1 files changed, 119 insertions, 24 deletions

diff --git a/fs/coda/file.c b/fs/coda/file.c
index 1cbc1f2298ee..128d63df5bfb 100644
--- a/fs/coda/file.c
+++ b/fs/coda/file.c
@@ -20,22 +20,43 @@
 #include <linux/string.h>
 #include <linux/slab.h>
 #include <linux/uaccess.h>
+#include <linux/uio.h>
 
 #include <linux/coda.h>
-#include <linux/coda_psdev.h>
-
+#include "coda_psdev.h"
 #include "coda_linux.h"
 #include "coda_int.h"
 
+struct coda_vm_ops {
+        atomic_t refcnt;
+        struct file *coda_file;
+        const struct vm_operations_struct *host_vm_ops;
+        struct vm_operations_struct vm_ops;
+};
+
 static ssize_t
 coda_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
 {
         struct file *coda_file = iocb->ki_filp;
-        struct coda_file_info *cfi = CODA_FTOC(coda_file);
+        struct inode *coda_inode = file_inode(coda_file);
+        struct coda_file_info *cfi = coda_ftoc(coda_file);
+        loff_t ki_pos = iocb->ki_pos;
+        size_t count = iov_iter_count(to);
+        ssize_t ret;
 
-        BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
+        ret = venus_access_intent(coda_inode->i_sb, coda_i2f(coda_inode),
+                                  &cfi->cfi_access_intent,
+                                  count, ki_pos, CODA_ACCESS_TYPE_READ);
+        if (ret)
+                goto finish_read;
 
-        return vfs_iter_read(cfi->cfi_container, to, &iocb->ki_pos, 0);
+        ret = vfs_iter_read(cfi->cfi_container, to, &iocb->ki_pos, 0);
+
+finish_read:
+        venus_access_intent(coda_inode->i_sb, coda_i2f(coda_inode),
+                            &cfi->cfi_access_intent,
+                            count, ki_pos, CODA_ACCESS_TYPE_READ_FINISH);
+        return ret;
 }
 
 static ssize_t
@@ -43,13 +64,18 @@ coda_file_write_iter(struct kiocb *iocb, struct iov_iter *to)
 {
         struct file *coda_file = iocb->ki_filp;
         struct inode *coda_inode = file_inode(coda_file);
-        struct coda_file_info *cfi = CODA_FTOC(coda_file);
-        struct file *host_file;
+        struct coda_file_info *cfi = coda_ftoc(coda_file);
+        struct file *host_file = cfi->cfi_container;
+        loff_t ki_pos = iocb->ki_pos;
+        size_t count = iov_iter_count(to);
         ssize_t ret;
 
-        BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
+        ret = venus_access_intent(coda_inode->i_sb, coda_i2f(coda_inode),
+                                  &cfi->cfi_access_intent,
+                                  count, ki_pos, CODA_ACCESS_TYPE_WRITE);
+        if (ret)
+                goto finish_write;
 
-        host_file = cfi->cfi_container;
         file_start_write(host_file);
         inode_lock(coda_inode);
         ret = vfs_iter_write(cfi->cfi_container, to, &iocb->ki_pos, 0);
@@ -58,26 +84,73 @@ coda_file_write_iter(struct kiocb *iocb, struct iov_iter *to)
         coda_inode->i_mtime = coda_inode->i_ctime = current_time(coda_inode);
         inode_unlock(coda_inode);
         file_end_write(host_file);
+
+finish_write:
+        venus_access_intent(coda_inode->i_sb, coda_i2f(coda_inode),
+                            &cfi->cfi_access_intent,
+                            count, ki_pos, CODA_ACCESS_TYPE_WRITE_FINISH);
         return ret;
 }
 
+static void
+coda_vm_open(struct vm_area_struct *vma)
+{
+        struct coda_vm_ops *cvm_ops =
+                container_of(vma->vm_ops, struct coda_vm_ops, vm_ops);
+
+        atomic_inc(&cvm_ops->refcnt);
+
+        if (cvm_ops->host_vm_ops && cvm_ops->host_vm_ops->open)
+                cvm_ops->host_vm_ops->open(vma);
+}
+
+static void
+coda_vm_close(struct vm_area_struct *vma)
+{
+        struct coda_vm_ops *cvm_ops =
+                container_of(vma->vm_ops, struct coda_vm_ops, vm_ops);
+
+        if (cvm_ops->host_vm_ops && cvm_ops->host_vm_ops->close)
+                cvm_ops->host_vm_ops->close(vma);
+
+        if (atomic_dec_and_test(&cvm_ops->refcnt)) {
+                vma->vm_ops = cvm_ops->host_vm_ops;
+                fput(cvm_ops->coda_file);
+                kfree(cvm_ops);
+        }
+}
+
 static int
 coda_file_mmap(struct file *coda_file, struct vm_area_struct *vma)
 {
-        struct coda_file_info *cfi;
+        struct inode *coda_inode = file_inode(coda_file);
+        struct coda_file_info *cfi = coda_ftoc(coda_file);
+        struct file *host_file = cfi->cfi_container;
+        struct inode *host_inode = file_inode(host_file);
         struct coda_inode_info *cii;
-        struct file *host_file;
-        struct inode *coda_inode, *host_inode;
-
-        cfi = CODA_FTOC(coda_file);
-        BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
-        host_file = cfi->cfi_container;
+        struct coda_vm_ops *cvm_ops;
+        loff_t ppos;
+        size_t count;
+        int ret;
 
         if (!host_file->f_op->mmap)
                 return -ENODEV;
 
-        coda_inode = file_inode(coda_file);
-        host_inode = file_inode(host_file);
+        if (WARN_ON(coda_file != vma->vm_file))
+                return -EIO;
+
+        count = vma->vm_end - vma->vm_start;
+        ppos = vma->vm_pgoff * PAGE_SIZE;
+
+        ret = venus_access_intent(coda_inode->i_sb, coda_i2f(coda_inode),
+                                  &cfi->cfi_access_intent,
+                                  count, ppos, CODA_ACCESS_TYPE_MMAP);
+        if (ret)
+                return ret;
+
+        cvm_ops = kmalloc(sizeof(struct coda_vm_ops), GFP_KERNEL);
+        if (!cvm_ops)
+                return -ENOMEM;
 
         cii = ITOC(coda_inode);
         spin_lock(&cii->c_lock);
@@ -89,6 +162,7 @@ coda_file_mmap(struct file *coda_file, struct vm_area_struct *vma)
          * the container file on us! */
         else if (coda_inode->i_mapping != host_inode->i_mapping) {
                 spin_unlock(&cii->c_lock);
+                kfree(cvm_ops);
                 return -EBUSY;
         }
 
@@ -97,7 +171,29 @@ coda_file_mmap(struct file *coda_file, struct vm_area_struct *vma)
         cfi->cfi_mapcount++;
         spin_unlock(&cii->c_lock);
 
-        return call_mmap(host_file, vma);
+        vma->vm_file = get_file(host_file);
+        ret = call_mmap(vma->vm_file, vma);
+
+        if (ret) {
+                /* if call_mmap fails, our caller will put coda_file so we
+                 * should drop the reference to the host_file that we got.
+                 */
+                fput(host_file);
+                kfree(cvm_ops);
+        } else {
+                /* here we add redirects for the open/close vm_operations */
+                cvm_ops->host_vm_ops = vma->vm_ops;
+                if (vma->vm_ops)
+                        cvm_ops->vm_ops = *vma->vm_ops;
+
+                cvm_ops->vm_ops.open = coda_vm_open;
+                cvm_ops->vm_ops.close = coda_vm_close;
+                cvm_ops->coda_file = coda_file;
+                atomic_set(&cvm_ops->refcnt, 1);
+
+                vma->vm_ops = &cvm_ops->vm_ops;
+        }
+        return ret;
 }
 
 int coda_open(struct inode *coda_inode, struct file *coda_file)
@@ -127,6 +223,8 @@ int coda_open(struct inode *coda_inode, struct file *coda_file)
         cfi->cfi_magic = CODA_MAGIC;
         cfi->cfi_mapcount = 0;
         cfi->cfi_container = host_file;
+        /* assume access intents are supported unless we hear otherwise */
+        cfi->cfi_access_intent = true;
 
         BUG_ON(coda_file->private_data != NULL);
         coda_file->private_data = cfi;
@@ -142,8 +240,7 @@ int coda_release(struct inode *coda_inode, struct file *coda_file)
         struct inode *host_inode;
         int err;
 
-        cfi = CODA_FTOC(coda_file);
-        BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
+        cfi = coda_ftoc(coda_file);
 
         err = venus_close(coda_inode->i_sb, coda_i2f(coda_inode),
                           coda_flags, coda_file->f_cred->fsuid);
@@ -185,8 +282,7 @@ int coda_fsync(struct file *coda_file, loff_t start, loff_t end, int datasync)
                 return err;
         inode_lock(coda_inode);
 
-        cfi = CODA_FTOC(coda_file);
-        BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
+        cfi = coda_ftoc(coda_file);
         host_file = cfi->cfi_container;
 
         err = vfs_fsync(host_file, datasync);
@@ -207,4 +303,3 @@ const struct file_operations coda_file_operations = {
         .fsync          = coda_fsync,
         .splice_read    = generic_file_splice_read,
 };
-