fuse: +max_pages

index e03ca14f40e9..f51100505c5b 100644
@@ -1648,7 +1648,7 @@ static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode,
 	unsigned int num;
 	unsigned int offset;
 	size_t total_len = 0;
-	int num_pages;
+	unsigned num_pages;
 
 	offset = outarg->offset & ~PAGE_MASK;
 	file_size = i_size_read(inode);

@@ -1660,7 +1660,7 @@ static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode,
 		num = file_size - outarg->offset;
 
 	num_pages = (num + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
-	num_pages = min(num_pages, FUSE_MAX_PAGES_PER_REQ);
+	num_pages = min(num_pages, fc->max_pages);
 
 	req = fuse_get_req(fc, num_pages);
 	if (IS_ERR(req))

171 lines not on this page · raw message

index 5256ad333b05..64fafe78759e 100644
@@ -29,7 +29,7 @@
 #include <linux/user_namespace.h>
 
 /** Max number of pages that can be used in a single read request */
-#define FUSE_MAX_PAGES_PER_REQ 32
+#define FUSE_DEFAULT_MAX_PAGES_PER_REQ 32
 
 /** Bias for fi->writectr, meaning new writepages must not be sent */
 #define FUSE_NOWRITE INT_MIN

@@ -476,6 +476,9 @@ struct fuse_conn {
 	/** Maximum write size */
 	unsigned max_write;
 
+	/** Maxmum number of pages that can be used in a single request */
+	unsigned max_pages;
+
 	/** Input queue */
 	struct fuse_iqueue iq;
 

index 061500c72608..19eed0297e83 100644
@@ -22,6 +22,7 @@
 #include <linux/exportfs.h>
 #include <linux/posix_acl.h>
 #include <linux/pid_namespace.h>
+#include <linux/pipe_fs_i.h>
 
 MODULE_AUTHOR("Miklos Szeredi <[email protected]>");
 MODULE_DESCRIPTION("Filesystem in Userspace");

@@ -71,6 +72,7 @@ struct fuse_mount_data {
 	unsigned default_permissions:1;
 	unsigned allow_other:1;
 	unsigned max_read;
+	unsigned max_pages;
 	unsigned blksize;
 };
 

@@ -450,6 +452,7 @@ enum {
 	OPT_DEFAULT_PERMISSIONS,
 	OPT_ALLOW_OTHER,
 	OPT_MAX_READ,
+	OPT_MAX_PAGES,
 	OPT_BLKSIZE,
 	OPT_ERR
 };

@@ -462,6 +465,7 @@ static const match_table_t tokens = {
 	{OPT_DEFAULT_PERMISSIONS,	"default_permissions"},
 	{OPT_ALLOW_OTHER,		"allow_other"},
 	{OPT_MAX_READ,			"max_read=%u"},
+	{OPT_MAX_PAGES,                 "max_pages=%u"},
 	{OPT_BLKSIZE,			"blksize=%u"},
 	{OPT_ERR,			NULL}
 };

@@ -543,6 +547,12 @@ static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev,
 			d->max_read = value;
 			break;
 
+		case OPT_MAX_PAGES:
+			if (match_int(&args[0], &value))
+				return 0;
+			d->max_pages = value;
+			break;
+
 		case OPT_BLKSIZE:
 			if (!is_bdev || match_int(&args[0], &value))
 				return 0;

@@ -574,6 +584,8 @@ static int fuse_show_options(struct seq_file *m, struct dentry *root)
 		seq_puts(m, ",allow_other");
 	if (fc->max_read != ~0)
 		seq_printf(m, ",max_read=%u", fc->max_read);
+	if (fc->max_pages != FUSE_DEFAULT_MAX_PAGES_PER_REQ)
+		seq_printf(m, ",max_pages=%u", fc->max_pages);
 	if (sb->s_bdev && sb->s_blocksize != FUSE_DEFAULT_BLKSIZE)
 		seq_printf(m, ",blksize=%lu", sb->s_blocksize);
 	return 0;

@@ -1135,6 +1147,9 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
 	fc->user_id = d.user_id;
 	fc->group_id = d.group_id;
 	fc->max_read = max_t(unsigned, 4096, d.max_read);
+	fc->max_pages = min_t(unsigned, pipe_max_size >> PAGE_SHIFT,
+			      max_t(unsigned, FUSE_DEFAULT_MAX_PAGES_PER_REQ,
+				    d.max_pages));
 
 	/* Used by get_root_inode() */
 	sb->s_fs_info = fc;

index 7b1954caf388..a1b208eb8393 100644
@@ -34,6 +34,7 @@
  * be set by root in /proc/sys/fs/pipe-max-size
  */
 unsigned int pipe_max_size = 1048576;
+EXPORT_SYMBOL(pipe_max_size);
 
 /* Maximum allocatable pages per user. Hard limit is unset by default, soft
  * matches default values.