658 100644 (file)
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -309,7 +309,10 @@ 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;
@@ -1819,7 +1822,7 @@ 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 7907e6419e5726702b0cd8eac2d57a5bd48306f8..d17209cf52bc356c2093e7ed18e7c023da4284dd 100644 (file)
--- a/fs/proc/task_nommu.c
+++ b/fs/proc/task_nommu.c
@@ -155,7 +155,10 @@ 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 70f4278bb193c329f5119871dace185cad5d18b0..71a9e63db17504cbabaa44549fb665470100b099 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1495,6 +1495,28 @@ static inline void unmap_shared_mapping_range(struct address_space *mapping,
        unmap_mapping_range(mapping, holebegin, holelen, 0);
 }
 
+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 */
+
 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 270aa8fd2800b4234297fa7c27577705f8c24395..33848c2165e21b5a1f31d2e4311189a0c2ac5221 100644 (file)
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -267,6 +267,7 @@ 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 */
+       struct file     *vm_prfile;     /* the virtual backing file or NULL */
 
        int             vm_usage;       /* region usage count (access under nommu_region_sem) */
        bool            vm_icache_flushed : 1; /* true if the icache has been flushed for
@@ -341,6 +342,7 @@ 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). */
+       struct file *vm_prfile;         /* shadow of vm_file */
        void * vm_private_data;         /* was vm_pte (shared mem) */
 
 #ifdef CONFIG_SWAP

diff --git a/kernel/fork.c b/kernel/fork.c
index 1d964d63b0946facbdac1f8dafe1089b721681c4..51e0b248b8ffa6f29f30182bc0321f2e7783c7bb 100644 (file)
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -565,7 +565,7 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
                        struct inode *inode = file_inode(file);
                        struct address_space *mapping = file->f_mapping;
 
-                       get_file(file);
+                       vma_get_file(tmp);
                        if (tmp->vm_flags & VM_DENYWRITE)
                                atomic_dec(&inode->i_writecount);
                        i_mmap_lock_write(mapping);

diff --git a/mm/Makefile b/mm/Makefile
index 1937cc2518836dde1e2555345ba33e7a413509c4..778c1e399903eb0e169cff71d93ad74860e9febb 100644 (file)
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -42,7 +42,7 @@ obj-y                 := filemap.o mempool.o oom_kill.o fadvise.o \
                           mm_init.o mmu_context.o percpu.o slab_common.o \
                           compaction.o vmacache.o \
                           interval_tree.o list_lru.o workingset.o \
-                          debug.o gup.o $(mmu-y)
+                          prfile.o debug.o gup.o $(mmu-y)
 
 # Give 'page_alloc' its own module-parameter namespace
 page-alloc-y := page_alloc.o

diff --git a/mm/filemap.c b/mm/filemap.c
index bf6aa30be58dca822906d55001e563fa0b4d2e8a..32ca075c0c8b183a084992c1f1e2abbde29d6e46 100644 (file)
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2675,7 +2675,7 @@ vm_fault_t filemap_page_mkwrite(struct vm_fault *vmf)
        vm_fault_t ret = VM_FAULT_LOCKED;
 
        sb_start_pagefault(inode->i_sb);
-       file_update_time(vmf->vma->vm_file);
+       vma_file_update_time(vmf->vma);
        lock_page(page);
        if (page->mapping != inode->i_mapping) {
                unlock_page(page);

diff --git a/mm/mmap.c b/mm/mmap.c
index cb2c79a3e914b3c88fa10f9f089cc41d187e6fed..ca06e9c65a9e9944a44068e13d8ef335cb1883b0 100644 (file)
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -176,7 +176,7 @@ static struct vm_area_struct *remove_vma(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);
        mpol_put(vma_policy(vma));
        vm_area_free(vma);
        return next;
@@ -907,7 +907,7 @@ again:
        if (remove_next) {
                if (file) {
                        uprobe_munmap(next, next->vm_start, next->vm_end);
-                       fput(file);
+                       vma_fput(vma);
                }
                if (next->anon_vma)
                        anon_vma_merge(vma, next);
@@ -1833,8 +1833,8 @@ out:
        return addr;
 
 unmap_and_free_vma:
+       vma_fput(vma);
        vma->vm_file = NULL;
-       fput(file);
 
        /* Undo any partial mapping done by a device driver. */
        unmap_region(mm, vma, prev, vma->vm_start, vma->vm_end);
@@ -2663,7 +2663,7 @@ int __split_vma(struct mm_struct *mm, 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);
@@ -2682,7 +2682,7 @@ int __split_vma(struct mm_struct *mm, struct vm_area_struct *vma,
        if (new->vm_ops && new->vm_ops->close)
                new->vm_ops->close(new);
        if (new->vm_file)
-               fput(new->vm_file);
+               vma_fput(new);
        unlink_anon_vmas(new);
  out_free_mpol:
        mpol_put(vma_policy(new));
@@ -2874,7 +2874,7 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
        struct vm_area_struct *vma;
        unsigned long populate = 0;
        unsigned long ret = -EINVAL;
-       struct file *file;
+       struct file *file, *prfile;
 
        pr_warn_once("%s (%d) uses deprecated remap_file_pages() syscall. See Documentation/vm/remap_file_pages.rst.\n",
                     current->comm, current->pid);
@@ -2949,10 +2949,27 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
                }
        }
 
-       file = get_file(vma->vm_file);
+       vma_get_file(vma);
+       file = vma->vm_file;
+       prfile = vma->vm_prfile;
        ret = do_mmap_pgoff(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 (new_vma != vma)
+                       get_file(prfile);
+       }
+       /*
+        * two fput()s instead of vma_fput(vma),
+        * coz vma may not be available anymore.
+        */
        fput(file);
+       if (prfile)
+               fput(prfile);
 out:
        up_write(&mm->mmap_sem);
        if (populate)
@@ -3243,7 +3260,7 @@ 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);
                vma_link(mm, new_vma, prev, rb_link, rb_parent);

diff --git a/mm/nommu.c b/mm/nommu.c
index 318df4e236c99003e81880e8619c111a3138dcdf..7f051e86ea1ddf8ace54f4b62b6e236ab27c555f 100644 (file)
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -567,7 +567,7 @@ 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 */
@@ -699,7 +699,7 @@ 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);
 }
@@ -1222,7 +1222,7 @@ 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;
@@ -1299,10 +1299,10 @@ error_just_free:
        up_write(&nommu_region_sem);
 error:
        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 (file)
index 0000000..024cdcf
--- /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) 2014-2019 Junjro R. Okajima
+ * Copyright (c) 2014 Ian Campbell
+ */
+
+#include <linux/mm.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+
+/* #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 */