diff options
Diffstat (limited to 'fs/coda/file.c')
| -rw-r--r-- | fs/coda/file.c | 183 |
1 files changed, 152 insertions, 31 deletions
diff --git a/fs/coda/file.c b/fs/coda/file.c index 1cbc1f2298ee..a390b5d21196 100644 --- a/fs/coda/file.c +++ b/fs/coda/file.c @@ -8,11 +8,13 @@ * to the Coda project. Contact Peter Braam <coda@cs.cmu.edu>. */ +#include <linux/refcount.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/time.h> #include <linux/file.h> #include <linux/fs.h> +#include <linux/pagemap.h> #include <linux/stat.h> #include <linux/cred.h> #include <linux/errno.h> @@ -20,22 +22,44 @@ #include <linux/string.h> #include <linux/slab.h> #include <linux/uaccess.h> +#include <linux/uio.h> +#include <linux/splice.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 { + refcount_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; + + 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; - BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC); + ret = vfs_iter_read(cfi->cfi_container, to, &iocb->ki_pos, 0); - return 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 @@ -43,41 +67,117 @@ 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); coda_inode->i_size = file_inode(host_file)->i_size; coda_inode->i_blocks = (coda_inode->i_size + 511) >> 9; - coda_inode->i_mtime = coda_inode->i_ctime = current_time(coda_inode); + inode_set_mtime_to_ts(coda_inode, inode_set_ctime_current(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 ssize_t +coda_file_splice_read(struct file *coda_file, loff_t *ppos, + struct pipe_inode_info *pipe, + size_t len, unsigned int flags) +{ + struct inode *coda_inode = file_inode(coda_file); + struct coda_file_info *cfi = coda_ftoc(coda_file); + struct file *in = cfi->cfi_container; + loff_t ki_pos = *ppos; + ssize_t ret; + + ret = venus_access_intent(coda_inode->i_sb, coda_i2f(coda_inode), + &cfi->cfi_access_intent, + len, ki_pos, CODA_ACCESS_TYPE_READ); + if (ret) + goto finish_read; + + ret = vfs_splice_read(in, ppos, pipe, len, flags); + +finish_read: + venus_access_intent(coda_inode->i_sb, coda_i2f(coda_inode), + &cfi->cfi_access_intent, + len, ki_pos, CODA_ACCESS_TYPE_READ_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); + + refcount_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 (refcount_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) + if (!can_mmap_file(host_file)) 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 +189,7 @@ 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 +198,29 @@ 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 = vfs_mmap(vma->vm_file, vma); + + if (ret) { + /* if vfs_mmap fails, our caller will put host_file so we + * should drop the reference to the coda_file that we got. + */ + fput(coda_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; + refcount_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 +250,8 @@ 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; @@ -140,12 +265,10 @@ int coda_release(struct inode *coda_inode, struct file *coda_file) struct coda_file_info *cfi; struct coda_inode_info *cii; 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), + venus_close(coda_inode->i_sb, coda_i2f(coda_inode), coda_flags, coda_file->f_cred->fsuid); host_inode = file_inode(cfi->cfi_container); @@ -185,8 +308,7 @@ 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); @@ -205,6 +327,5 @@ const struct file_operations coda_file_operations = { .open = coda_open, .release = coda_release, .fsync = coda_fsync, - .splice_read = generic_file_splice_read, + .splice_read = coda_file_splice_read, }; - |
