Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/drzeus/mmc
[powerpc.git] / fs / cifs / file.c
index b1807fd..dd26e27 100644 (file)
@@ -130,7 +130,9 @@ static inline int cifs_open_inode_helper(struct inode *inode, struct file *file,
                if (file->f_path.dentry->d_inode->i_mapping) {
                /* BB no need to lock inode until after invalidate
                   since namei code should already have it locked? */
-                       filemap_write_and_wait(file->f_path.dentry->d_inode->i_mapping);
+                       rc = filemap_write_and_wait(file->f_path.dentry->d_inode->i_mapping);
+                       if (rc != 0)
+                               CIFS_I(file->f_path.dentry->d_inode)->write_behind_rc = rc;
                }
                cFYI(1, ("invalidating remote inode since open detected it "
                         "changed"));
@@ -425,7 +427,9 @@ reopen_error_exit:
                pCifsInode = CIFS_I(inode);
                if (pCifsInode) {
                        if (can_flush) {
-                               filemap_write_and_wait(inode->i_mapping);
+                               rc = filemap_write_and_wait(inode->i_mapping);
+                               if (rc != 0)
+                                       CIFS_I(inode)->write_behind_rc = rc;
                        /* temporarily disable caching while we
                           go to server to get inode info */
                                pCifsInode->clientCanCacheAll = FALSE;
@@ -545,6 +549,7 @@ int cifs_close(struct inode *inode, struct file *file)
        } else
                rc = -EBADF;
 
+       read_lock(&GlobalSMBSeslock);
        if (list_empty(&(CIFS_I(inode)->openFileList))) {
                cFYI(1, ("closing last open instance for inode %p", inode));
                /* if the file is not open we do not know if we can cache info
@@ -552,6 +557,7 @@ int cifs_close(struct inode *inode, struct file *file)
                CIFS_I(inode)->clientCanCacheRead = FALSE;
                CIFS_I(inode)->clientCanCacheAll  = FALSE;
        }
+       read_unlock(&GlobalSMBSeslock);
        if ((rc == 0) && CIFS_I(inode)->write_behind_rc)
                rc = CIFS_I(inode)->write_behind_rc;
        FreeXid(xid);
@@ -833,9 +839,9 @@ ssize_t cifs_user_write(struct file *file, const char __user *write_data,
        xid = GetXid();
 
        if (*poffset > file->f_path.dentry->d_inode->i_size)
-               long_op = 2; /* writes past end of file can take a long time */
+               long_op = CIFS_VLONG_OP; /* writes past EOF take long time */
        else
-               long_op = 1;
+               long_op = CIFS_LONG_OP;
 
        for (total_written = 0; write_size > total_written;
             total_written += bytes_written) {
@@ -882,7 +888,7 @@ ssize_t cifs_user_write(struct file *file, const char __user *write_data,
                        }
                } else
                        *poffset += bytes_written;
-               long_op = FALSE; /* subsequent writes fast -
+               long_op = CIFS_STD_OP; /* subsequent writes fast -
                                    15 seconds is plenty */
        }
 
@@ -932,9 +938,9 @@ static ssize_t cifs_write(struct file *file, const char *write_data,
        xid = GetXid();
 
        if (*poffset > file->f_path.dentry->d_inode->i_size)
-               long_op = 2; /* writes past end of file can take a long time */
+               long_op = CIFS_VLONG_OP; /* writes past EOF can be slow */
        else
-               long_op = 1;
+               long_op = CIFS_LONG_OP;
 
        for (total_written = 0; write_size > total_written;
             total_written += bytes_written) {
@@ -1000,7 +1006,7 @@ static ssize_t cifs_write(struct file *file, const char *write_data,
                        }
                } else
                        *poffset += bytes_written;
-               long_op = FALSE; /* subsequent writes fast -
+               long_op = CIFS_STD_OP; /* subsequent writes fast -
                                    15 seconds is plenty */
        }
 
@@ -1024,6 +1030,37 @@ static ssize_t cifs_write(struct file *file, const char *write_data,
        return total_written;
 }
 
+#ifdef CONFIG_CIFS_EXPERIMENTAL
+struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode)
+{
+       struct cifsFileInfo *open_file = NULL;
+
+       read_lock(&GlobalSMBSeslock);
+       /* we could simply get the first_list_entry since write-only entries
+          are always at the end of the list but since the first entry might
+          have a close pending, we go through the whole list */
+       list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
+               if (open_file->closePend)
+                       continue;
+               if (open_file->pfile && ((open_file->pfile->f_flags & O_RDWR) ||
+                   (open_file->pfile->f_flags & O_RDONLY))) {
+                       if (!open_file->invalidHandle) {
+                               /* found a good file */
+                               /* lock it so it will not be closed on us */
+                               atomic_inc(&open_file->wrtPending);
+                               read_unlock(&GlobalSMBSeslock);
+                               return open_file;
+                       } /* else might as well continue, and look for
+                            another, or simply have the caller reopen it
+                            again rather than trying to fix this handle */
+               } else /* write only file */
+                       break; /* write only files are last so must be done */
+       }
+       read_unlock(&GlobalSMBSeslock);
+       return NULL;
+}
+#endif
+
 struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode)
 {
        struct cifsFileInfo *open_file;
@@ -1040,6 +1077,7 @@ struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode)
        }
 
        read_lock(&GlobalSMBSeslock);
+refind_writable:
        list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
                if (open_file->closePend)
                        continue;
@@ -1047,26 +1085,49 @@ struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode)
                    ((open_file->pfile->f_flags & O_RDWR) ||
                     (open_file->pfile->f_flags & O_WRONLY))) {
                        atomic_inc(&open_file->wrtPending);
+
+                       if (!open_file->invalidHandle) {
+                               /* found a good writable file */
+                               read_unlock(&GlobalSMBSeslock);
+                               return open_file;
+                       }
+
                        read_unlock(&GlobalSMBSeslock);
-                       if (open_file->invalidHandle) {
-                               rc = cifs_reopen_file(open_file->pfile, FALSE);
-                               /* if it fails, try another handle - might be */
-                               /* dangerous to hold up writepages with retry */
-                               if (rc) {
-                                       cFYI(1, ("wp failed on reopen file"));
+                       /* Had to unlock since following call can block */
+                       rc = cifs_reopen_file(open_file->pfile, FALSE);
+                       if (!rc) {
+                               if (!open_file->closePend)
+                                       return open_file;
+                               else { /* start over in case this was deleted */
+                                      /* since the list could be modified */
                                        read_lock(&GlobalSMBSeslock);
-                                       /* can not use this handle, no write
-                                       pending on this one after all */
                                        atomic_dec(&open_file->wrtPending);
-                                       continue;
+                                       goto refind_writable;
                                }
                        }
-                       if (open_file->closePend) {
-                               read_lock(&GlobalSMBSeslock);
-                               atomic_dec(&open_file->wrtPending);
-                               continue;
-                       }
-                       return open_file;
+
+                       /* if it fails, try another handle if possible -
+                       (we can not do this if closePending since
+                       loop could be modified - in which case we
+                       have to start at the beginning of the list
+                       again. Note that it would be bad
+                       to hold up writepages here (rather than
+                       in caller) with continuous retries */
+                       cFYI(1, ("wp failed on reopen file"));
+                       read_lock(&GlobalSMBSeslock);
+                       /* can not use this handle, no write
+                          pending on this one after all */
+                       atomic_dec(&open_file->wrtPending);
+
+                       if (open_file->closePend) /* list could have changed */
+                               goto refind_writable;
+                       /* else we simply continue to the next entry. Thus
+                          we do not loop on reopen errors.  If we
+                          can not reopen the file, for example if we
+                          reconnected to a server with another client
+                          racing to delete or lock the file we would not
+                          make progress if we restarted before the beginning
+                          of the loop here. */
                }
        }
        read_unlock(&GlobalSMBSeslock);
@@ -1303,14 +1364,17 @@ retry:
                                                   open_file->netfid,
                                                   bytes_to_write, offset,
                                                   &bytes_written, iov, n_iov,
-                                                  1);
+                                                  CIFS_LONG_OP);
                                atomic_dec(&open_file->wrtPending);
                                if (rc || bytes_written < bytes_to_write) {
                                        cERROR(1, ("Write2 ret %d, wrote %d",
                                                  rc, bytes_written));
                                        /* BB what if continued retry is
                                           requested via mount flags? */
-                                       set_bit(AS_EIO, &mapping->flags);
+                                       if (rc == -ENOSPC)
+                                               set_bit(AS_ENOSPC, &mapping->flags);
+                                       else
+                                               set_bit(AS_EIO, &mapping->flags);
                                } else {
                                        cifs_stats_bytes_written(cifs_sb->tcon,
                                                                 bytes_written);
@@ -1442,9 +1506,11 @@ int cifs_fsync(struct file *file, struct dentry *dentry, int datasync)
        cFYI(1, ("Sync file - name: %s datasync: 0x%x",
                dentry->d_name.name, datasync));
 
-       rc = filemap_fdatawrite(inode->i_mapping);
-       if (rc == 0)
+       rc = filemap_write_and_wait(inode->i_mapping);
+       if (rc == 0) {
+               rc = CIFS_I(inode)->write_behind_rc;
                CIFS_I(inode)->write_behind_rc = 0;
+       }
        FreeXid(xid);
        return rc;
 }
@@ -1496,8 +1562,11 @@ int cifs_flush(struct file *file, fl_owner_t id)
           filemapfdatawrite appears easier for the time being */
 
        rc = filemap_fdatawrite(inode->i_mapping);
-       if (!rc) /* reset wb rc if we were able to write out dirty pages */
+       /* reset wb rc if we were able to write out dirty pages */
+       if (!rc) {
+               rc = CIFS_I(inode)->write_behind_rc;
                CIFS_I(inode)->write_behind_rc = 0;
+       }
 
        cFYI(1, ("Flush inode %p file %p rc %d", inode, file, rc));
 
@@ -1729,7 +1798,7 @@ static int cifs_readpages(struct file *file, struct address_space *mapping,
        struct page *page;
        struct cifs_sb_info *cifs_sb;
        struct cifsTconInfo *pTcon;
-       int bytes_read = 0;
+       unsigned int bytes_read = 0;
        unsigned int read_size, i;
        char *smb_read_data = NULL;
        struct smb_com_read_rsp *pSMBr;
@@ -1823,7 +1892,7 @@ static int cifs_readpages(struct file *file, struct address_space *mapping,
 
                        i +=  bytes_read >> PAGE_CACHE_SHIFT;
                        cifs_stats_bytes_read(pTcon, bytes_read);
-                       if ((int)(bytes_read & PAGE_CACHE_MASK) != bytes_read) {
+                       if ((bytes_read & PAGE_CACHE_MASK) != bytes_read) {
                                i++; /* account for partial page */
 
                                /* server copy of file can have smaller size