From: Gabor Juhos 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 Signed-off-by: Felix Fietkau --- drivers/spi/spi-fsl-espi.c | 34 ++++++++++++++++------------------ drivers/spi/spi-fsl-lib.h | 1 + 2 files changed, 17 insertions(+), 18 deletions(-) --- a/drivers/spi/spi-fsl-espi.c +++ b/drivers/spi/spi-fsl-espi.c @@ -332,17 +332,13 @@ static void fsl_espi_do_trans(struct spi 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); @@ -355,16 +351,17 @@ static void fsl_espi_cmd_trans(struct sp 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 total_len = espi_trans->len; 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; @@ -373,12 +370,6 @@ static void fsl_espi_rw_trans(struct spi unsigned int pos; int i, loop; - local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL); - if (!local_buf) { - espi_trans->status = -ENOMEM; - return; - } - for (pos = 0, loop = 0; pos < total_len; pos += trans_len, loop++) { trans_len = total_len - pos; @@ -424,8 +415,6 @@ static void fsl_espi_rw_trans(struct spi else espi_trans->actual_length += espi_trans->len; } - - kfree(local_buf); } static int fsl_espi_do_one_msg(struct spi_master *master, @@ -673,6 +662,12 @@ static struct spi_master * fsl_espi_prob mpc8xxx_spi = spi_master_get_devdata(master); + mpc8xxx_spi->local_buf = devm_kzalloc(dev, SPCOM_TRANLEN_MAX, GFP_KERNEL); + if (!mpc8xxx_spi->local_buf) { + ret = -ENOMEM; + goto err_probe; + } + mpc8xxx_spi->reg_base = devm_ioremap_resource(dev, mem); if (IS_ERR(mpc8xxx_spi->reg_base)) { ret = PTR_ERR(mpc8xxx_spi->reg_base); --- a/drivers/spi/spi-fsl-lib.h +++ b/drivers/spi/spi-fsl-lib.h @@ -30,6 +30,7 @@ struct mpc8xxx_spi { void *rx; #if IS_ENABLED(CONFIG_SPI_FSL_ESPI) int len; + u8 *local_buf; #endif int subblock;