kexec: define kexec_in_progress in !CONFIG_KEXEC case

[firefly-linux-kernel-4.4.55.git] / mm / shmem.c

diff --git a/mm/shmem.c b/mm/shmem.c
index cf2d0ca010bc52efd5ea86c7f6ba760a5c3ef286..4caf8ed24d6586e32ab910f28f945c01cef6373b 100644 (file)
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -31,7 +31,7 @@
 #include <linux/mm.h>
 #include <linux/export.h>
 #include <linux/swap.h>
-#include <linux/aio.h>
+#include <linux/uio.h>
 
 static struct vfsmount *shm_mnt;
 
@@ -544,7 +544,7 @@ EXPORT_SYMBOL_GPL(shmem_truncate_range);
 
 static int shmem_setattr(struct dentry *dentry, struct iattr *attr)
 {
-       struct inode *inode = dentry->d_inode;
+       struct inode *inode = d_inode(dentry);
        struct shmem_inode_info *info = SHMEM_I(inode);
        int error;
 
@@ -569,7 +569,7 @@ static int shmem_setattr(struct dentry *dentry, struct iattr *attr)
                        i_size_write(inode, newsize);
                        inode->i_ctime = inode->i_mtime = CURRENT_TIME;
                }
-               if (newsize < oldsize) {
+               if (newsize <= oldsize) {
                        loff_t holebegin = round_up(newsize, PAGE_SIZE);
                        unmap_mapping_range(inode->i_mapping, holebegin, 0, 1);
                        shmem_truncate_range(inode, newsize, (loff_t)-1);
@@ -2274,7 +2274,7 @@ static int shmem_create(struct inode *dir, struct dentry *dentry, umode_t mode,
  */
 static int shmem_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
 {
-       struct inode *inode = old_dentry->d_inode;
+       struct inode *inode = d_inode(old_dentry);
        int ret;
 
        /*
@@ -2298,7 +2298,7 @@ out:
 
 static int shmem_unlink(struct inode *dir, struct dentry *dentry)
 {
-       struct inode *inode = dentry->d_inode;
+       struct inode *inode = d_inode(dentry);
 
        if (inode->i_nlink > 1 && !S_ISDIR(inode->i_mode))
                shmem_free_inode(inode->i_sb);
@@ -2315,7 +2315,7 @@ static int shmem_rmdir(struct inode *dir, struct dentry *dentry)
        if (!simple_empty(dentry))
                return -ENOTEMPTY;
 
-       drop_nlink(dentry->d_inode);
+       drop_nlink(d_inode(dentry));
        drop_nlink(dir);
        return shmem_unlink(dir, dentry);
 }
@@ -2336,8 +2336,8 @@ static int shmem_exchange(struct inode *old_dir, struct dentry *old_dentry, stru
        }
        old_dir->i_ctime = old_dir->i_mtime =
        new_dir->i_ctime = new_dir->i_mtime =
-       old_dentry->d_inode->i_ctime =
-       new_dentry->d_inode->i_ctime = CURRENT_TIME;
+       d_inode(old_dentry)->i_ctime =
+       d_inode(new_dentry)->i_ctime = CURRENT_TIME;
 
        return 0;
 }
@@ -2376,7 +2376,7 @@ static int shmem_whiteout(struct inode *old_dir, struct dentry *old_dentry)
  */
 static int shmem_rename2(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, unsigned int flags)
 {
-       struct inode *inode = old_dentry->d_inode;
+       struct inode *inode = d_inode(old_dentry);
        int they_are_dirs = S_ISDIR(inode->i_mode);
 
        if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
@@ -2396,10 +2396,10 @@ static int shmem_rename2(struct inode *old_dir, struct dentry *old_dentry, struc
                        return error;
        }
 
-       if (new_dentry->d_inode) {
+       if (d_really_is_positive(new_dentry)) {
                (void) shmem_unlink(new_dir, new_dentry);
                if (they_are_dirs) {
-                       drop_nlink(new_dentry->d_inode);
+                       drop_nlink(d_inode(new_dentry));
                        drop_nlink(old_dir);
                }
        } else if (they_are_dirs) {
@@ -2451,6 +2451,7 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s
                        return -ENOMEM;
                }
                inode->i_op = &shmem_short_symlink_operations;
+               inode->i_link = info->symlink;
        } else {
                error = shmem_getpage(inode, 0, &page, SGP_WRITE, NULL);
                if (error) {
@@ -2474,30 +2475,23 @@ static int shmem_symlink(struct inode *dir, struct dentry *dentry, const char *s
        return 0;
 }
 
-static void *shmem_follow_short_symlink(struct dentry *dentry, struct nameidata *nd)
-{
-       nd_set_link(nd, SHMEM_I(dentry->d_inode)->symlink);
-       return NULL;
-}
-
-static void *shmem_follow_link(struct dentry *dentry, struct nameidata *nd)
+static const char *shmem_follow_link(struct dentry *dentry, void **cookie)
 {
        struct page *page = NULL;
-       int error = shmem_getpage(dentry->d_inode, 0, &page, SGP_READ, NULL);
-       nd_set_link(nd, error ? ERR_PTR(error) : kmap(page));
-       if (page)
-               unlock_page(page);
-       return page;
+       int error = shmem_getpage(d_inode(dentry), 0, &page, SGP_READ, NULL);
+       if (error)
+               return ERR_PTR(error);
+       unlock_page(page);
+       *cookie = page;
+       return kmap(page);
 }
 
-static void shmem_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie)
+static void shmem_put_link(struct inode *unused, void *cookie)
 {
-       if (!IS_ERR(nd_get_link(nd))) {
-               struct page *page = cookie;
-               kunmap(page);
-               mark_page_accessed(page);
-               page_cache_release(page);
-       }
+       struct page *page = cookie;
+       kunmap(page);
+       mark_page_accessed(page);
+       page_cache_release(page);
 }
 
 #ifdef CONFIG_TMPFS_XATTR
@@ -2574,7 +2568,7 @@ static int shmem_xattr_validate(const char *name)
 static ssize_t shmem_getxattr(struct dentry *dentry, const char *name,
                              void *buffer, size_t size)
 {
-       struct shmem_inode_info *info = SHMEM_I(dentry->d_inode);
+       struct shmem_inode_info *info = SHMEM_I(d_inode(dentry));
        int err;
 
        /*
@@ -2595,7 +2589,7 @@ static ssize_t shmem_getxattr(struct dentry *dentry, const char *name,
 static int shmem_setxattr(struct dentry *dentry, const char *name,
                          const void *value, size_t size, int flags)
 {
-       struct shmem_inode_info *info = SHMEM_I(dentry->d_inode);
+       struct shmem_inode_info *info = SHMEM_I(d_inode(dentry));
        int err;
 
        /*
@@ -2615,7 +2609,7 @@ static int shmem_setxattr(struct dentry *dentry, const char *name,
 
 static int shmem_removexattr(struct dentry *dentry, const char *name)
 {
-       struct shmem_inode_info *info = SHMEM_I(dentry->d_inode);
+       struct shmem_inode_info *info = SHMEM_I(d_inode(dentry));
        int err;
 
        /*
@@ -2635,14 +2629,14 @@ static int shmem_removexattr(struct dentry *dentry, const char *name)
 
 static ssize_t shmem_listxattr(struct dentry *dentry, char *buffer, size_t size)
 {
-       struct shmem_inode_info *info = SHMEM_I(dentry->d_inode);
+       struct shmem_inode_info *info = SHMEM_I(d_inode(dentry));
        return simple_xattr_list(&info->xattrs, buffer, size);
 }
 #endif /* CONFIG_TMPFS_XATTR */
 
 static const struct inode_operations shmem_short_symlink_operations = {
        .readlink       = generic_readlink,
-       .follow_link    = shmem_follow_short_symlink,
+       .follow_link    = simple_follow_link,
 #ifdef CONFIG_TMPFS_XATTR
        .setxattr       = shmem_setxattr,
        .getxattr       = shmem_getxattr,
@@ -3118,8 +3112,6 @@ static const struct file_operations shmem_file_operations = {
        .mmap           = shmem_mmap,
 #ifdef CONFIG_TMPFS
        .llseek         = shmem_file_llseek,
-       .read           = new_sync_read,
-       .write          = new_sync_write,
        .read_iter      = shmem_file_read_iter,
        .write_iter     = generic_file_write_iter,
        .fsync          = noop_fsync,
@@ -3403,7 +3395,13 @@ int shmem_zero_setup(struct vm_area_struct *vma)
        struct file *file;
        loff_t size = vma->vm_end - vma->vm_start;
 
-       file = shmem_file_setup("dev/zero", size, vma->vm_flags);
+       /*
+        * Cloning a new file under mmap_sem leads to a lock ordering conflict
+        * between XFS directory reading and selinux: since this file is only
+        * accessible to the user through its mapping, use S_PRIVATE flag to
+        * bypass file security, in the same way as shmem_kernel_file_setup().
+        */
+       file = __shmem_file_setup("dev/zero", size, vma->vm_flags, S_PRIVATE);
        if (IS_ERR(file))
                return PTR_ERR(file);