1 files changed, 123 insertions, 9 deletions

diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index b701d0207edf..c1e8eb984da8 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -13,6 +13,7 @@
 #include <linux/binfmts.h>
 #include <linux/sched/coredump.h>
 #include <linux/sched/task.h>
+#include <linux/mm.h>
 
 struct ctl_table_header;
 struct mempolicy;
@@ -43,7 +44,6 @@ struct proc_dir_entry {
 		const struct proc_ops *proc_ops;
 		const struct file_operations *proc_dir_ops;
 	};
-	const struct dentry_operations *proc_dops;
 	union {
 		const struct seq_operations *seq_ops;
 		int (*single_show)(struct seq_file *, void *);
@@ -84,6 +84,25 @@ static inline void pde_make_permanent(struct proc_dir_entry *pde)
 	pde->flags |= PROC_ENTRY_PERMANENT;
 }
 
+static inline bool pde_has_proc_read_iter(const struct proc_dir_entry *pde)
+{
+	return pde->flags & PROC_ENTRY_proc_read_iter;
+}
+
+static inline bool pde_has_proc_compat_ioctl(const struct proc_dir_entry *pde)
+{
+#ifdef CONFIG_COMPAT
+	return pde->flags & PROC_ENTRY_proc_compat_ioctl;
+#else
+	return false;
+#endif
+}
+
+static inline bool pde_has_proc_lseek(const struct proc_dir_entry *pde)
+{
+	return pde->flags & PROC_ENTRY_proc_lseek;
+}
+
 extern struct kmem_cache *proc_dir_entry_cache;
 void pde_free(struct proc_dir_entry *pde);
 
@@ -92,7 +111,7 @@ union proc_op {
 	int (*proc_show)(struct seq_file *m,
 		struct pid_namespace *ns, struct pid *pid,
 		struct task_struct *task);
-	const char *lsm;
+	int lsmid;
 };
 
 struct proc_inode {
@@ -101,7 +120,7 @@ struct proc_inode {
 	union proc_op op;
 	struct proc_dir_entry *pde;
 	struct ctl_table_header *sysctl;
-	struct ctl_table *sysctl_entry;
+	const struct ctl_table *sysctl_entry;
 	struct hlist_node sibling_inodes;
 	const struct proc_ns_operations *ns_ops;
 	struct inode vfs_inode;
@@ -142,6 +161,80 @@ unsigned name_to_int(const struct qstr *qstr);
 /* Worst case buffer size needed for holding an integer. */
 #define PROC_NUMBUF 13
 
+#ifdef CONFIG_PAGE_MAPCOUNT
+/**
+ * folio_precise_page_mapcount() - Number of mappings of this folio page.
+ * @folio: The folio.
+ * @page: The page.
+ *
+ * The number of present user page table entries that reference this page
+ * as tracked via the RMAP: either referenced directly (PTE) or as part of
+ * a larger area that covers this page (e.g., PMD).
+ *
+ * Use this function only for the calculation of existing statistics
+ * (USS, PSS, mapcount_max) and for debugging purposes (/proc/kpagecount).
+ *
+ * Do not add new users.
+ *
+ * Returns: The number of mappings of this folio page. 0 for
+ * folios that are not mapped to user space or are not tracked via the RMAP
+ * (e.g., shared zeropage).
+ */
+static inline int folio_precise_page_mapcount(struct folio *folio,
+		struct page *page)
+{
+	int mapcount = atomic_read(&page->_mapcount) + 1;
+
+	if (page_mapcount_is_type(mapcount))
+		mapcount = 0;
+	if (folio_test_large(folio))
+		mapcount += folio_entire_mapcount(folio);
+
+	return mapcount;
+}
+#else /* !CONFIG_PAGE_MAPCOUNT */
+static inline int folio_precise_page_mapcount(struct folio *folio,
+		struct page *page)
+{
+	BUILD_BUG();
+}
+#endif /* CONFIG_PAGE_MAPCOUNT */
+
+/**
+ * folio_average_page_mapcount() - Average number of mappings per page in this
+ *				   folio
+ * @folio: The folio.
+ *
+ * The average number of user page table entries that reference each page in
+ * this folio as tracked via the RMAP: either referenced directly (PTE) or
+ * as part of a larger area that covers this page (e.g., PMD).
+ *
+ * The average is calculated by rounding to the nearest integer; however,
+ * to avoid duplicated code in current callers, the average is at least
+ * 1 if any page of the folio is mapped.
+ *
+ * Returns: The average number of mappings per page in this folio.
+ */
+static inline int folio_average_page_mapcount(struct folio *folio)
+{
+	int mapcount, entire_mapcount, avg;
+
+	if (!folio_test_large(folio))
+		return atomic_read(&folio->_mapcount) + 1;
+
+	mapcount = folio_large_mapcount(folio);
+	if (unlikely(mapcount <= 0))
+		return 0;
+	entire_mapcount = folio_entire_mapcount(folio);
+	if (mapcount <= entire_mapcount)
+		return entire_mapcount;
+	mapcount -= entire_mapcount;
+
+	/* Round to closest integer ... */
+	avg = ((unsigned int)mapcount + folio_large_nr_pages(folio) / 2) >> folio_large_order(folio);
+	/* ... but return at least 1. */
+	return max_t(int, avg + entire_mapcount, 1);
+}
 /*
  * array.c
  */
@@ -162,9 +255,9 @@ extern int proc_pid_statm(struct seq_file *, struct pid_namespace *,
  * base.c
  */
 extern const struct dentry_operations pid_dentry_operations;
-extern int pid_getattr(struct user_namespace *, const struct path *,
+extern int pid_getattr(struct mnt_idmap *, const struct path *,
 		       struct kstat *, u32, unsigned int);
-extern int proc_setattr(struct user_namespace *, struct dentry *,
+extern int proc_setattr(struct mnt_idmap *, struct dentry *,
 			struct iattr *);
 extern void proc_pid_evict_inode(struct proc_inode *);
 extern struct inode *proc_pid_make_inode(struct super_block *, struct task_struct *, umode_t);
@@ -280,18 +373,27 @@ static inline void proc_tty_init(void) {}
 extern struct proc_dir_entry proc_root;
 
 extern void proc_self_init(void);
+extern unsigned self_inum, thread_self_inum;
 
 /*
  * task_[no]mmu.c
  */
 struct mem_size_stats;
+
+struct proc_maps_locking_ctx {
+	struct mm_struct *mm;
+#ifdef CONFIG_PER_VMA_LOCK
+	bool mmap_locked;
+	struct vm_area_struct *locked_vma;
+#endif
+};
+
 struct proc_maps_private {
 	struct inode *inode;
 	struct task_struct *task;
-	struct mm_struct *mm;
-#ifdef CONFIG_MMU
 	struct vma_iterator iter;
-#endif
+	loff_t last_pos;
+	struct proc_maps_locking_ctx lock_ctx;
 #ifdef CONFIG_NUMA
 	struct mempolicy *task_mempolicy;
 #endif
@@ -316,5 +418,17 @@ extern const struct dentry_operations proc_net_dentry_ops;
 static inline void pde_force_lookup(struct proc_dir_entry *pde)
 {
 	/* /proc/net/ entries can be changed under us by setns(CLONE_NEWNET) */
-	pde->proc_dops = &proc_net_dentry_ops;
+	pde->flags |= PROC_ENTRY_FORCE_LOOKUP;
+}
+
+/*
+ * Add a new procfs dentry that can't serve as a mountpoint. That should
+ * encompass anything that is ephemeral and can just disappear while the
+ * process is still around.
+ */
+static inline struct dentry *proc_splice_unmountable(struct inode *inode,
+		struct dentry *dentry, const struct dentry_operations *d_ops)
+{
+	dont_mount(dentry);
+	return d_splice_alias_ops(inode, dentry, d_ops);
 }