--- /dev/null
+From: Gabor Juhos <juhosg@openwrt.org>
+Subject: spi-fsl-espi: avoid frequent high order allocations
+
+The driver allocates 64KiB of memory fro a local buffer before
+each transfer and releases that afterwards. When the memory is
+fragmented this allocation often fails and causes a warning like
+this:
+
+ kworker/u2:2: page allocation failure: order:4, mode:0x10c0d0
+ CPU: 0 PID: 7011 Comm: kworker/u2:2 Not tainted 3.10.24 #1
+ Workqueue: ffe07000.spi mpc8xxx_spi_work
+ Call Trace:
+ [c1c6dcf0] [c0006914] show_stack+0x50/0x170 (unreliable)
+ [c1c6dd30] [c0259858] dump_stack+0x24/0x34
+ [c1c6dd40] [c00672e8] warn_alloc_failed+0x120/0x13c
+ [c1c6dd90] [c0069920] __alloc_pages_nodemask+0x574/0x5c8
+ [c1c6de20] [c0069990] __get_free_pages+0x1c/0x4c
+ [c1c6de30] [c0185174] fsl_espi_do_one_msg+0x128/0x2a0
+ [c1c6de90] [c0184290] mpc8xxx_spi_work+0x50/0x7c
+ [c1c6dea0] [c0037af8] process_one_work+0x208/0x30c
+ [c1c6dec0] [c00387a0] worker_thread+0x20c/0x308
+ [c1c6def0] [c003de60] kthread+0xa4/0xa8
+ [c1c6df40] [c000c4bc] ret_from_kernel_thread+0x5c/0x64
+
+ m25p80 spi0.0: error -12 reading SR
+ end_request: I/O error, dev mtdblock3, sector 680
+ SQUASHFS error: squashfs_read_data failed to read block 0x54a4a
+ SQUASHFS error: Unable to read data cache entry [54a4a]
+
+Preallocate the buffer from the probe routine to avoid
+this.
+
+Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
+---
+ drivers/spi/spi-fsl-espi.c | 34 ++++++++++++++++------------------
+ drivers/spi/spi-fsl-lib.h | 1 +
+ 2 files changed, 17 insertions(+), 18 deletions(-)
+
+diff --git a/drivers/spi/spi-fsl-espi.c b/drivers/spi/spi-fsl-espi.c
+index d0a73a0..f461dde 100644
+--- a/drivers/spi/spi-fsl-espi.c
++++ b/drivers/spi/spi-fsl-espi.c
+@@ -329,17 +329,13 @@ static void fsl_espi_do_trans(struct spi_message *m,
+ static void fsl_espi_cmd_trans(struct spi_message *m,
+ struct fsl_espi_transfer *trans, u8 *rx_buff)
+ {
++ struct spi_device *spi = m->spi;
++ struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
+ struct spi_transfer *t;
+- u8 *local_buf;
++ u8 *local_buf = mspi->local_buf;
+ int i = 0;
+ struct fsl_espi_transfer *espi_trans = trans;
+
+- local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
+- if (!local_buf) {
+- espi_trans->status = -ENOMEM;
+- return;
+- }
+-
+ list_for_each_entry(t, &m->transfers, transfer_list) {
+ if (t->tx_buf) {
+ memcpy(local_buf + i, t->tx_buf, t->len);
+@@ -352,28 +348,23 @@ static void fsl_espi_cmd_trans(struct spi_message *m,
+ fsl_espi_do_trans(m, espi_trans);
+
+ espi_trans->actual_length = espi_trans->len;
+- kfree(local_buf);
+ }
+
+ static void fsl_espi_rw_trans(struct spi_message *m,
+ struct fsl_espi_transfer *trans, u8 *rx_buff)
+ {
++ struct spi_device *spi = m->spi;
++ struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
+ struct fsl_espi_transfer *espi_trans = trans;
+ unsigned int n_tx = espi_trans->n_tx;
+ unsigned int n_rx = espi_trans->n_rx;
+ struct spi_transfer *t;
+- u8 *local_buf;
++ u8 *local_buf = mspi->local_buf;
+ u8 *rx_buf = rx_buff;
+ unsigned int trans_len;
+ unsigned int addr;
+ int i, pos, loop;
+
+- local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
+- if (!local_buf) {
+- espi_trans->status = -ENOMEM;
+- return;
+- }
+-
+ for (pos = 0, loop = 0; pos < n_rx; pos += trans_len, loop++) {
+ trans_len = n_rx - pos;
+ if (trans_len > SPCOM_TRANLEN_MAX - n_tx)
+@@ -407,8 +398,6 @@ static void fsl_espi_rw_trans(struct spi_message *m,
+ else
+ espi_trans->actual_length += espi_trans->len;
+ }
+-
+- kfree(local_buf);
+ }
+
+ static int fsl_espi_do_one_msg(struct spi_master *master,
+@@ -586,6 +575,7 @@ static irqreturn_t fsl_espi_irq(s32 irq, void *context_data)
+ static void fsl_espi_remove(struct mpc8xxx_spi *mspi)
+ {
+ iounmap(mspi->reg_base);
++ kfree(mspi->local_buf);
+ }
+
+ static int fsl_espi_suspend(struct spi_master *master)
+@@ -652,10 +642,16 @@ static struct spi_master * fsl_espi_probe(struct device *dev,
+ mpc8xxx_spi = spi_master_get_devdata(master);
+ mpc8xxx_spi->spi_remove = fsl_espi_remove;
+
++ mpc8xxx_spi->local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
++ if (!mpc8xxx_spi->local_buf) {
++ ret = -ENOMEM;
++ goto err_probe;
++ }
++
+ mpc8xxx_spi->reg_base = ioremap(mem->start, resource_size(mem));
+ if (!mpc8xxx_spi->reg_base) {
+ ret = -ENOMEM;
+- goto err_probe;
++ goto free_buf;
+ }
+
+ reg_base = mpc8xxx_spi->reg_base;
+@@ -722,6 +718,8 @@ unreg_master:
+ free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
+ free_irq:
+ iounmap(mpc8xxx_spi->reg_base);
++free_buf:
++ kfree(mpc8xxx_spi->local_buf);
+ err_probe:
+ spi_master_put(master);
+ err:
+diff --git a/drivers/spi/spi-fsl-lib.h b/drivers/spi/spi-fsl-lib.h
+index b4ed04e..3ffa984 100644
+--- a/drivers/spi/spi-fsl-lib.h
++++ b/drivers/spi/spi-fsl-lib.h
+@@ -30,6 +30,7 @@ struct mpc8xxx_spi {
+ void *rx;
+ #ifdef CONFIG_SPI_FSL_ESPI
+ int len;
++ u8 *local_buf;
+ #endif
+
+ int subblock;
+--
+2.3.0
+
projects / 15.05 / openwrt.git / blobdiff