Upstream-Status: Backport Signed-off-by: Kai Kang From 0e7ef22136955169a0fd03c4e41af95662352733 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Tue, 2 Jun 2015 15:07:01 +0000 Subject: xen/pt: split out calculation of throughable mask in PCI config space handling Bug-Debian: http://bugs.debian.org/787547 This is just to avoid having to adjust that calculation later in multiple places. Note that including ->ro_mask in get_throughable_mask()'s calculation is only an apparent (i.e. benign) behavioral change: For r/o fields it doesn't matter > whether they get passed through - either the same flag is also set in emu_mask (then there's no change at all) or the field is r/o in hardware (and hence a write won't change it anyway). This is a preparatory patch for XSA-131. Signed-off-by: Jan Beulich Acked-by: Stefano Stabellini Reviewed-by: Anthony PERARD --- hw/xen/xen_pt_config_init.c | 51 ++++++++++++++++++--------------------------- 1 file changed, 20 insertions(+), 31 deletions(-) Index: qemu-2.2.0/hw/xen/xen_pt_config_init.c =================================================================== --- qemu-2.2.0.orig/hw/xen/xen_pt_config_init.c +++ qemu-2.2.0/hw/xen/xen_pt_config_init.c @@ -95,6 +95,14 @@ XenPTReg *xen_pt_find_reg(XenPTRegGroup return NULL; } +static uint32_t get_throughable_mask(const XenPCIPassthroughState *s, + const XenPTRegInfo *reg, + uint32_t valid_mask) +{ + uint32_t throughable_mask = ~(reg->emu_mask | reg->ro_mask); + + return throughable_mask & valid_mask; +} /**************** * general register functions @@ -157,14 +165,13 @@ static int xen_pt_byte_reg_write(XenPCIP { XenPTRegInfo *reg = cfg_entry->reg; uint8_t writable_mask = 0; - uint8_t throughable_mask = 0; + uint8_t throughable_mask = get_throughable_mask(s, reg, valid_mask); /* modify emulate register */ writable_mask = reg->emu_mask & ~reg->ro_mask & valid_mask; cfg_entry->data = XEN_PT_MERGE_VALUE(*val, cfg_entry->data, writable_mask); /* create value for writing to I/O device register */ - throughable_mask = ~reg->emu_mask & valid_mask; *val = XEN_PT_MERGE_VALUE(*val, dev_value, throughable_mask); return 0; @@ -175,14 +182,13 @@ static int xen_pt_word_reg_write(XenPCIP { XenPTRegInfo *reg = cfg_entry->reg; uint16_t writable_mask = 0; - uint16_t throughable_mask = 0; + uint16_t throughable_mask = get_throughable_mask(s, reg, valid_mask); /* modify emulate register */ writable_mask = reg->emu_mask & ~reg->ro_mask & valid_mask; cfg_entry->data = XEN_PT_MERGE_VALUE(*val, cfg_entry->data, writable_mask); /* create value for writing to I/O device register */ - throughable_mask = ~reg->emu_mask & valid_mask; *val = XEN_PT_MERGE_VALUE(*val, dev_value, throughable_mask); return 0; @@ -193,14 +199,13 @@ static int xen_pt_long_reg_write(XenPCIP { XenPTRegInfo *reg = cfg_entry->reg; uint32_t writable_mask = 0; - uint32_t throughable_mask = 0; + uint32_t throughable_mask = get_throughable_mask(s, reg, valid_mask); /* modify emulate register */ writable_mask = reg->emu_mask & ~reg->ro_mask & valid_mask; cfg_entry->data = XEN_PT_MERGE_VALUE(*val, cfg_entry->data, writable_mask); /* create value for writing to I/O device register */ - throughable_mask = ~reg->emu_mask & valid_mask; *val = XEN_PT_MERGE_VALUE(*val, dev_value, throughable_mask); return 0; @@ -309,7 +314,7 @@ static int xen_pt_cmd_reg_write(XenPCIPa { XenPTRegInfo *reg = cfg_entry->reg; uint16_t writable_mask = 0; - uint16_t throughable_mask = 0; + uint16_t throughable_mask = get_throughable_mask(s, reg, valid_mask); uint16_t emu_mask = reg->emu_mask; if (s->is_virtfn) { @@ -321,8 +326,6 @@ static int xen_pt_cmd_reg_write(XenPCIPa cfg_entry->data = XEN_PT_MERGE_VALUE(*val, cfg_entry->data, writable_mask); /* create value for writing to I/O device register */ - throughable_mask = ~emu_mask & valid_mask; - if (*val & PCI_COMMAND_INTX_DISABLE) { throughable_mask |= PCI_COMMAND_INTX_DISABLE; } else { @@ -478,7 +481,6 @@ static int xen_pt_bar_reg_write(XenPCIPa PCIDevice *d = &s->dev; const PCIIORegion *r; uint32_t writable_mask = 0; - uint32_t throughable_mask = 0; uint32_t bar_emu_mask = 0; uint32_t bar_ro_mask = 0; uint32_t r_size = 0; @@ -535,8 +537,7 @@ static int xen_pt_bar_reg_write(XenPCIPa } /* create value for writing to I/O device register */ - throughable_mask = ~bar_emu_mask & valid_mask; - *val = XEN_PT_MERGE_VALUE(*val, dev_value, throughable_mask); + *val = XEN_PT_MERGE_VALUE(*val, dev_value, 0); return 0; } @@ -550,9 +551,8 @@ static int xen_pt_exp_rom_bar_reg_write( XenPTRegion *base = NULL; PCIDevice *d = (PCIDevice *)&s->dev; uint32_t writable_mask = 0; - uint32_t throughable_mask = 0; + uint32_t throughable_mask = get_throughable_mask(s, reg, valid_mask); pcibus_t r_size = 0; - uint32_t bar_emu_mask = 0; uint32_t bar_ro_mask = 0; r_size = d->io_regions[PCI_ROM_SLOT].size; @@ -561,7 +561,6 @@ static int xen_pt_exp_rom_bar_reg_write( r_size = xen_pt_get_emul_size(base->bar_flag, r_size); /* set emulate mask and read-only mask */ - bar_emu_mask = reg->emu_mask; bar_ro_mask = (reg->ro_mask | (r_size - 1)) & ~PCI_ROM_ADDRESS_ENABLE; /* modify emulate register */ @@ -569,7 +568,6 @@ static int xen_pt_exp_rom_bar_reg_write( cfg_entry->data = XEN_PT_MERGE_VALUE(*val, cfg_entry->data, writable_mask); /* create value for writing to I/O device register */ - throughable_mask = ~bar_emu_mask & valid_mask; *val = XEN_PT_MERGE_VALUE(*val, dev_value, throughable_mask); return 0; @@ -964,14 +962,13 @@ static int xen_pt_pmcsr_reg_write(XenPCI { XenPTRegInfo *reg = cfg_entry->reg; uint16_t writable_mask = 0; - uint16_t throughable_mask = 0; + uint16_t throughable_mask = get_throughable_mask(s, reg, valid_mask); /* modify emulate register */ writable_mask = reg->emu_mask & ~reg->ro_mask & valid_mask; cfg_entry->data = XEN_PT_MERGE_VALUE(*val, cfg_entry->data, writable_mask); /* create value for writing to I/O device register */ - throughable_mask = ~reg->emu_mask & valid_mask; *val = XEN_PT_MERGE_VALUE(*val, dev_value & ~PCI_PM_CTRL_PME_STATUS, throughable_mask); @@ -1060,7 +1057,7 @@ static int xen_pt_msgctrl_reg_write(XenP XenPTRegInfo *reg = cfg_entry->reg; XenPTMSI *msi = s->msi; uint16_t writable_mask = 0; - uint16_t throughable_mask = 0; + uint16_t throughable_mask = get_throughable_mask(s, reg, valid_mask); /* Currently no support for multi-vector */ if (*val & PCI_MSI_FLAGS_QSIZE) { @@ -1073,7 +1070,6 @@ static int xen_pt_msgctrl_reg_write(XenP msi->flags |= cfg_entry->data & ~PCI_MSI_FLAGS_ENABLE; /* create value for writing to I/O device register */ - throughable_mask = ~reg->emu_mask & valid_mask; *val = XEN_PT_MERGE_VALUE(*val, dev_value, throughable_mask); /* update MSI */ @@ -1185,7 +1181,6 @@ static int xen_pt_msgaddr32_reg_write(Xe { XenPTRegInfo *reg = cfg_entry->reg; uint32_t writable_mask = 0; - uint32_t throughable_mask = 0; uint32_t old_addr = cfg_entry->data; /* modify emulate register */ @@ -1194,8 +1189,7 @@ static int xen_pt_msgaddr32_reg_write(Xe s->msi->addr_lo = cfg_entry->data; /* create value for writing to I/O device register */ - throughable_mask = ~reg->emu_mask & valid_mask; - *val = XEN_PT_MERGE_VALUE(*val, dev_value, throughable_mask); + *val = XEN_PT_MERGE_VALUE(*val, dev_value, 0); /* update MSI */ if (cfg_entry->data != old_addr) { @@ -1213,7 +1207,6 @@ static int xen_pt_msgaddr64_reg_write(Xe { XenPTRegInfo *reg = cfg_entry->reg; uint32_t writable_mask = 0; - uint32_t throughable_mask = 0; uint32_t old_addr = cfg_entry->data; /* check whether the type is 64 bit or not */ @@ -1230,8 +1223,7 @@ static int xen_pt_msgaddr64_reg_write(Xe s->msi->addr_hi = cfg_entry->data; /* create value for writing to I/O device register */ - throughable_mask = ~reg->emu_mask & valid_mask; - *val = XEN_PT_MERGE_VALUE(*val, dev_value, throughable_mask); + *val = XEN_PT_MERGE_VALUE(*val, dev_value, 0); /* update MSI */ if (cfg_entry->data != old_addr) { @@ -1253,7 +1245,6 @@ static int xen_pt_msgdata_reg_write(XenP XenPTRegInfo *reg = cfg_entry->reg; XenPTMSI *msi = s->msi; uint16_t writable_mask = 0; - uint16_t throughable_mask = 0; uint16_t old_data = cfg_entry->data; uint32_t offset = reg->offset; @@ -1271,8 +1262,7 @@ static int xen_pt_msgdata_reg_write(XenP msi->data = cfg_entry->data; /* create value for writing to I/O device register */ - throughable_mask = ~reg->emu_mask & valid_mask; - *val = XEN_PT_MERGE_VALUE(*val, dev_value, throughable_mask); + *val = XEN_PT_MERGE_VALUE(*val, dev_value, 0); /* update MSI */ if (cfg_entry->data != old_data) { @@ -1434,7 +1424,7 @@ static int xen_pt_msixctrl_reg_write(Xen { XenPTRegInfo *reg = cfg_entry->reg; uint16_t writable_mask = 0; - uint16_t throughable_mask = 0; + uint16_t throughable_mask = get_throughable_mask(s, reg, valid_mask); int debug_msix_enabled_old; /* modify emulate register */ @@ -1442,7 +1432,6 @@ static int xen_pt_msixctrl_reg_write(Xen cfg_entry->data = XEN_PT_MERGE_VALUE(*val, cfg_entry->data, writable_mask); /* create value for writing to I/O device register */ - throughable_mask = ~reg->emu_mask & valid_mask; *val = XEN_PT_MERGE_VALUE(*val, dev_value, throughable_mask); /* update MSI-X */