litmus-rt.git - The LITMUS^RT kernel.

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author	Yongqiang Yang <xiaoqiangnk@gmail.com>	2011-04-10 22:06:07 -0400
committer	Theodore Ts'o <tytso@mit.edu>	2011-04-10 22:06:07 -0400
commit	be4f27d324e8ddd57cc0d4d604fe85ee0425cba9 (patch)
tree	e4262a9e1ade9095e1bf937dc4b9d56a08824eda /drivers/ide/ide-pm.c
parent	0893ed458b4b1d7c7667ca7ffb8b11febe7e7e6c (diff)

ext4: allow an active handle to be started when freezing

ext4_journal_start_sb() should not prevent an active handle from being started due to s_frozen. Otherwise, deadlock is easy to happen, below is a situation. ================================================ freeze | truncate ================================================ | ext4_ext_truncate() freeze_super() | starts a handle sets s_frozen | | ext4_ext_truncate() | holds i_data_sem ext4_freeze() | waits for updates | | ext4_free_blocks() | calls dquot_free_block() | | dquot_free_blocks() | calls ext4_dirty_inode() | | ext4_dirty_inode() | trys to start an active | handle | | block due to s_frozen ================================================ Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Reported-by: Amir Goldstein <amir73il@users.sf.net> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Andreas Dilger <adilger@dilger.ca>

Diffstat (limited to 'drivers/ide/ide-pm.c')

0 files changed, 0 insertions, 0 deletions

/* * acpi_utils.c - ACPI Utility Functions ($Revision: 10 $) * * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or (at * your option) any later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <linux/types.h> #include <acpi/acpi_bus.h> #include <acpi/acpi_drivers.h> #define _COMPONENT ACPI_BUS_COMPONENT ACPI_MODULE_NAME("utils"); /* -------------------------------------------------------------------------- Object Evaluation Helpers -------------------------------------------------------------------------- */ static void acpi_util_eval_error(acpi_handle h, acpi_string p, acpi_status s) { #ifdef ACPI_DEBUG_OUTPUT char prefix[80] = {'\0'}; struct acpi_buffer buffer = {sizeof(prefix), prefix}; acpi_get_name(h, ACPI_FULL_PATHNAME, &buffer); ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluate [%s.%s]: %s\n", (char *) prefix, p, acpi_format_exception(s))); #else return; #endif } acpi_status acpi_extract_package(union acpi_object *package, struct acpi_buffer *format, struct acpi_buffer *buffer) { u32 size_required = 0; u32 tail_offset = 0; char *format_string = NULL; u32 format_count = 0; u32 i = 0; u8 *head = NULL; u8 *tail = NULL; if (!package || (package->type != ACPI_TYPE_PACKAGE) || (package->package.count < 1)) { printk(KERN_WARNING PREFIX "Invalid package argument\n"); return AE_BAD_PARAMETER; } if (!format || !format->pointer || (format->length < 1)) { printk(KERN_WARNING PREFIX "Invalid format argument\n"); return AE_BAD_PARAMETER; } if (!buffer) { printk(KERN_WARNING PREFIX "Invalid buffer argument\n"); return AE_BAD_PARAMETER; } format_count = (format->length / sizeof(char)) - 1; if (format_count > package->package.count) { printk(KERN_WARNING PREFIX "Format specifies more objects [%d]" " than exist in package [%d].\n", format_count, package->package.count); return AE_BAD_DATA; } format_string = format->pointer; /* * Calculate size_required. */ for (i = 0; i < format_count; i++) { union acpi_object *element = &(package->package.elements[i]); if (!element) { return AE_BAD_DATA; } switch (element->type) { case ACPI_TYPE_INTEGER: switch (format_string[i]) { case 'N': size_required += sizeof(acpi_integer); tail_offset += sizeof(acpi_integer); break; case 'S': size_required += sizeof(char *) + sizeof(acpi_integer) + sizeof(char); tail_offset += sizeof(char *); break; default: printk(KERN_WARNING PREFIX "Invalid package element" " [%d]: got number, expecing" " [%c]\n", i, format_string[i]); return AE_BAD_DATA; break; } break; case ACPI_TYPE_STRING: case ACPI_TYPE_BUFFER: switch (format_string[i]) { case 'S': size_required += sizeof(char *) + (element->string.length * sizeof(char)) + sizeof(char); tail_offset += sizeof(char *); break; case 'B': size_required += sizeof(u8 *) + (element->buffer.length * sizeof(u8)); tail_offset += sizeof(u8 *); break; default: printk(KERN_WARNING PREFIX "Invalid package element" " [%d] got string/buffer," " expecing [%c]\n", i, format_string[i]); return AE_BAD_DATA; break; } break; case ACPI_TYPE_PACKAGE: default: ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unsupported element at index=%d\n", i)); /* TBD: handle nested packages... */ return AE_SUPPORT; break; } } /* * Validate output buffer. */ if (buffer->length < size_required) { buffer->length = size_required; return AE_BUFFER_OVERFLOW; } else if (buffer->length != size_required || !buffer->pointer) { return AE_BAD_PARAMETER; } head = buffer->pointer; tail = buffer->pointer + tail_offset; /* * Extract package data. */ for (i = 0; i < format_count; i++) { u8 **pointer = NULL; union acpi_object *element = &(package->package.elements[i]); if (!element) { return AE_BAD_DATA; } switch (element->type) { case ACPI_TYPE_INTEGER: switch (format_string[i]) { case 'N': *((acpi_integer *) head) = element->integer.value; head += sizeof(acpi_integer); break; case 'S': pointer = (u8 **) head; *pointer = tail; *((acpi_integer *) tail) = element->integer.value; head += sizeof(acpi_integer *); tail += sizeof(acpi_integer); /* NULL terminate string */ *tail = (char)0; tail += sizeof(char); break; default: /* Should never get here */ break; } break; case ACPI_TYPE_STRING: case ACPI_TYPE_BUFFER: switch (format_string[i]) { case 'S': pointer = (u8 **) head; *pointer = tail; memcpy(tail, element->string.pointer, element->string.length); head += sizeof(char *); tail += element->string.length * sizeof(char); /* NULL terminate string */ *tail = (char)0; tail += sizeof(char); break; case 'B': pointer = (u8 **) head; *pointer = tail; memcpy(tail, element->buffer.pointer, element->buffer.length); head += sizeof(u8 *); tail += element->buffer.length * sizeof(u8); break; default: /* Should never get here */ break; } break; case ACPI_TYPE_PACKAGE: /* TBD: handle nested packages... */ default: /* Should never get here */ break; } } return AE_OK; } EXPORT_SYMBOL(acpi_extract_package); acpi_status acpi_evaluate_integer(acpi_handle handle, acpi_string pathname, struct acpi_object_list *arguments, unsigned long long *data) { acpi_status status = AE_OK; union acpi_object element; struct acpi_buffer buffer = { 0, NULL }; if (!data) return AE_BAD_PARAMETER; buffer.length = sizeof(union acpi_object); buffer.pointer = &element; status = acpi_evaluate_object(handle, pathname, arguments, &buffer); if (ACPI_FAILURE(status)) { acpi_util_eval_error(handle, pathname, status); return status; } if (element.type != ACPI_TYPE_INTEGER) { acpi_util_eval_error(handle, pathname, AE_BAD_DATA); return AE_BAD_DATA; } *data = element.integer.value; ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%llu]\n", *data)); return AE_OK; } EXPORT_SYMBOL(acpi_evaluate_integer); #if 0 acpi_status acpi_evaluate_string(acpi_handle handle, acpi_string pathname, acpi_object_list * arguments, acpi_string * data) { acpi_status status = AE_OK; acpi_object *element = NULL; acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; if (!data) return AE_BAD_PARAMETER; status = acpi_evaluate_object(handle, pathname, arguments, &buffer); if (ACPI_FAILURE(status)) { acpi_util_eval_error(handle, pathname, status); return status; } element = (acpi_object *) buffer.pointer; if ((element->type != ACPI_TYPE_STRING) || (element->type != ACPI_TYPE_BUFFER) || !element->string.length) { acpi_util_eval_error(handle, pathname, AE_BAD_DATA); return AE_BAD_DATA; } *data = kzalloc(element->string.length + 1, GFP_KERNEL); if (!data) { printk(KERN_ERR PREFIX "Memory allocation\n"); return -ENOMEM; } memcpy(*data, element->string.pointer, element->string.length); ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%s]\n", *data)); kfree(buffer.pointer); return AE_OK; } #endif acpi_status acpi_evaluate_reference(acpi_handle handle, acpi_string pathname, struct acpi_object_list *arguments, struct acpi_handle_list *list) { acpi_status status = AE_OK; union acpi_object *package = NULL; union acpi_object *element = NULL; struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; u32 i = 0; if (!list) { return AE_BAD_PARAMETER; } /* Evaluate object. */ status = acpi_evaluate_object(handle, pathname, arguments, &buffer); if (ACPI_FAILURE(status)) goto end; package = buffer.pointer; if ((buffer.length == 0) || !package) { printk(KERN_ERR PREFIX "No return object (len %X ptr %p)\n", (unsigned)buffer.length, package); status = AE_BAD_DATA; acpi_util_eval_error(handle, pathname, status); goto end; } if (package->type != ACPI_TYPE_PACKAGE) { printk(KERN_ERR PREFIX "Expecting a [Package], found type %X\n", package->type); status = AE_BAD_DATA; acpi_util_eval_error(handle, pathname, status); goto end; } if (!package->package.count) { printk(KERN_ERR PREFIX "[Package] has zero elements (%p)\n", package); status = AE_BAD_DATA; acpi_util_eval_error(handle, pathname, status); goto end; } if (package->package.count > ACPI_MAX_HANDLES) { return AE_NO_MEMORY; } list->count = package->package.count; /* Extract package data. */ for (i = 0; i < list->count; i++) {


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